Publications by authors named "Suresh K Bhargava"

131 Publications

Triazolyl-Functionalized N-Heterocyclic Carbene Half-Sandwich Compounds: Coordination Mode, Reactivity and in vitro Anticancer Activity.

ChemMedChem 2021 Jul 1. Epub 2021 Jul 1.

School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand.

We report investigations on the anticancer activity of organometallic [M (η -p-cymene/η -pentamethylcyclopentadienyl)] (M=Ru, Os, Rh, and Ir) complexes of N-heterocyclic carbenes (NHCs) substituted with a triazolyl moiety. Depending on the precursors, the NHC ligands displayed either mono- or bidentate coordination via the NHC carbon atom or as N,C-donors. The metal complexes were investigated for their stability in aqueous solution, with the interpretation supported by density functional theory calculations, and reactivity to biomolecules. In vitro cytotoxicity studies suggested that the nature of both the metal center and the lipophilicity of the ligand determine the biological properties of this class of compounds. The Ir complex 5 d bearing a benzimidazole-derived ligand was the most cytotoxic with an IC value of 10 μM against NCI-H460 non-small cell lung carcinoma cells. Cell uptake and distribution studies using X-ray fluorescence microscopy revealed localization of 5 d in the cytoplasm of cancer cells.
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http://dx.doi.org/10.1002/cmdc.202100311DOI Listing
July 2021

Liquid Crystal-Mediated 3D Printing Process to Fabricate Nano-Ordered Layered Structures.

ACS Appl Mater Interfaces 2021 Jun 10;13(24):28627-28638. Epub 2021 Jun 10.

School of Chemical Engineering, University of New South Wales (UNSW), Sydney 2052, New South Wales, Australia.

The emergence of three-dimensional (3D) printing promises a disruption in the design and on-demand fabrication of smart structures in applications ranging from functional devices to human organs. However, the scale at which 3D printing excels is within macro- and microlevels and principally lacks the spatial ordering of building blocks at nanolevels, which is vital for most multifunctional devices. Herein, we employ liquid crystal (LC) inks to bridge the gap between the nano- and microscales in a single-step 3D printing. The LC ink is prepared from mixtures of LCs of nanocellulose whiskers and large sheets of graphene oxide, which offers a highly ordered laminar organization not inherently present in the source materials. LC-mediated 3D printing imparts the fine-tuning required for the design freedom of architecturally layered systems at the nanoscale with intricate patterns within the 3D-printed constructs. This approach empowered the development of a high-performance humidity sensor composed of self-assembled lamellar organization of NC whiskers. We observed that the NC whiskers that are flat and parallel to each other in the laminar organization allow facile mass transport through the structure, demonstrating a significant improvement in the sensor performance. This work exemplifies how LC ink, implemented in a 3D printing process, can unlock the potential of individual constituents to allow macroscopic printing architectures with nanoscopic arrangements.
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http://dx.doi.org/10.1021/acsami.1c05025DOI Listing
June 2021

Cinnamide derived pyrimidine-benzimidazole hybrids as tubulin inhibitors: Synthesis, in silico and cell growth inhibition studies.

Bioorg Chem 2021 May 24;110:104765. Epub 2021 Feb 24.

Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad 500 037, India. Electronic address:

An approach in modern medicinal chemistry to discover novel bioactive compounds is by mimicking diverse complementary pharmacophores. In extension of this strategy, a new class of piperazine-linked cinnamide derivatives of benzimidazole-pyrimidine hybrids have been designed and synthesized. Their in vitro cytotoxicity profiles were explored on selected human cancer cell lines. Specifically, structural comparison of target hybrids with tubulin-DAMA-colchicine and tubulin-nocodazole complexes has exposed a deep position of benzimidazole ring into the αT5 loop. All the synthesized compounds were demonstrated modest to interesting cytotoxicity against different cancer cell lines. The utmost cytotoxicity has shown with an amine linker of benzimidazole-pyrimidine series, with specificity toward A549 (lung cancer) cell line. The most potent compound in this series was 18i, which inhibited cancer cell growth at micromolar concentrations ranging 2.21-7.29 µM. Flow cytometry studies disclosed that 18i inhibited the cells in G2/M phase of cell cycle. The potent antitumor activity of 18i resulted from enhanced microtubule disruption at a similar level as nocodazole on β-tubulin antibody, explored using immunofluorescence staining. The most active compound 18i also inhibited tubulin polymerization with an IC of 5.72 ± 0.51 µM. In vitro biological analysis of 18i presented apoptosis induction on A549 cells with triggering of ROS generation and loss of mitochondrial membrane potential, resulting in DNA injury. In addition, 18i displayed impairment in cellular migration and inhibited the colony formation. Notably, the safety profile of most potent compound 18i was revealed by screening against normal human pulmonary epithelial cells (L132: IC: 69.25 ± 5.95 μM). The detailed binding interactions of 18i with tubulin was investigated by employing molecular docking, superimposition and free energy analyses. Thus remarks made in this study established that pyrimidine-benzimidazole hybrids as a new class of tubulin polymerization inhibitors with significant anticancer activity.
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http://dx.doi.org/10.1016/j.bioorg.2021.104765DOI Listing
May 2021

Oxidative dehydrogenation of ethane: catalytic and mechanistic aspects and future trends.

Chem Soc Rev 2021 Apr 17;50(7):4564-4605. Epub 2021 Feb 17.

Department of Energy Engineering, Budapest University of Technology and Economics, Budapest, Hungary.

Ethene is a commodity chemical of great importance for manufacturing diverse consumer products, whose synthesis via crude oil steam cracking is one of the most energy-intensive processes in the petrochemical industry. Oxidative dehydrogenation (ODH) of ethane is an attractive, low energy, alternative route to ethene which could reduce the carbon footprint for its production, however, the commercial implementation of ODH requires catalysts with improved selectivity. This review critically assesses recent developments in catalytic technologies for ethane ODH, and discusses how insight into proposed mechanisms from computational studies, and CO assisted ethane dehydrogenation (CO-DHE), provide opportunities for economically viable processes to meet growing demands for ethene while reducing carbon emissions. Future trends and emerging technologies for ethane ODH are also discussed.
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http://dx.doi.org/10.1039/d0cs01518kDOI Listing
April 2021

Performance of chemically resistant polyurea reverse osmosis membrane in the treatment of highly alkaline industrial wastewater containing sodium aluminate.

Water Sci Technol 2020 Dec;82(11):2259-2270

Membrane Separations Laboratory, PETT Department, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India E-mail:

The goal of the present study is to treat industrial wastewater containing sodium aluminate using a chemically inert polyurea (PU) based thin film composite (TFC) reverse osmosis (RO) membrane to promote water reclamation and zero liquid discharge (ZLD). Pretreatment was carried out to reduce the pH of the effluent from 12.5 to 7.1. The TFC RO membrane was fabricated by coating PU on Polyethersulfone (PES) substrate by interfacial polymerization (IP). The surface and cross-sectional morphologies of the membrane were characterized using scanning electron microscopy (SEM). The indigenously synthesized membrane was effective in the removal of total dissolved solids (TDS), chemical oxygen demand (COD), colour and electrical conductivity. The experiments were conducted by varying the feed composition of the wastewater. The maximum water recovery and flux were found to be 74% and 73.9 L/mh. RO process using PU membrane exhibited significant potential for cost effective, safe and pollution-free treatment of sodium aluminate industrial effluent.
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http://dx.doi.org/10.2166/wst.2020.495DOI Listing
December 2020

Low-Temperature Hydrogen Sensor: Enhanced Performance Enabled through Photoactive Pd-Decorated TiO Colloidal Crystals.

ACS Sens 2020 12 1;5(12):3902-3914. Epub 2020 Dec 1.

Centre for Advanced Materials and Industrial Chemistry (CAMIC), School of Science, RMIT University, Melbourne 3001, Victoria, Australia.

The high demand for H gas sensors is not just limited to industrial process control and leak detection applications but also extends to the food and medical industry to determine the presence of various types of bacteria or underlying medical conditions. For instance, sensing of H at low concentrations (<10 ppm) is essential for developing breath analyzers for the noninvasive diagnosis of some gastrointestinal diseases. However, there are major challenges to overcome in order to achieve high sensitivity and hence low limit of detection (LoD) toward H. In this study, it is demonstrated that light-assisted amperometric gas sensors employing sensitive layers based on Pd-decorated TiO long-range ordered crystals can achieve excellent H sensing performance. This unique combination of materials and novel layered structure enables the detection of H gas down to 50 ppm with highly promising LoD capabilities. The sensor response profiles revealed that the sensor's signal-to-noise ratio was higher in the presence of light when operated with a 9 V bias (relative to other conditions used), producing a LoD of only 3.5 ppm at an operating temperature of 33 °C. The high performance of the sensor makes it attractive for applications that require low-level (ppm as opposed to conventional % levels) H gas detection. Most importantly, the developed sensor exhibited high selectivity (>93%) toward H over other gas species such as CO, CHO, CHO, CHCHO, and NO, which are commonly found to coexist in the environment.
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http://dx.doi.org/10.1021/acssensors.0c01387DOI Listing
December 2020

Self-assembled nanostructures of phosphomolybdate, nucleobase and metal ions synthesis and their cytotoxicity studies on cancer cell lines.

J Mater Chem B 2020 12;8(48):11044-11054

Centre for Advanced Materials and Industrial Chemistry, School of Science, RMIT University, Melbourne, Australia.

The ability of the multidentate nucleobases, adenine and thymine, to coordinate polyoxometalate and metal ions leading to the formation of self-assembled nanostructures and their strong cytotoxicity toward cancer cell lines have been demonstrated. A unique synthetic approach is developed to make a series of functional nanoscale hybrid materials consisting of nucleobases (adenine and thymine) and phosphomolybdic acid (PMA) through solid state chemical reaction and self-assembly process. Adenine was protonated through its ring nitrogen, while the ketone group in thymine was protonated during the addition of PMA to these nucleobases. The self-assembled nanostructures formed as a result of the electrostatic interaction between the protonated nucleobases and polyanionic PMA. To promote the base pairing between the nucleobases, chloroaurate ions and silver ions were added to each PMA/adenine and PMA/thymine nanostructures. The complexation between the nucleobases and the added metal ions was found to drive the formation of subsequent self-assembled nanostructures. All the materials were screened for their anticancer activity against breast (MDAMB-231) and prostate (PC-3) cancer cells, and non-cancerous keratinocyte cells HaCaT. PMA/adenine/[AuCl4]- and PMA/thymine/Ag+ nanostructures were found to have strong anti-cancer activity, while PMA/adenine/Ag+, PMA/thymine/[AuCl4]-, and PMA/pdenine, PMA/thymine nanostructures did not exhibit such activity. The unique redox properties of these materials and the self-assembly of the PMA and metal ions were the major factors responsible for the cytotoxicity. This unique approach of making functional nanomaterials incorporate the nucleobase, PMA and metal ions using solid state self-assembly and their anti-cancer applications are considered to be an effective approach for the development of inorganic nucleoside analogue bio-pharmaceutical agents.
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http://dx.doi.org/10.1039/d0tb01945cDOI Listing
December 2020

Mercury-bearing wastes: Sources, policies and treatment technologies for mercury recovery and safe disposal.

J Environ Manage 2020 Sep 14;270:110945. Epub 2020 Jun 14.

Centre for Advanced Materials & Industrial Chemistry (CAMIC), School of Science, RMIT University, GPO Box 2476, Melbourne, VIC 3001, Australia. Electronic address:

Due to the lenient environmental policies in developing economies, mercury-containing wastes are partly produced as a result of the employment of mercury in manufacturing and consumer products. Worldwide, the presence of mercury as an impurity in several industrial processes leads to significant amounts of contaminated waste. The Minamata Convention on Mercury dictates that mercury-containing wastes should be handled in an environmentally sound way according to the Basel Convention Technical Guidelines. Nevertheless, the management policies differ a great deal from one country to another because only a few deploy or can afford to deploy the required technology and facilities. In general, elemental mercury and mercury-bearing wastes should be stabilized and solidified before they are disposed of or permanently stored in specially engineered landfills and facilities, respectively. Prior to physicochemical treatment and depending on mercury's concentration, the contaminated waste may be thermally or chemically processed to reduce mercury's content to an acceptable level. The suitability of the treated waste for final disposal is then assessed by the application of standard leaching tests whose capacity to evaluate its long-term behavior is rather questionable. This review critically discusses the main methods employed for the recovery of mercury and the treatment of contaminated waste by analyzing representative examples from the industry. Furthermore, it gives a complete overview of all relevant issues by presenting the sources of mercury-bearing wastes, explaining the problems associated with the operation of conventional discharging facilities and providing an insight of the disposal policies adopted in selected geographical regions.
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http://dx.doi.org/10.1016/j.jenvman.2020.110945DOI Listing
September 2020

Innovative Molecular Design Strategies in Materials Science Following the Aurophilicity Concept.

Chem Rev 2020 08 14;120(15):7551-7591. Epub 2020 Jul 14.

Centre for Advanced Materials and Industrial Chemistry (CAMIC), School of Science, RMIT University, GPO BOX 2476, Melbourne 3001, Australia.

The past decade has seen a diverse range of breakthrough inventions that are derived from gold complexes, including the application of aurophilic interactions in the preparation of stimuli-responsive materials. Examples of these gold-based materials include aurophilicity-induced metallogelators, mechanochromic, thermochromic, vapochromic, and solvatochromic luminescent compounds, as well as sensory materials for the detection of metal ions. Sophisticated properties of gold complexes with Au···Au contacts have been explored at the edge of several disciplines including chemistry, crystallography, molecular engineering and advanced materials. As science paves its way to innovation, cross-disciplinary research moves from being a luxury to becoming a necessity. Development of the concept of aurophilicity and its use in designing novel materials is a true example of innovation on a multidisciplinary platform. As miniaturization continues to influence the next generation of technological advancement, using the properties of molecules as chemical tools to enable such developments becomes extremely important. In this Review, recent examples of gold complexes which exhibit a response to external stimuli have been collected and some of their potential applications discussed for selected cases.
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http://dx.doi.org/10.1021/acs.chemrev.9b00816DOI Listing
August 2020

Exploration of carbamide derived pyrimidine-thioindole conjugates as potential VEGFR-2 inhibitors with anti-angiogenesis effect.

Eur J Med Chem 2020 Aug 12;200:112457. Epub 2020 May 12.

Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, 500 037, India. Electronic address:

The development of new small molecules from known structural motifs through molecular hybridization is one of the trends in drug discovery. In this connection, we have combined the two pharmacophoric units (pyrimidine and thioindole) in a single entity via molecular hybridization strategy along with introduction of urea functionality at C2 position of pyrimidine to increase the efficiency of H-bonding interactions. Among the synthesized conjugates 12a-aa, compound 12k was found to exhibit significant IC values 5.85, 7.87, 6.41 and 10.43 μM against MDA-MB-231 (breast), HepG2 (liver), A549 (lung) and PC-3 (prostate) cancer cell lines, respectively. All these compounds were further evaluated for their inhibitory activities against VEGFR-2 protein. The results specified that among the tested compounds, 12d, 12e, 12k, 12l, 12p, 12q, 12t and 12u prominently suppressed VEGFR-2, with IC values of 310-920 nM in association to the positive control (210 nM). Angiogenesis inhibition was evident by tube formation assay in HUVECs and cell-invasion by transwell assay. The mechanism of cellular toxicity on MDA-MB-231 was found through depolarisation of mitochondrial membrane potential, increased ROS production and subsequent DNA damage resulting in apoptosis induction. Moreover, clonogenic and wound healing assays designated the inhibition of colony formation and cell migration by 12k in a dose-dependent manner. Molecular docking studies also shown that compound 12k capably intermingled with catalytically active residues GLU-885, ASP-1046 of the VEGFR-2 through hydrogen-bonding interactions.
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http://dx.doi.org/10.1016/j.ejmech.2020.112457DOI Listing
August 2020

Antitumor and Antiangiogenic Properties of Gold(III) Complexes Containing Cycloaurated Triphenylphosphine Sulfide Ligands.

Inorg Chem 2020 Apr 7;59(8):5662-5673. Epub 2020 Apr 7.

Centre for Advanced Materials and Industrial Chemistry, School of Science, RMIT University, G.P.O. Box 2476, Melbourne 3001, Australia.

A family of stable anticancer gold(III)-based therapeutic complexes containing cyclometalated triphenylphosphine sulfide ligands have been prepared. The anticancer properties of the newly developed complexes [AuCl{κ-2-CHP(S)Ph}] (), [Au(κ-SCNEt){κ-2-CHP(S)Ph}]PF (), [AuCl(dppe){κ-2-CHP(S)Ph}]Cl (), and [Au(dppe){κ-2-CHP(S)Ph}][PF] () were investigated toward five human cancer cell lines [cervical (HeLa), lung (A549), prostate (PC3), fibrosarcoma (HT1080), and breast (MDA-MB-231)]. cytotoxicity studies revealed that compounds - displayed potent cell growth inhibition (IC values in the range of 0.17-2.50 μM), comparable to, or better than, clinically used cisplatin (0.63-6.35 μM). Preliminary mechanistic studies using HeLa cells indicate that the cytotoxic effects of the compounds involve apoptosis induction through ROS accumulation. Compound also demonstrated significant inhibition of endothelial cell migration and tube formation in the angiogenesis process. Evaluation of the antitumor activity of compound in nude mice bearing cervical cancer cell (HeLa) xenografts indicated significant tumor growth inhibition (55%) with 1 mg/kg dose (every 3 days) compared with the same dose of cisplatin (28%). These results demonstrate the potential of gold(III) complexes containing cyclometalated triphenylphosphine sulfide ligands as novel metal-based anticancer agents.
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http://dx.doi.org/10.1021/acs.inorgchem.0c00423DOI Listing
April 2020

Fabrication of a novel ZnInS/g-CN/graphene ternary nanocomposite with enhanced charge separation for efficient photocatalytic H evolution under solar light illumination.

Photochem Photobiol Sci 2019 Dec 28;18(12):2952-2964. Epub 2019 Oct 28.

Department of Chemistry, National Institute of Technology, Warangal-506004, Telangana, India. and Centre for Advanced Materials, National Institute of Technology, Warangal-506004, Telangana, India.

Design and synthesis of efficient photocatalyst systems for a large volume of hydrogen (H) evolution under solar light is still a great challenge. To obtain high photocatalytic activity, graphene-based semiconductor photocatalysts are gaining heightened attention in the field of green and sustainable fuel production due to their good electronic properties, high surface area and chemical stability. Herein, we demonstrate an efficient, novel and smart architecture of a graphene-based ZnInS/g-CN nanojunction by a simple hydrothermal process for H generation. In the present study, graphene (G) is chosen as the electron mediator and ZnInS (ZIS) and g-CN (CN) are chosen as two different semiconductor photocatalysts to construct a smart architecture for the ternary photocatalytic system. Different characterization techniques such as XRD, TGA, FT-IR, SEM, TEM, HR-TEM, XPS, BET, and UV-vis DRS were employed to ensure the successful integration of graphene, ZnInS, and g-CN in the nanocomposite. As a result, high and efficient H evolution (477 μmol h g) is attained for the graphene-based ZnInS/g-CN nanocomposite. Transient photocurrent experiments, ESR, PL, and time-resolved PL studies suggested that the intimate ternary nanojunction effectively promotes fast charge transfer and thereby enhances photocatalytic H evolution.
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http://dx.doi.org/10.1039/c9pp00234kDOI Listing
December 2019

Facile conversion of zinc hydroxide carbonate to CaO-ZnO for selective CO gas detection.

J Colloid Interface Sci 2020 Jan 27;558:310-322. Epub 2019 Sep 27.

Centre for Advanced Materials and Industrial Chemistry (CAMIC), School of Science, College of Science, Engineering & Health, RMIT University, 124 La Trobe Street, Melbourne, Victoria 3001, Australia; School of Engineering, Electrical and Bio-medical Engineering, RMIT University, Melbourne, Victoria 3001, Australia. Electronic address:

Tailored synthesis of heterostructures for low temperature (sub 200 °C) CO sensing continues to be a challenging task. The present study demonstrates CO sensing characteristics of CaO-ZnO heterostructures achieved by zinc hydroxide carbonate (Zn(CO)(OH)) conversion to ZnO using Ca(OH) at 50 °C. Control samples namely, Zn(CO)(OH), Ca(OH), ZnO, and CaO integrated microsensors exhibited low sensitivity towards CO gas. However, CaO-ZnO heterostructures demonstrated significant sensitivity (26 to 91%) at 150 °C for gas concentration ranging from 100 to 10000 ppm, respectively. In this study, zinc hydroxide carbonate sensitized with 25 wt% Ca(OH) to form CaO-ZnO heterostructures (25CaZMS) displayed a promising sensitivity (77%) and selectivity (98%) towards 500 ppm CO gas. Moreover, the selectivity studies were conducted in the presence of 10 commonly found gases and their sensing performance was compared against CO gas in dry and humid conditions. The developed CaO-ZnO sensor exhibited faster kinetics in comparison to the control samples. Improved sensing performance observed here is attributed to the low-temperature synthesis route which resulted in a large number of active pores and high surface area morphology. Additionally, the high CO adsorption capacity of CaO combined with compatible n-type semiconductors in forming highly dynamic nano-interfaced heterostructure is a promising step towards developing a precise CO gas microsensor.
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http://dx.doi.org/10.1016/j.jcis.2019.09.103DOI Listing
January 2020

Unprecedented Formation of a Binuclear Au(II)-Au(II) Complex through Redox State Cycling: Electrochemical Interconversion of Au(I)-Au(I), Au(II)-Au(II), and Au(I)-Au(III) in Binuclear Complexes Containing the Carbanionic Ligand CFPPh.

Inorg Chem 2019 Oct 1;58(20):13999-14004. Epub 2019 Oct 1.

School of Science , RMIT University , GPO Box 2476, Melbourne , Victoria 3001 , Australia.

The rational design of binuclear Au(I)-Au(I), Au(II)-Au(II), and Au(I)-Au(III) complexes requires an understanding of how the redox states interconvert. Herein, the electrochemical interconversion of the three oxidation states I, II, and III is reported on the voltammetric (cyclic and rotating disk electrode) time scales for binuclear gold complexes containing CFPPh as a ligand, to demonstrate for the first time formation of a binuclear Au(II)-Au(II) from a Au(I)-Au(III) complex. Results are supported by bulk electrolysis and coulometry with reaction products being identified by P NMR and UV-vis spectroscopy. All electrochemical processes involve an overall two-electron charge-transfer process with no one-electron intermediate being detected. Importantly, the kinetically rather than thermodynamically favored isomer [AuX(μ-2-CFPPh)] is formed on redox cycling of [XAu(μ-2-CFPPh)(κ-2-CFPPh)AuX] (X = Cl, ONO). Finally, a mechanism is proposed to explain the simultaneous change of coordination of the chelating carbanionic ligand to bridging mode and interconversion of oxidation states in binuclear gold complexes.
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http://dx.doi.org/10.1021/acs.inorgchem.9b01983DOI Listing
October 2019

Mercury in natural gas streams: A review of materials and processes for abatement and remediation.

J Hazard Mater 2020 01 18;382:121036. Epub 2019 Aug 18.

Centre for Advanced Materials & Industrial Chemistry (CAMIC), School of Science, RMIT University, GPO Box 2476, Melbourne, VIC, 3001, Australia. Electronic address:

The role of natural gas in mitigating greenhouse gas emissions and advancing renewable energy resource integration is undoubtedly critical. With the progress of hydrocarbons exploration and production, the target zones become deeper and the possibility of mercury contamination increases. This impacts on the industry from health and safety risks, due to corrosion and contamination of equipment, to catalyst poisoning and toxicity through emissions to the environment. Especially mercury embrittlement, being a significant problem in LNG plants using aluminum cryogenic heat exchangers, has led to catastrophic plant incidents worldwide. The aim of this review is to critically discuss the conventional and alternative materials as well as the processes employed for mercury removal during gas processing. Moreover, comments on studies examining the geological occurrence of mercury species are included, the latest developments regarding the detection, sampling and measurement are presented and updated information with respect to mercury speciation and solubility is displayed. Clean up and passivation techniques as well as disposal methods for mercury-containing waste are also explained. Most importantly, the environmental as well as the health and safety implications are addressed, and areas that require further research are pinpointed.
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http://dx.doi.org/10.1016/j.jhazmat.2019.121036DOI Listing
January 2020

Pyrazolo-benzothiazole hybrids: Synthesis, anticancer properties and evaluation of antiangiogenic activity using in vitro VEGFR-2 kinase and in vivo transgenic zebrafish model.

Eur J Med Chem 2019 Nov 8;182:111609. Epub 2019 Aug 8.

Academy of Scientific and Innovative Research (AcSIR), CSIR-Human Resource Development Centre (CSIR-HRDC) Campus, Ghaziabad, 201 002, Uttar Pradesh, India; Department of Organic Synthesis & Process Chemistry, CSIR-Indian Institute of Chemical Technology (IICT), Hyderabad, 500 007, India; Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad, 500 037, India; School of Pharmaceutical Education and Research (SPER), Jamia Hamdard, New Delhi, 110 062, India. Electronic address:

A series of new pyrazolo-benzothiazole hybrids (7-26) were synthesised and screened for their cytotoxic activity towards several cancer cell lines [colon (HT-29), prostate (PC-3), lung (A549), glioblastoma (U87MG)] and normal human embryonic kidney cell line (Hek-293T). Compounds 8, 9, 13, 14, 18, 19, 23, and 24 displayed significant activity, with compound 14 being particularly potent towards all the tested cancer cell lines with IC values in the range 3.17-6.77 μM, even better than reference drug axitinib (4.88-21.7 μM). Compound 14 also showed the strongest growth inhibition in 3D multicellular spheroids of PC-3 and U87MG cells. The mechanism of cellular toxicity in PC-3 cells was found to be cell cycle arrest and apoptosis induction through depolarisation of mitochondrial membrane potential, increased ROS production and subsequent DNA damage. Further, compound 14 displayed significant in vitro (VEGFR-2 inhibition) and in vivo [transgenic zebrafish Tg(flila:EGFP) model] antiangiogenic properties. Overall, these results provide strong evidence that compound 14 could be considered for a lead candidate in anticancer and antiangiogenic drug discovery.
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http://dx.doi.org/10.1016/j.ejmech.2019.111609DOI Listing
November 2019

Potent and Selective Cytotoxic and Anti-inflammatory Gold(III) Compounds Containing Cyclometalated Phosphine Sulfide Ligands.

Chemistry 2019 Nov 30;25(62):14089-14100. Epub 2019 Sep 30.

Centre for Advanced Materials & Industrial Chemistry (CAMIC), School of Science, RMIT University, GPO BOX 2476, Melbourne, 3001, Australia.

Four cycloaurated phosphine sulfide complexes, [Au{κ -2-C H P(S)Ph } ][AuX ] [X=Cl (2), Br (3), I (4)] and [Au{κ -2-C H P(S)Ph } ]PF (5), have been prepared and thoroughly characterized. The compounds were found to be stable under physiological-like conditions and showed excellent cytotoxicity against a broad range of cancer cell lines and remarkable cytotoxicity in 3D tumor spheroids. Mechanistic studies with cervical cancer (HeLa) cells indicated that the cytotoxic effects of the compounds involve the inhibition of thioredoxin reductase and induction of apoptosis through mitochondrial disruption. In vivo experiments in nude mice bearing HeLa xenografts showed that treatment with compounds 4 and 5 resulted in significant inhibition of tumor growth (35.8 and 46.9 %, respectively), better than that of cisplatin (29 %). The newly synthesized gold complexes were also evaluated for their in vitro and in vivo anti-inflammatory activity through the study of lipopolysaccharide (LPS)-activated macrophages and carrageenan-induced hind paw edema in rats, respectively.
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http://dx.doi.org/10.1002/chem.201903388DOI Listing
November 2019

Process optimization using response surface methodology for the removal of thorium from aqueous solutions using rice-husk.

Chemosphere 2019 Dec 30;237:124488. Epub 2019 Jul 30.

Center for Advanced Materials and Industrial Chemistry (CAMIC), School of Science, RMIT University, Victoria, 3001, Australia. Electronic address:

The adsorptive capability of rice-husk for the sorption of thorium ions from aqueous solutions in batch mode was studied. The key process variables (initial metal ion concentration, initial solution pH and S/L (solid-to-liquid ratio) were optimized for achieving maximum bioremoval efficiency (B%) by employing the Box-Behnken design (33) in response surface methodology (RSM). A quadratic model developed by fitting the experimental data predicted 93% of the responses and estimated the local maximum of B% as >99% for an initial ThIV concentration of 150  g/L, S/L ratio of 5, and an initial pH of 4, and the reported biosorption capacity (qe) is 15.95 mg/g for the same conditions. Freundlich isotherm (R = 0.9841) and pseudo-first-order (R = 0.9416) kinetic models had the best concurrence with the experimental data in the thorium concentration range used implying the sorption mechanism involves surface biosorption and intraparticle diffusion.
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http://dx.doi.org/10.1016/j.chemosphere.2019.124488DOI Listing
December 2019

Zinc Titanate Nanoarrays with Superior Optoelectrochemical Properties for Chemical Sensing.

ACS Appl Mater Interfaces 2019 Aug 5;11(32):29255-29267. Epub 2019 Aug 5.

School of Engineering , RMIT University , Melbourne 3001 , Victoria , Australia.

In this report, the gas sensing performance of zinc titanate (ZnTiO) nanoarrays (NAs) synthesized by coating hydrothermally formed zinc oxide (ZnO) NAs with TiO using low-temperature chemical vapor deposition is presented. By controlling the annealing temperature, diffusion of ZnO into TiO forms a mixed oxide of ZnTiO NAs. The uniformity and the electrical properties of ZnTiO NAs made them ideal for light-activated acetone gas sensing applications for which such materials are not well studied. The acetone sensing performance of the ZnTiO NAs is tested by biasing the sensor with voltages from 0.1 to 9 V dc in an amperometric mode. An increase in the applied bias was found to increase the sensitivity of the device toward acetone under photoinduced and nonphotoinduced (dark) conditions. When illuminated with 365 nm UV light, the sensitivity was observed to increase by 3.4 times toward 12.5 ppm acetone at 350 °C with an applied bias of 9 V, as compared to dark conditions. The sensor was also observed to have significantly reduced the adsorption time, desorption time, and limit of detection (LoD) when excited by the light source. For example, LoD of the sensor in the dark and under UV light at 350 °C with a 9 V bias is found to be 80 and 10 ppb, respectively. The described approach also enabled acetone sensing at an operating temperature down to 45 °C with a repeatability of >99% and a LoD of 90 ppb when operated under light, thus indicating that the ZnTiO NAs are a promising material for low concentration acetone gas sensing applications.
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http://dx.doi.org/10.1021/acsami.9b08704DOI Listing
August 2019

CoO needles on Au honeycomb as a non-invasive electrochemical biosensor for glucose in saliva.

Biosens Bioelectron 2019 Sep 26;141:111479. Epub 2019 Jun 26.

Centre for Advanced Materials and Industrial Chemistry (CAMIC), School of Science, RMIT University, Melbourne, Victoria, 3001, Australia. Electronic address:

While glucose monitoring technology is widely available, the continued prevalence of diabetes around the world coupled with its debilitating effects continues to grow. The significant limitations which exist in the current technology, instils the need for materials capable of non-invasive glucose detection. In this study a unique non-enzymatic electrochemical glucose sensor was developed, utilising a gold honeycomb-like framework upon which sharp CoO needles are anchored. This composite nanomaterial demonstrates excellent sensing performance in glucose concentrations ranging between 20 μM and 4 mM, exceeding the range required for non-invasive glucose sensing. In conjunction with this high sensitivity (2.014 mA mM·cm), the material possesses excellent selectivity towards glucose for commonly interfering physiological species such as uric acid and ascorbic acid. Glucose detection in synthetic saliva was then performed showing excellent capability in the low concentration range (20 μM-1 mM) for non-invasive sensing performance. Further tests showed good selectivity of the sensor in physiological contaminants commonly found in saliva such as cortisol and dopamine. This development provides excellent scope to create next-generation non-invasive diabetes monitoring platforms, with excellent performance when detecting low glucose concentrations in complex solutions such as saliva.
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http://dx.doi.org/10.1016/j.bios.2019.111479DOI Listing
September 2019

Synthesis and in vitro cytotoxicity evaluation of β-carboline-combretastatin carboxamides as apoptosis inducing agents: DNA intercalation and topoisomerase-II inhibition.

Bioorg Med Chem 2019 08 6;27(15):3285-3298. Epub 2019 Jun 6.

Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad 500 037, India; Medicinal Chemistry and Biotechnology, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India; School of Pharmaceutical Education and Research (SPER), Jamia Hamdard, New Delhi 110 062, India. Electronic address:

To explore a new set of cytotoxic agents, β-carboline-combretastatin carboxamide conjugates were designed, synthesized and evaluated for their in vitro cytotoxicity potential, DNA binding affinity and Topoisomerase-II (topo-II) inhibition activity. Among the designed hybrids, 10v and 10af have shown significant cytotoxic effect against A549 (lung cancer) cell line having IC value 1.01 µM and 1.17 µM respectively. Further, it was speculated that treatment with compound 10v may induce apoptosis among A549 cells, which was supported by Hoechst staining, DCFDA, Annexin V-FITC and morphological assays. Flow cytometric analysis revealed that the hybrid 10v arrests A549 cells in G2/M phase of cell cycle in a dose dependent manner. Amongst the active hybrids, most potent hybrid 10v was tested for DNA topo-II inhibition activity. Moreover, to further support the biological activity and to infer the mode of interaction between ligands and DNA, spectroscopy and molecular docking studies were carried out. The docking and spectroscopy results showed that the ligands exhibited an intercalative mode of binding with DNA and could efficiently bind to DNA and form topo-II ternary complex. Based on these experiments, the hybrids 10v and 10af were identified as proficient new scaffolds which need to be developed as hit molecules for therapeutic interest.
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http://dx.doi.org/10.1016/j.bmc.2019.06.007DOI Listing
August 2019

CeO-Decorated ?-MnO Nanotubes: A Highly Efficient and Regenerable Sorbent for Elemental Mercury Removal from Natural Gas.

Langmuir 2019 Jun 11;35(25):8246-8256. Epub 2019 Jun 11.

Centre for Advanced Materials & Industrial Chemistry (CAMIC), School of Science , RMIT University , GPO Box 2476, Melbourne , Victoria 3001 , Australia.

CeO nanoparticle-decorated ?-MnO nanotubes (NTs) were prepared and tested for elemental mercury (Hg) vapor removal in simulated natural gas mixtures at ambient conditions. The composition which had the largest surface area and a relative Ce/Mn atomic weight ratio of around 35% exhibited a maximum Hg uptake capacity exceeding 20 mg?g (2 wt %), as determined from measurements of mercury breakthrough which corresponded to 99.5% Hg removal efficiency over 96 h of exposure. This represents a significant improvement in the activity of pure metal oxides. Most importantly, the composite nanosorbent was repeatedly regenerated at 350 ?C and retained the 0.5% Hg breakthrough threshold. It was projected to be able to sustain 20 regeneration cycles, with the presence of acid gases, CO, and HS, not affecting its performance. This result is particularly important, considering that pure CeO manifests rather poor activity for Hg removal at ambient conditions, and hence, a synergistic effect in the composite nanomaterial was observed. This possibly results from the addition of facile oxygen vacancy formation at ?-MnO NTs and the increased amount of surface-adsorbed oxygen species.
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http://dx.doi.org/10.1021/acs.langmuir.9b00835DOI Listing
June 2019

Using colloidal lithography to control the formation of gas sorption sites through galvanic replacement reaction.

J Colloid Interface Sci 2019 Jul 1;547:199-205. Epub 2019 Apr 1.

Centre for Advanced Materials and Industrial Chemistry (CAMIC), School of Science, RMIT University, Melbourne 3000, Australia. Electronic address:

Using colloidal lithography, a series of inverted long-range ordered crystals (i-LROCs) of Pd honeycombs were fabricated on quartz crystal microbalance (QCM) sensors. The structures formed provided the required platform for the proceeding galvanic replacement reaction (GR) process to generate seamless Au nanoparticle deposits throughout the i-LROC. The results showed that controlling the dimensions of the pores in the developed Pd i-LROCs is important in the formation of gold deposition sites on the uniform structures through the GR reaction process. The developed Pd/Au i-LROC deposited sensors showed significant enhancement in the sensitivity toward Hg vapor when compared to pure Pd structures, with limit of detection improving from 60.0 to 13.7 µg/m, respectively. Furthermore, a significant improvement in the modified sensor's selectivity toward Hg in the presence of other industrial related gas species was observed which is attributed to the addition of Au to the Pd structures through GR reaction.
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http://dx.doi.org/10.1016/j.jcis.2019.04.001DOI Listing
July 2019

Functionalization of Elongated Tetrahexahedral Au Nanoparticles and Their Antimicrobial Activity Assay.

ACS Appl Mater Interfaces 2019 Apr 1;11(14):13450-13459. Epub 2019 Apr 1.

Department of Biotechnology and Genetic Engineering , Jahangirnagar University , Savar , Dhaka 1342 , Bangladesh.

Gold nanoparticles are inert for the human body, and therefore, they have been functionalized to provide them with antibacterial properties. Here, elongated tetrahexahedral (ETHH) Au nanoparticles were synthesized, characterized, and functionalized with lipoic acid (LA), a natural antioxidant with a terminal carboxylic acid and a dithiolane ring, to generate ETHH-LA Au nanoparticles. The antioxidant activity of Au nanoparticles was investigated in vitro, showing that LA enhances the 2,2-diphenyl-1-picrylhydrazyl free-radical scavenging and Fe ion reducing activity of ETHH-LA at higher amounts. The antimicrobial propensities of the nanoparticles were investigated against Gram-positive ( Bacillus subtilis) and Gram-negative ( Escherichia coli) bacteria through propidium iodide assay as well as disk diffusion assay. ETHH-LA Au nanoparticles showed significantly higher antimicrobial activity against B. subtilis compared with E. coli. Furthermore, ETHH-LA Au nanoparticles also showed significantly better antimicrobial activity against both bacterial strains when compared with ETHH. ETHH Au nanoparticles also bring about the oxidation of bacterial cell membrane fatty acids and produce lipid peroxides. ETHH-LA showed higher lipid peroxidation potential than that of ETHH against both bacteria tested. The hemolytic potential of Au nanoparticles was investigated using human red blood cells and ETHH-LA showed reduced hemolytic activity than that of ETHH. The cytotoxicity of Au nanoparticles was investigated using human cervical cancer cells, HeLa, and ETHH-LA Au nanoparticles showed reduced cytotoxicity than that of ETHH. Taken together, LA enhances the antimicrobial activity of ETHH Au nanoparticles and Au nanoparticles interact with the bacteria through electrostatic interactions as well as hydrophobic interactions and damage the bacterial cell wall followed by oxidation of cell membrane fatty acids.
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http://dx.doi.org/10.1021/acsami.9b02279DOI Listing
April 2019

Synthesis, anti-proliferative and apoptosis-inducing studies of palladacycles containing a diphosphine and a Sn,As-based chelate ligand.

Dalton Trans 2019 Apr;48(16):5183-5192

Centre for Advanced Materials & Industrial Chemistry (CAMIC), School of Science, RMIT University, GPO BOX 2476, Melbourne 3001, Australia.

Cleavage of the bromide bridges in [Pd2(μ-Br)2{κ2(Sn,As)-2-MeBrSnC6F4AsPh2}2] (1) by diphosphine ligands gave the mono- and dinuclear palladacycles [Pd(L)Br{κ2(Sn,As)-2-MeBrSnC6F4AsPh2}] [L = dppe (2) dppm (3), ortho-dppBz (4)] and [Pd2Br2(para-dppBz){κ2(Sn,As)-2-MeBrSnC6F4AsPh2}2] (5). The interactions of these complexes with DNA (CT-DNA) and proteins (human serum albumin) were studied by UV-Vis and fluorescence spectroscopy, respectively. The results confirmed the interaction of these palladium complexes with CT-DNA through groove binding, and their strong binding affinity to HSA. The anti-proliferative activities of complexes 1-5 were tested against four human cancer cell lines (HeLa, A549, PC-3, and HT1080) and normal keratinocytes (HaCaT). Among the series, the palladium(ii) complex containing the 1,2-bis(diphenylphosphino)benzene ligand (4) showed the highest cytotoxicity against HeLa, PC-3 and HT1080 cells, with IC50 values of 0.25 ± 0.08, 0.85 ± 0.11, and 0.66 ± 0.15 μM, respectively. Interestingly, compound 4 exhibited lower cytotoxic activity toward normal HaCaT cells (IC50 = 4.65 ± 0.16 μM). Additionally, this complex exhibited lower toxicity and better anti-cancer activity than cisplatin. Further mechanistic studies, including Hoechst staining and flow cytometry, confirmed that complex 4 induced G2/M phase cell cycle arrest and apoptotic cell death in HeLa cells.
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http://dx.doi.org/10.1039/c8dt03875aDOI Listing
April 2019

Preparation of Au nanoparticles on a magnetically responsive support via pyrolysis of a Prussian blue composite.

J Colloid Interface Sci 2019 Mar 8;540:563-571. Epub 2019 Jan 8.

Centre for Advanced Materials and Industrial Chemistry (CAMIC), School of Science, RMIT University, GPO Box 2476, Melbourne, VIC 3001, Australia. Electronic address:

A strategy is described for the direct preparation of Au nanoparticles (AuNPs) on a Fe-based support, coated with porous carbon (PC), via pyrolysis of an AuCN functionalised Prussian Blue (PB) metal organic framework (MOF). The composite starting material was prepared with an even distribution of AuCN on the surface via galvanic exchange of PB with a gold salt in solution. The resulting structures after pyrolysis were shown to be active Au-based nanomaterials for model applications including catalysis (4-nitrophenol reduction) and electroanalysis (arsenic (III) detection), suggesting broad application where Au nanoparticles are required at a liquid-solid interface. The Fe based support was seen to consist of Fe, FeC and FeC phases, and the carbon coating increased the stability and improved the conductivity of the materials. The temperature of pyrolysis was seen to affect the activity of the supported nanoparticles, with an increased Au surface area obtained at the higher pyrolysis temperature (650 °C) tested. A general strategy is thus confirmed for preparation of noble metal nanoparticles evenly distributed on a magnetic support, allowing easy separation of catalysts from products in heterogeneous applications.
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http://dx.doi.org/10.1016/j.jcis.2019.01.027DOI Listing
March 2019

Ranolazine-Functionalized Copper Nanoparticles as a Colorimetric Sensor for Trace Level Detection of As.

Nanomaterials (Basel) 2019 Jan 10;9(1). Epub 2019 Jan 10.

Centre for Advanced Materials and Industrial Chemistry (CAMIC), School of Applied Sciences, RMIT University, GPO BOX 2476, Melbourne 3001, Australia.

This study involves environmentally friendly synthesis of copper nanoparticles in aqueous medium without inert gas protection, using ranolazine as a capping material. UV-Visible (UV-Vis) spectrometry showed that ranolazine-derived copper nanoparticles (Rano-Cu NPs) demonstrate a localized surface plasmon resonance (LSPR) band at 573 nm with brick-red color under optimized parameters, including pH, reaction time, and concentrations of copper salt, hydrazine hydrate, and ranolazine. The coating of ranolazine on the surface of Cu NPs was studied via Fourier transform infrared (FTIR) spectroscopy. Scanning electron microscopy (SEM) revealed that Rano-Cu NPs consist of spherical particles. X-ray diffraction (XRD) verified that Rano-Cu NPs are crystalline in nature. Atomic force microscopy (AFM) showed that the average size of Rano-Cu NPs was 40 ± 2 nm in the range of 22⁻95 nm. Rano-Cu NPs proved to be highly sensitive as a selective colorimetric sensor for As via color change from brick red to dark green, in the linear range of 3.0 × 10 to 8.3 × 10 M, with an R² value of 0.9979. The developed sensor is simple, cost effective, highly sensitive, and extremely selective for As detection, showing a low detection limit (LDL) of 1.6 × 10 M. The developed sensor was effectively tested for detection of As in some water samples.
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http://dx.doi.org/10.3390/nano9010083DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6359034PMC
January 2019

Single step formation of biocompatible bimetallic alloy nanoparticles of gold and silver using isonicotinylhydrazide.

Mater Sci Eng C Mater Biol Appl 2019 Mar 22;96:286-294. Epub 2018 Nov 22.

Nano-Bio interfacial research laboratory (NBIRL), Department of Biotechnology, Siddaganga Institute of Technology, Tumkur 572103, Karnataka, India; Centre for Advanced Materials and Industrial Chemistry, School of Science, RMIT University, Melbourne, VIC 3001, Australia; Amity Institute of Biotechnology, Amity University Rajasthan, Kant Kalwar, NH-11C, Jaipur-Delhi highway, Jaipur 303002, Rajasthan, India. Electronic address:

Manufacturing nanoparticles with controlled physicochemical properties using environment-friendly routes have potential to open new prospects for a variety of applications. Accordingly, several approaches have been established for manufacturing metal nanoparticles. Many of these approaches entail the use of hazardous chemicals and could be toxic to the environment, and cannot be used readily for biomedical applications. In the present work, we report a single step bio-friendly approach to formulate gold (Au), silver (Ag), and Au-Ag alloy nanoparticles with desired surface corona and composition using isonicotinylhydrazide (INH) as a reducing agent. INH also functioned as a stabilizing agent by enabling a surface corona around the nanoparticles. Remarkably, within a single step INH could also provide a handle in regulating the composition of Au and Ag in bimetallic systems without any additional chemical modification. The physicochemical and surface properties of the different nanoparticles thus obtained have been examined by analytical, spectroscopic and microscopic techniques. Cell cytotoxicity (release of lactate dehydrogenase), cell viability and intracellular reactive oxygen species (ROS) assays confirmed that the Au, Ag, and Au-Ag bimetallic nanoparticles prepared with INH are biocompatible. Finally, the presence of organic surface corona of INH on the nanoparticles was found to impart nanozyme activity and antimycobacterial sensitivity to the nanoparticles.
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http://dx.doi.org/10.1016/j.msec.2018.11.024DOI Listing
March 2019

Role of Ceria in the Design of Composite Materials for Elemental Mercury Removal.

Chem Rec 2019 Jul 10;19(7):1407-1419. Epub 2018 Dec 10.

Centre for Advanced Materials and Industrial Chemistry (CAMIC), School of Science, RMIT University, GPO BOX 2476, Melbourne, VIC 3001, Australia.

The necessity to drastically act against mercury pollution has been emphatically addressed by the United Nations. Coal-fired power plants contribute a great deal to the anthropogenic emissions; therefore, numerous sorbents/catalysts have been developed to remove elemental mercury (Hg ) from flue gases. Among them, ceria (CeO ) has attracted significant interest, due to its reversible Ce /Ce redox pair, surface-bound defects and acid-base properties. The removal efficiency of Hg vapor depends among others, on the flue gas composition and temperature. CeO can be incorporated into known materials in such a way that the abatement process can be effective at different operating conditions. Hence, the scope of this account is to discuss the role of CeO as a promoter, active phase and support in the design of composite Hg sorbents/catalysts. The elucidation of each of these roles would allow the integration of CeO advantageous characteristics to such degree, that tailor-made environmental solution to complex issues can be provided within a broader application scope. Besides, it would offer invaluable input to theoretical calculations that could enable the materials screening and engineering at a low cost and with high accuracy.
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http://dx.doi.org/10.1002/tcr.201800161DOI Listing
July 2019

Silicon as a ubiquitous contaminant in graphene derivatives with significant impact on device performance.

Nat Commun 2018 11 29;9(1):5070. Epub 2018 Nov 29.

Intelligent Polymer Research Institute & ARC Centre of Excellence for Electromaterials Science, Australian Institute for Innovative Materials, University of Wollongong, Wollongong, NSW, 2522, Australia.

Silicon-based impurities are ubiquitous in natural graphite. However, their role as a contaminant in exfoliated graphene and their influence on devices have been overlooked. Herein atomic resolution microscopy is used to highlight the existence of silicon-based contamination on various solution-processed graphene. We found these impurities are extremely persistent and thus utilising high purity graphite as a precursor is the only route to produce silicon-free graphene. These impurities are found to hamper the effective utilisation of graphene in whereby surface area is of paramount importance. When non-contaminated graphene is used to fabricate supercapacitor microelectrodes, a capacitance value closest to the predicted theoretical capacitance for graphene is obtained. We also demonstrate a versatile humidity sensor made from pure graphene oxide which achieves the highest sensitivity and the lowest limit of detection ever reported. Our findings constitute a vital milestone to achieve commercially viable and high performance graphene-based devices.
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http://dx.doi.org/10.1038/s41467-018-07396-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6265250PMC
November 2018
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