Publications by authors named "Zhanhu Guo"

148 Publications

Synergistic effect of carboxymethylcellulose and Cryptococcus laurentii on suppressing green mould of postharvest grapefruit and its mechanism.

Int J Biol Macromol 2021 Mar 26;181:253-262. Epub 2021 Mar 26.

Key Laboratory for Forest Resources Conservation and Use in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming 650224, China; Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Southwest China, Southwest Forestry University, Kunming 650224, China. Electronic address:

The synergistic effects of carboxymethylcellulose (CMC) combined with Cryptococcus laurentii FRUC DJ1 were studied on controlling green mould resulting from Penicillium digitatum in grapefruit fruit. The results indicate that both C. laurentii and the CMC treatment suppressed P. digitatum conidia germination. In addition, C. laurentii growth in vitro was not affected by low CMC concentrations, nevertheless, the biofilm of C. laurentii was enhanced. Compared with the control fruit, the grapefruit had a lower green mould in all treatments. Significantly synergistic effects were caused by combining C. laurentii and CMC on minimum decay incidence and lesion diameter. Combined treatment induced defence enzyme activities, including chitinase, β-1,3-glucanase, peroxidase, polyphenol oxidase, and phenylalanine ammonia-lyase, together with disease tolerance-associated total phenol. Also, this combination inhibited the pathogen growth by adhered to the hyphae and reduced its infection in fruit wounds. Moreover, the commercial quality parameters in the combined treatment of C. laurentii and CMC, including weight loss, total soluble solids, ascorbic acid, and titratable acidity, were superior to single treatment. The combination of C. laurentii and CMC can not only control postharvest decay but also maintain fruit qualities. Thus, it can be used in grapefruit for commercial purposes.
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http://dx.doi.org/10.1016/j.ijbiomac.2021.03.155DOI Listing
March 2021

In-situ synthesis of uranyl-imprinted nanocage for selective uranium recovery from seawater.

Angew Chem Int Ed Engl 2021 Feb 16. Epub 2021 Feb 16.

State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University,, State Key Laboratory of Marine Resource Utilization in South China Sea, No. 58, Renmin Avenue, Haikou, Hainan Province, 570228, 577028, Haikou, CHINA.

Adaptive coordination structure is vital for selective uranium extraction from seawater. By strategy of molecular imprinting, uranyl is introduced into the  m ultivariate metal-organic framework (MOF) during the synthesis process to guide the  in-situ  construction of proper nanocage structure for targeting uranyl binding. Except for  the  coordination between uranium with four oxygen from the materials, the axial oxygen of uranyl also forms hydrogen bonds with hydrogen from the phenolic hydroxyl group, which enhances the binding affinity of the material to uranyl. Attributing to the high binding affinity, the adsorbent shows high uranium binding selectivity to uranyl against not only the interfering metal ions, but also the carbonate group that coordinates with uranyl to form [UO 2 (CO) 3 ] 4 -  in seawater. In natural seawater, the adsorbent realizes a high uranium adsorption capacity of 7.35 mg g -1 , t ogether with an 18.38 times higher selectivity to vanadium.  Integrated into account the high reusability, this adsorbent is a promising alternative for uranium recovery from seawater.
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http://dx.doi.org/10.1002/anie.202101015DOI Listing
February 2021

Understanding the varying mechanisms between the conformal interlayer and overlayer in the silicon/hematite dual-absorber photoanode for solar water splitting.

Dalton Trans 2021 Feb 8;50(8):2936-2944. Epub 2021 Feb 8.

Henan Joint International Research Laboratory of Nanocomposite Sensing Materials, School of Chemical and Environmental Engineering, Anyang Institute of Technology, Anyang 455000, China.

Dual-absorber photoelectrodes have been proved to have great potential in the photoelectrochemical (PEC) water splitting application due to their broadband absorption and suitable energy-band position, while the surface/interface issues are still not clearly resolved and understood. Here, during the preparation of a silicon/hematite dual-absorber photoanode achieved via synthesizing a Sn-doped hematite film on the silicon nanowire (SiNW) substrate, we separately introduced the conformal overlayer and interlayer of an AlO thin film by atomic layer deposition. With the thickness-optimized interlayer (overlayer) of the AlO thin film, the photocurrent density at 1.23V can be enhanced from 0.85 mA cm to 1.51 mA cm (1.25 mA cm), and the on-set potential has a cathodic shift of ∼0.32 V. Although both the overlayer and interlayer modification can substantially improve the PEC performance, the underlying mechanisms are obviously different. The overlayer can only reduce the carrier recombination on the top surface and in the bulk of the hematite film; in contrast, the interlayer not only passivates the SiNW surface and bottom surface of the hematite film, but also the top surface of the photoanode due to Al thermal diffusion from the bottom to the top surface of the hematite film and the resultant AlO formation. This work deepens our understanding for the roles of the surface and interface engineering in the achievement of high-performance PEC systems based on dual or more absorbers.
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http://dx.doi.org/10.1039/d0dt03486jDOI Listing
February 2021

Advances in Waterborne Acrylic Resins: Synthesis Principle, Modification Strategies, and Their Applications.

ACS Omega 2021 Feb 21;6(4):2443-2449. Epub 2021 Jan 21.

Integrated Composites Laboratory (ICL), Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States.

Waterborne acrylic resin is a kind of environmental protection resin, which is widely used in coatings, bridges, ships, and locomotives. In order to be better used in various fields, modification of waterborne acrylic resin has attracted much attention. In this paper, we introduce the method to synthesize waterborne acrylic resins, the composition of the resin, and basic properties of each monomer. According to the requirements of different properties of the resin, the modification mechanism and methods of the resin are discussed, including thermal performance, corrosion resistance, mechanical property, and water resistance. The applications of waterborne acrylic resin in the construction, automobile, metal anticorrosion, and furniture industries are discussed with detailed examples. Finally, the prospect of waterborne acrylic resin is proposed.
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http://dx.doi.org/10.1021/acsomega.0c05593DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7859933PMC
February 2021

The recent progress of synergistic supramolecular polymers: preparation, properties and applications.

Chem Commun (Camb) 2021 Feb;57(12):1413-1429

Integrated Composites Laboratory (ICL), Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996, USA.

Supramolecular polymers have the combined properties of both traditional polymers and supramolecules. They are generally formed via the self-assembled polymerization driven noncovalent interactions such as hydrogen bonding, π-π stacking, metal coordination, and host-guest interaction between building blocks. The driving force for the formation of supramolecular polymers has changed from single noncovalent interactions to multiple noncovalent interactions. The advantages of multiple noncovalent interactions driving the formation of supramolecular polymers are reviewed from four aspects: polymer construction, the enhancement of bonding strength, properties and topological structure. The applications are illustrated with detailed examples including self-healing, drug delivery, bioimaging, biomedicine, environmental sensing and electronics.
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http://dx.doi.org/10.1039/d0cc07247hDOI Listing
February 2021

Excellent selectivity and high capacity of As (V) removal by a novel lignin-based adsorbent doped with N element and modified with Ca.

Int J Biol Macromol 2021 Mar 5;172:299-308. Epub 2021 Jan 5.

Integrated Composites Laboratory (ICL), Department of Chemical and Bimolecular Engineering, University of Tennessee, Knoxville, TN 37996, USA. Electronic address:

As one of the most significant natural polymer with the highest annual yield, lignin has been applied in the treatment of wastewater to remove heavy metal ions. However, there are still some shortages, such as low reactivity, difficulties in adsorbing oxyanions and low selectivity on specific oxyanions. To improve its adsorption properties, a novel lignin-based adsorbent was prepared in this study, doped with nitrogen by Mannich reaction, using triethylenetetramine (TETA) as N source, and further modified with Ca. The adsorption of Ca, N-co-doped lignin (Ca@N-Lig) for As (V), Cr (VI) and P (V) was studied. The Ca@N-Lig shows high capacity, excellent selectivity and prominent regeneration ability for As (V) adsorption. The adsorption of Ca@N-Lig for As (V) followed the Langmuir isotherm model and the pseudo-second-order kinetics model, yielding a maximum adsorption capacity of 681.59 mg·g and a fast adsorption equilibrium within 30 min. Ca@N-Lig has an excellent regeneration ability on the adsorption of As (V) with a decrease of about 15.60% after 5 adsorption/desorption cycles. This study offers an efficient way to remove As (V) from polluted water.
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http://dx.doi.org/10.1016/j.ijbiomac.2021.01.007DOI Listing
March 2021

Influences of aggressive ions in human plasma on the corrosion behavior of AZ80 magnesium alloy.

Mater Sci Eng C Mater Biol Appl 2021 Feb 21;119:111521. Epub 2020 Sep 21.

Integrated Composites Lab (ICL), Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, TN 37966, USA. Electronic address:

Magnesium alloys can work as biomedical materials due to their Young's modules similar to that of bone. Nevertheless, in a human plasma, one of the major drawbacks of these materials is the low corrosion resistance. Here, AZ80 corrosion in the solutions containing chloride, bicarbonate, sulphate and hydrogen phosphate ions were investigated by a short-term immersion test and electrochemical techniques. The results showed that bicarbonate and hydrogen phosphate could retard corrosion rate, while chloride and sulphate accelerated corrosion rate. During the early immersion stage, the corrosion rate increased with the presence of bicarbonate. It was caused by the reaction of bicarbonate and hydroxide promoting the dissolution of magnesium and accelerating corrosion. In the later stage, the reduced corrosion rate was due to the formation of various protective films. The sample formed a new sparse porous MgSO·5HO compounds in the sulphate ion solution, which could not effectively prevent chloride ions from entering the matrix and thus accelerated the dissolution of magnesium. With the presence of hydrogen phosphate, magnesium phosphate with a much lower solubility was formed, preferentially precipitated on the surface and was not influenced by the chloride ions. The corrosion mechanisms of magnesium alloys in above ions were proposed.
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http://dx.doi.org/10.1016/j.msec.2020.111521DOI Listing
February 2021

Narrow pH response multilayer films with controlled release of ibuprofen on magnesium alloy.

Mater Sci Eng C Mater Biol Appl 2021 Jan 24;118:111414. Epub 2020 Aug 24.

College of Engineering and Computer Science, Arkansas State University, Jonesboro, AR 72467, USA. Electronic address:

An intelligent narrow pH-triggered multilayer film was prepared on magnesium alloys, aiming to solve the implant infections during the implantation period and improve the corrosion resistance of magnesium alloys. The encapsulation of ibuprofen by chitosan (IBU@CS) makes the release of IBU sensitive to narrow pH (pH 6.8-7.4). Positive charged IBU@CS was assembled with heparin (Hep) to fabricate (Hep/IBU@CS) film on AZ31 alloys using layer-by-layer method. The microstructure, composition and anticorrosion properties of the film were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and electrochemical experiments. Cellular activity was studied by MTT cell viability assay. The results showed that the Hep/IBU@CS multilayer films improved the corrosion resistance of magnesium alloys. The in vitro test demonstrated that the release of IBU in the film presented narrow pH sensitivity. The films showed no obvious signs of cytotoxicity conformed by the MTT assay and presented antibacterial properties. These preliminary results demonstrate the potential use of the Hep/IBU@CS multilayer films on magnesium-based implants.
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http://dx.doi.org/10.1016/j.msec.2020.111414DOI Listing
January 2021

Chemical characteristic and bioactivity of hemicellulose-based polysaccharides isolated from Salvia miltiorrhiza.

Int J Biol Macromol 2020 Dec 21;165(Pt B):2475-2483. Epub 2020 Oct 21.

Integrated Composites Laboratory (ICL), Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996, USA.

Salvia miltiorrhiza roots (SMRs), the main component of cell wall from the residual waste extraction, differ depending on the forming ways of monosaccharides. The extraction from 8% sodium hydroxide solution (H-8) was characterized by gel permeation chromatography (GPC), monosaccharide composition, Fourier transform infrared spectroscopy (FT-IR), and nuclear magnetic resonance (NMR) spectroscopy. The structure model of hemicellulose-based polysaccharides (HBPs) was derived by combining one-dimensional and two-dimensional NMR. Monosaccharides difference and correlation were performed by partial least square analysis (PLS). Seven H-8s exhibited optimal inhibitory activities, which varied based on different sources of Danshen. The backbone structure indicated that 4-β-D-Xylp served as the main chain connected by 3-α-L-Araf or 5-α-L-Araf-1, 4-β-D-Galp, and β-D-Glcp branch, as well as α-L-Rhap, α-D-GalpA and α-D-GlcpA fragments. The variation of HBPs in terms of the structure and bioactivity of SMRs correlated with different cultivation sites can be a new approach to optimize and utilize the medical materials by chemical and biological aspects of natural macromolecules.
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http://dx.doi.org/10.1016/j.ijbiomac.2020.10.113DOI Listing
December 2020

One-pot microwave-hydrothermally synthesized carbon nanotube-cerium oxide nanocomposites for enhanced visible photodegradation of acid orange 7.

Phys Chem Chem Phys 2020 Oct;22(41):23743-23753

Integrated Composites Laboratory (ICL), Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996, USA.

Carbon nanotubes (CNT)-cerium oxide (CeO2) nanocomposites were fabricated successfully by one-pot microwave hydrothermal growth of regular CeO2 nanoparticles with a size of 8 nm on hydroxyl-functionalized multi-walled CNTs. These nanocomposite photocatalysts demonstrated an acid orange (AO7) photocatalytic degradation efficiency of above 90% under solar-simulated light irradiation for 3 h, which was much higher than that of the pure CeO2 nanoparticles. The enhanced photocatalytic activity was observed to mainly originate from the ˙O2- and hole traps, while the hydroxyl radical ˙OH played a secondary role.
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http://dx.doi.org/10.1039/d0cp00431fDOI Listing
October 2020

The Properties and Preparation Methods of Different Boron Nitride Nanostructures and Applications of Related Nanocomposites.

Chem Rec 2020 Nov 22;20(11):1314-1337. Epub 2020 Sep 22.

Integrated Composites Laboratory (ICL), Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996, USA.

Due to special non-metallic polar bond between the III group (with certain metallic properties) element boron (B) and the V group element nitrogen (N), boron nitride (BN) has unique physical and chemical properties such as strong high-temperature resistance, oxidation resistance, heat conduction, electrical insulation and neutron absorption. Its unique lamellar, reticular and tubular morphologies and physicochemical properties make it attractive in the fields of adsorption, catalysis, hydrogen storage, thermal conduction, insulation, dielectric substrate of electronic devices, radiation protection, polymer composites, medicine, etc. Therefore, the synthesis and properties of BN derived materials become the main research hotspots of low-dimensional nanomaterials. This paper reviews the synthetic methods, overall properties, and applications of BN nanostructures and nanocomposites. In addition, challenges and prospect of this kind of materials are discussed.
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http://dx.doi.org/10.1002/tcr.202000079DOI Listing
November 2020

Constructing CeO/nitrogen-doped carbon quantum dot/g-CN heterojunction photocatalysts for highly efficient visible light photocatalysis.

Nanoscale 2020 Oct 14;12(37):19112-19120. Epub 2020 Sep 14.

Key Laboratory of Bio-based Material Science & Technology (Northeast Forestry University), College of Material Science and Engineering, Ministry of Education, Harbin 150040, China.

Ternary CeO/nitrogen-doped carbon quantum dot (NCQD)/graphitic carbon nitride (g-CN) heterojunction nanocomposites were prepared by a high-temperature calcination and hydrothermal method and tested for degrading tetracycline (TC) and generating H. Compared with CeO and g-CN, the Z-scheme CeO/NCQDs/g-CN (CSNx, where x represents the amount of CeO in wt%) nanoparticles showed a higher TC photodegradation capacity and H evolution ability owing to enhanced efficient charge separation and photocatalytic stability. CSN5 showed the best photodegradation activity for TC degradation (100 mL, 20 mg L; 100% degradation in 60 min; λ≥ 420 nm) and the highest H evolution rate of 1275.42 μmol h g was approximately 3.73- and 32.25-times higher than those of pristine g-CN (341.85 μmol h g) and pure CeO (39.55 μmol h g), respectively. Superoxide (˙O) and hydroxyl (˙OH) radicals were also confirmed to be formed on the sample surface for TC photocatalytic degradation. As an electronic medium, NCQDs transferred electrons between the g-CN and CeO interface to promote the electron-hole separation. This work affords a helpful perspective for synthesizing efficient charge separation and environmentally friendly photocatalysts by controlling the surface heterostructure.
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http://dx.doi.org/10.1039/d0nr02965cDOI Listing
October 2020

Microwave Hydrothermally Synthesized Metal-Organic Framework-5 Derived C-doped ZnO with Enhanced Photocatalytic Degradation of Rhodamine B.

Langmuir 2020 Aug 16;36(33):9658-9667. Epub 2020 Aug 16.

Integrated Composites Laboratory (ICL), Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States.

C-doped ZnO particles have been successfully prepared by the calcination using microwave hydrothermally prepared metal-organic framework-5 (MOF-5) as the precursor. MOF-5 was turned into C-doped ZnO through calcination at 500 °C, and its cubic shape was well-maintained. X-ray photoelectron spectroscopic studies confirmed the C-doping in the ZnO. The as-prepared C-doped ZnO demonstrated a Rhodamine B (RhB) degradation efficiency of 98% in 2 h under an solar-simulated light irradiation, much higher than that of C-doped ZnO derived from MOF-5 synthesized by the ordinary hydrothermal method. The trapping experiment revealed that the crucial factors in the RhB removal were photogenerated h and •O.
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http://dx.doi.org/10.1021/acs.langmuir.0c00395DOI Listing
August 2020

Solvent-free nanoalumina loaded nanocellulose aerogel for efficient oil and organic solvent adsorption.

J Colloid Interface Sci 2021 Jan 23;581(Pt A):299-306. Epub 2020 Jul 23.

Integrated Composites Laboratory (ICL), Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, TN 37966, USA.

Hypothesis: Cellulose-based aerogel, due to its rich reserves, environmental friendliness and porous structure, is considered as a new type of adsorbents for treating oil and water pollution. However, the functionalization of cellulose aerogel is still required for the efficient increase of its adsorption performance in wide applications. The combination of nanomaterials could significantly improve the adsorption capability of nanocellulose aerogel.

Experiments: In this work, nanocomposite aerogels comprising of nanocellulose and nanoalumina (NC/AlO) are produced via a solvent-free method and the effect of weight ratios between nanocellulose and nanoalumina on the adsorption properties of NC/AlO aerogels has been studied.

Findings: The results reveal that the NC/AlO aerogel with a low density of 5.1 mg cm could obtain the optimal pore microstructures and the highest oil and organic solvent adsorption capacities with the preparation condition under the nanocellulose/nanoalumina weight ratio of 1:0.25 and 0.4 wt% of nanocellulose in aqueous solution. The presence of nanoalumina facilitates the change of microstructure morphologies, the increase of BET specific surface area and the adsorption capacities of NC aerogel. Compared with pure NC aerogel (74.07 ± 1.67, 69.87 ± 1.01, 81.21 ± 3.20, 52.07 ± 1.70, 48.49 ± 1.01, 75.45 ± 3.58 and 87.03 ± 0.46 g g for thiophene, anhydrous ethanol, ethyl acetate, cyclohexane, sesame oil, acetone and dichloromethane, respectively), the NC/AlO aerogel manifests an outstanding adsorption capacity (108.07 ± 0.37, 89.91 ± 4.83, 93.93 ± 3.81, 71.13 ± 2.48, 64.83 ± 2.25, 85.19 ± 3.87 and 117.65 ± 5.68 g g, accordingly). By considering the desirable performance features and the convenient fabrication approach, this nanocellulose nanocomposite aerogel might be a feasible alternative for oily waste water recovery and conservation of environment.
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http://dx.doi.org/10.1016/j.jcis.2020.07.099DOI Listing
January 2021

Conductive polyaniline hydrogel enhanced methane production from anaerobic wastewater treatment.

J Colloid Interface Sci 2021 Jan 21;581(Pt A):314-322. Epub 2020 Jul 21.

Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996, United States. Electronic address:

Three-dimensional polyaniline (PANI) hydrogel was used as the conductive medium to improve the methane (CH) production from the anaerobic degradation of organics in wastewater. The porous structure and hydrophilic surface of the PANI hydrogel promoted the adhesion of the anaerobes. The PANI hydrogel existed as a conductive emeraldine base (EB) form with a conductivity of 0.42 S/cm, and had a good biocompatibility with the microorganisms in the anaerobic system. The conductive PANI hydrogel was added into the anaerobic sludge as the conductive medium of the direct interspecies electron transfer (DIET) between bacteria and archaea, accelerating CH production during the biodegradation of organic pollutants. The results indicated that the CH production rate was increased by 10.50%, 14.21%, 28.77% and 19.30% from the anaerobic system with adding 1000, 2000, 3000 and 4000 mg/L of PANI hydrogel. The proportion of Methanosaeta in the anaerobic sludge with the ability of DIET was increased to 64.74% after adding the PANI hydrogel. The conductive PANI hydrogel served as an electronic channel to enrich the microorganism with the DIET ability, which was responsible for PANI hydrogel improved CH production.
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http://dx.doi.org/10.1016/j.jcis.2020.07.075DOI Listing
January 2021

Synthesis of dynamic imine macrocyclic supramolecular polymers via synchronized self-assembly based on dynamic covalent bonds and noncovalent interactions.

Chem Commun (Camb) 2020 Aug;56(65):9288-9291

Integrated Composites Laboratory (ICL), Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996, USA.

The preparation of dynamic imine macrocycles and supramolecular polymers is combined into a single step to form supramolecular polymers (SPs). 1,4-Diazabicyclo[2.2.2]octane (DABCO) derived quaternary ammonium salts induce aldehyde and amine building blocks to covalently form imine macrocycles. Multiple noncovalent interactions between hosts (i.e., imine macrocycle) and guests (i.e., DABCO) act as driving forces. Thus, for the first time, dynamic imine macrocyclic supramolecular polymers (DIMPs) have been achieved through the synchronized self-assembly of dynamic covalent bond formed imine macrocycles and noncovalent interactions of hosts-guests.
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http://dx.doi.org/10.1039/d0cc02991bDOI Listing
August 2020

Overview of Ionogels in Flexible Electronics.

Chem Rec 2020 Sep 13;20(9):948-967. Epub 2020 Jul 13.

Integrated Composites Laboratory (ICL), Department of Chemical Engineering, University of Tennessee, Knoxville, TN, 37996, USA.

Ionogels have aroused wide interests in the field of flexible electronics. The combination of solid-state networks and ionic liquids opens up thousands of possibilities for ionogels. The unique structures of ionogels endow them excellent mechanical properties, conductivity and thermal stability to approach the challenge of flexible electronic. A large number of new ionogels have been developed by different methods including the exchange of solution, polymeric ionic liquid and in-situ reactions in ionic liquids (gelation of low molecular weight gelators, self-assembly of block polymers, formation of double-network structure, ionogel nanocomposites and direct polymerization of polymerizable monomers). The aim of this review is to discuss different preparation methods of ionogels and the comparison of their advantages.
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http://dx.doi.org/10.1002/tcr.202000041DOI Listing
September 2020

Binder-free CuS/ZnS/sodium alginate/rGO nanocomposite hydrogel electrodes for enhanced performance supercapacitors.

Int J Biol Macromol 2020 Nov 20;162:310-319. Epub 2020 Jun 20.

Key Laboratory of Materials Processing and Mold, Ministry of Education, National Engineering Research Center for Advanced Polymer Processing Technology, Zhengzhou University, Zhengzhou, China. Electronic address:

CuS/ZnS/sodium alginate/reduced graphene oxide nanocomposites (CZSrG) were prepared by physical crosslinking followed by one-step reduction and were justified as green binder-free hydrogel high-capacitance electrodes. The physical crosslinking was realized simply through the hydrogen-bond interaction between sodium alginate (SA) and graphene oxide (GO), avoiding the usage of traditional Ca crosslinking agent. The hydrogel structure made of CZSrG possessed the most beneficial effect of avoiding large volume change and increasing cycle stability for supercapacitors. When used as electrode, the specific capacitance of CZSrG was 992 F·g (10 mV·s) in a three-electrode system. Furthermore, the fabricated supercapacitors had a specific capacitance of 252.1 F·g (5 mV·s), and a power density of 1800 Wh·kg at the energy density of 2.05 Wh·kg. Thus, the CZSrG has a favorable electrochemical performance and wide application prospects in supercapacitors.
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http://dx.doi.org/10.1016/j.ijbiomac.2020.06.169DOI Listing
November 2020

Cu/N doped lignin for highly selective efficient removal of As(v) from polluted water.

Int J Biol Macromol 2020 Oct 5;161:147-154. Epub 2020 Jun 5.

Integrated Composites Laboratory (ICL), Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville 17996, USA. Electronic address:

Lignin is a widely used adsorbent for removing heavy metal ions from water. Lignin can be extracted from black liquor and its inert surface properties limit its adsorption performance. In this paper, a new type of modified lignin adsorbent doped with Cu/N was prepared by the reaction of lignin with triethylenetetramine (TETA) and CuCl. The adsorption capacities of the Cu/N-doped lignin (Cu/N-Lignin) adsorbents, N-doped lignin (N-Lignin) adsorbents and undoped lignin (U-Lignin) on three anions (As (V), Cl and Cr (VI)) were systematically studied. In the solution with these three mixed ions, the removal rate of the Cu/N-Lignin adsorbents on As (V), Cl and Cr (VI) was 86.44%, 0% and 39.48%. The adsorption capacity of Cu/N-Lignin to As(V) was 253.5 mg/g. Under the same adsorption conditions, the selectivity of the Cu/N-Lignin adsorbents to anions was Cl
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http://dx.doi.org/10.1016/j.ijbiomac.2020.06.016DOI Listing
October 2020

An inverse opal CuNbO anode for high-performance Li storage.

Chem Commun (Camb) 2020 Jul 1;56(53):7321-7324. Epub 2020 Jun 1.

Institute of Materials for Energy and Environment, School of Materials Science and Engineering, Qingdao University, Qingdao 266071, China.

CuNbO with an inverse opal morphology is fabricated, showing highly-ordered macropores with sizes of ∼170 nm and walls with thicknesses of 20-30 nm. This first-reported CuNbO nanomaterial exhibits good Li-storage properties, including a large capacity, safe operating potential, large initial coulombic efficiency, high rate performance and good cycling stability.
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http://dx.doi.org/10.1039/d0cc02016hDOI Listing
July 2020

Controllable antibacterial and bacterially anti-adhesive surface fabricated by a bio-inspired beetle-like macromolecule.

Int J Biol Macromol 2020 Aug 28;157:553-560. Epub 2020 Apr 28.

Integrated Composites Laboratory (ICL), Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996, USA.

Drug resistance to bacteria becomes an emerging intractable problem, therefore, developing novel antibacterial agents has become urgently needed. Herein, a bio-inspired design strategy was adopted to synthesize a series of beetle-like macromolecule of multiple quaternary ammonium salts (QASs), which was designed with different cationic charge densities and numbers of hexadecane chains by adjusting their different quaternization degree (QD). It was found that the fabricated fabric surface with them exhibited controllable and outstanding antibacterial and bacterially anti-adhesive properties. More importantly, the antibacterial efficiency was demonstrated to be enhanced with the increasing of QD, and related to the zeta potential, and surface tension. Additionally, the proposed bacterially anti-adhesive model of action revealed the "resisting effect" of hydration layer which greatly resisted the adhesion of bacteria.
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http://dx.doi.org/10.1016/j.ijbiomac.2020.04.207DOI Listing
August 2020

Fast room-temperature self-healing siloxane elastomer for healable stretchable electronics.

J Colloid Interface Sci 2020 Aug 1;573:105-114. Epub 2020 Apr 1.

MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China.

Siloxane elastomers having simultaneously high stretchability, fast and efficient self-healing abilities at room temperature and excellent mechanical properties have broad application prospects in many fields. However, it is still challenging to satisfy this request. In this work, a stretchable, fast self-healing siloxane elastomer was successfully synthesized by introducing aromatic disulfides into a siloxane matrix. The resulting siloxane elastomer exhibited a tensile stress of 0.5 MPa, an elongation at break over 1000%, and a healing efficiency above 95% at room temperature. The healed siloxane elastomer could recover an elongation at break of 357 ± 15% after healing for only one minute at room temperature. A healing efficiency higher than 90% was achieved even after surface aging or by overlap contact, which was due to the presence of the dynamic disulfide bonds. Furthermore, the elastomer was successfully deployed as the substrate for self-healing stretchable electronics. As a proof-of-concept, stretchable electrode and stretchable strain sensors were produced, and they all showed high stretchability, fast self-healing properties at room temperature and high durability and stability, paving the way to promising applications in stretchable and wearable electronics.
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http://dx.doi.org/10.1016/j.jcis.2020.03.125DOI Listing
August 2020

Overview of Polyvinyl Alcohol Nanocomposite Hydrogels for Electro-Skin, Actuator, Supercapacitor and Fuel Cell.

Chem Rec 2020 Aug 10;20(8):773-792. Epub 2020 Mar 10.

Integrated Composites Laboratory (ICL), Department of Chemical Engineering, University of Tennessee, Knoxville, TN 37996, USA.

The properties of polyvinyl alcohol (PVA) nanocomposite hydrogels influenced by nanoparticles are reviewed. Various kinds of nanoparticles with excellent mechanical and electrical properties have been introduced into PVA hydrogel to produce stretchable and conductive PVA nanocomposite hydrogel. Understanding the mechanism between the matrix of PVA hydrogel and nanoparticles is therefore critical for the development of PVA nanocomposite hydrogels. This review focuses on the nanoparticles include carbon nanotubes, graphene oxide and metal nanoparticles, and describes the effects of nanoparticles on the mechanical and conductive properties of PVA nanocomposite hydrogels. A new promising area of soft stretchable PVA nanocomposite hydrogel is highlighted for possible applications. Finally, a brief outlook for future research is presented.
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http://dx.doi.org/10.1002/tcr.202000001DOI Listing
August 2020

Enteromorpha prolifera polysaccharide based coagulant aid for humic acids removal and ultrafiltration membrane fouling control.

Int J Biol Macromol 2020 Jun 24;152:576-583. Epub 2020 Feb 24.

Integrated Composites Lab (ICL), Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996, USA. Electronic address:

Polyacrylamide (PAM) has been used as a coagulant aid in water treatment process for past decades, but it has caused great damages to human nervous system. Developing new coagulant aid with high biological safety is urgently demanded. This study provides a natural biomacromolecule coagulant aid with good biosecurity-Enteromorpha prolifera polysaccharide (Ep). Its coagulant aid efficiency and mechanism were investigated in terms of organics removal, floc properties and membrane fouling degree. In addition, contrast experiments were conducted with PAM to evaluate its potential of industrial applications. Results showed that organics removal could be increased by 23% when 0.3 mg/L Ep was used, which exhibited comparable aid effects to PAM. Due to the bridging-sweep aid role of Ep, flocs sizes, growth rate and recovery factor reached 470 μm, 62.6 μm/min and 0.492, respectively, while only 170 μm, 14.0 μm/min and 0.326 were obtained by PAM. Additionally, flocs exhibited more porous and multi-branched structures when Ep was applied, which caused less ultrafiltration membrane fouling (eventual J/J value = 0.52). As a result, Ep could be considered as a potential substitute of PAM, since better biosecurity, higher organics removal and lower membrane fouling could be obtained simultaneously by Ep addition.
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http://dx.doi.org/10.1016/j.ijbiomac.2020.02.273DOI Listing
June 2020

Boosting Multiple Interfaces by Co-Doped Graphene Quantum Dots for High Efficiency and Durability Perovskite Solar Cells.

ACS Appl Mater Interfaces 2020 Mar 16;12(12):13941-13949. Epub 2020 Mar 16.

State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, China.

Organic-inorganic hybrid perovskite solar cells (PSCs), as the most rapidly developing next-generation thin-film photovoltaic technology, have attracted extensive research interest, yet their efficiency, scalability, and durability remain challenging. α-FeO could be used as an electron transporting layer (ETL) of planar PSCs, which exhibits a much higher humidity and UV light-stability compared to TiO-based planar PSCs. However, the photovoltaic conversion efficiency (PCE) of the FeO-based device was still below 15% because of poor interface contact between α-FeO and perovskite and poor crystal quality of perovskites. In this work, we have engineered the interfaces throughout the entire solar cell incorporating N, S co-doped graphene quantum dots (NSGQDs). The NSGQDs played remarkable multifunctional roles: (i) facilitated the perovskite crystal growth; (ii) eased charge extraction at both anode and cathode interfaces; and (iii) induced the defect passivation and suppressed the charge recombination. When assembled with a α-FeO ETL, the planar PSCs exhibited a significantly increased efficiency from 14 to 19.2%, with concomitant reductions in hysteresis, which created a new record of the PCE for FeO-based PSCs to date. In addition, PSCs with the entire device interfacial engineering showed an obviously improved durability, including prominent humidity, UV light, and thermal stabilities. Our interfacial engineering methodology graphene quantum dots represents a versatile and effective way for building high efficiency as well as durable PSCs.
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http://dx.doi.org/10.1021/acsami.9b23255DOI Listing
March 2020

Flexible silver nanowire/carbon fiber felt metacomposites with weakly negative permittivity behavior.

Phys Chem Chem Phys 2020 Mar 19;22(9):5114-5122. Epub 2020 Feb 19.

College of Ocean Science and Engineering, Shanghai Maritime University, Shanghai 201306, China.

Recently, flexible metacomposites with negative permittivity have triggered extensive interest owing largely to their promising applications in areas such as sensors, cloaking, and wearable and flexible electronic devices. In this paper, flexible silver nanowire/carbon fiber felt (AgNW/CFF) metacomposites with weakly negative permittivity were fabricated by adjusting their composition and microstructure. Along with the formation of a conductive AgNW network, the resulting composites gradually presented metal-like behavior. Interestingly, weakly negative permittivity with a small absolute value (as low as about 6.4) and good flexibility were observed in the composites with 3.7 wt% AgNWs. The one-dimensional silver nanowires contribute to reducing the overall electron density of the resulting composites, which is responsible for the weakly negative permittivity. As the AgNWs increased, the Drude-like negative permittivity got stronger owing to the enhancement of the electron density. Further investigation from the perspective of microelectronics revealed that the negative permittivity is dependent on the inductive characteristic. The proposed design strategy for AgNW/CFF composites with tunable negative permittivity opens up a new approach to flexible metacomposites.
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http://dx.doi.org/10.1039/c9cp06196gDOI Listing
March 2020

Low optical dosage heating-reduced viscosity for fast and large-scale cleanup of spilled crude oil by reduced graphene oxide melamine nanocomposite adsorbents.

Nanotechnology 2020 May 17;31(22):225402. Epub 2020 Feb 17.

Research Center of Resource Recycling Science and Engineering, School of Environmental and Materials Engineering, Shanghai Polytechnic University, Shanghai 201209, People's Republic of China.

Heating under low solar radiation intensity is demonstrated to facilitate the cleaning of crude oil by the hydrophobic nanocomposite adsorbents of reduced graphene oxide (RGO) melamine sponge (MS@RGO) foams. The heat generated by the irradiation reduces the viscosity of the crude oil, and consequently increases the oil-diffusion coefficient of the pores of the MS@RGO foams and speeds up the oil-sorption rate. Even under a solar radiation intensity as low as 2 kW m, the temperature of crude oil rapidly rises to 68 °C or higher within 10 min. It only takes 29 s to completely absorb 6 g of crude oil at 60 °C by three tiny pieces of MS@RGO foam. This work makes better use of the excellent photothermal conversion characteristics of crude oil, and its photothermal conversion mechanism under simulated solar radiation is also discussed. This methodology can be adopted to clean up viscous crude oil or extract other chemicals effectively at a large scale, and provides a complete solution for the cleanup of crude oil in the sea or on the beach for actual engineering applications.
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http://dx.doi.org/10.1088/1361-6528/ab76ebDOI Listing
May 2020

Sodium-ion capacitors: Materials, Mechanism, and Challenges.

ChemSusChem 2020 May 24;13(10):2522-2539. Epub 2020 Mar 24.

Integrated Composites Laboratory, Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN, 37996, USA.

Sodium-ion capacitors (SICs), designed to attain high energy density, rapid energy delivery, and long lifespan, have attracted much attention because of their comparable performance to lithium-ion capacitors (LICs), alongside abundant sodium resources. Conventional SIC design is based on battery-like anodes and capacitive cathodes, in which the battery-like anode materials involve various reactions, such as insertion, alloying, and conversion reactions, and the capacitive cathode materials usually depend on activated carbon (AC). However, researchers have attempted to construct SICs based on battery-like cathodes and capacitive anodes or a combination of both in recent years. In this Minireview, charge storage mechanisms and material design strategies for SICs are summarized, with a focus on the battery-like anode materials from both inorganic and organic sources. Additionally, the challenges in the fabrication of SICs and future research directions are discussed.
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http://dx.doi.org/10.1002/cssc.201903440DOI Listing
May 2020

Laccase immobilized polyaniline/magnetic graphene composite electrode for detecting hydroquinone.

Int J Biol Macromol 2020 Apr 27;149:1130-1138. Epub 2020 Jan 27.

Integrated Composites Lab (ICL), Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996, USA. Electronic address:

Magnetic graphene nanocomposites were prepared by hydrothermal synthesis, and aniline polymerization was initiated by magnetic graphene. These polyaniline/magnetic graphene (PANI/MG) composites were used to immobilize laccase to construct biosensors. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and infrared spectroscopy (IR) were used to characterize these composites. Cyclic voltammetry and chronoamperometry technique were used to test the electrical properties of the constructed polyaniline/magnetic graphene laccase modified electrode. The results show that the polyaniline/magnetic graphene immobilizing laccase modified electrode exhibited superior electrical properties, including high sensitivity, detection limit and linear range. The hydroquinone was used as an analytical and detection probe. The selectivity was 0.03639 A/(mol/L), the linear range was 0.4-337.2 μmol/L, and the detection limit was 2.94 μM (signal/noise = 3, minimum identification value of effective signal). The biosensor can reach the conditions for detecting the actual water sample.
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http://dx.doi.org/10.1016/j.ijbiomac.2020.01.248DOI Listing
April 2020

N self-doped ZnO derived from microwave hydrothermal synthesized zeolitic imidazolate framework-8 toward enhanced photocatalytic degradation of methylene blue.

J Colloid Interface Sci 2020 Apr 26;565:142-155. Epub 2019 Dec 26.

Integrated Composites Laboratory (ICL), Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, TN 37996, USA. Electronic address:

The precursor particles were successfully prepared by a facile microwave hydrothermal method. Compared with solvothermal and precipitation method, microwave hydrothermal method can greatly shorten the reaction time and increase the product yields. Nitrogen (N) doped zinc oxide (ZnO) nanoparticles were derived via one-step controllable pyrolysis of zeolitic imidazolate framework-8 (Zif-8) precursors under 550 °C. The powder X-ray diffraction (XRD) analysis, elemental mapping image, energy dispersive spectrometry (EDS) spectra and X-ray photoelectron spectroscopy (XPS) analysis proved that Zif-8 particles were converted to ZnO and the N atoms were successfully doped into ZnO lattice. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results demonstrated that N doped ZnO retained the morphology of Zif-8 with a particle size of approximately ~70 nm and the UV-visible diffuse reflectance spectra (UV-vis DRS) showed that the as-prepared N doped ZnO possessed a lower band gap (3.16 eV) than commercial ZnO (3.26 eV). The photocatalytic activities of the as-prepared samples were evaluated by the degradation rate of methylene blue (MB) upon irradiation with solar-simulated light. The photocatalytic degradation efficiency of N doped ZnO was 95.3% after 80 min illumination, which was much higher than that of other samples prepared by other methods. Quenching tests proved that the photo-generated holes (h) played a main role in the photodegradation of MB under solar-simulated light irradiation.
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http://dx.doi.org/10.1016/j.jcis.2019.12.107DOI Listing
April 2020