Publications by authors named "Jiaqi Dai"

94 Publications

Stamping Flexible Li Alloy Anodes.

Adv Mater 2021 Mar 10;33(11):e2005305. Epub 2021 Feb 10.

Department of Materials Science and Engineering, University of Maryland, College Park, MD, 20742, USA.

Li metal holds great promise to be the ultimate anode choice owing to its high specific capacity and low redox potential. However, processing Li metal into thin-film anode with high electrochemical performance and good safety to match commercial cathodes remains challenging. Herein, a new method is reported to prepare ultrathin, flexible, and high-performance Li-Sn alloy anodes with various shapes on a number of substrates by directly stamping a molten metal solution. The printed anode is as thin as 15 µm, corresponding to an areal capacity of ≈3 mAh cm that matches most commercial cathode materials. The incorporation of Sn provides the nucleation center for Li, thereby mitigating Li dendrites as well as decreasing the overpotential during Li stripping/plating (e.g., <10 mV at 0.25 mA cm ). As a proof-of-concept, a flexible Li-ion battery using the ultrathin Li-Sn alloy anode and a commercial NMC cathode demonstrates good electrochemical performance and reliable cell operation even after repetitive deformation. The approach can be extended to other metal/alloy anodes such as Na, K, and Mg. This study opens a new door toward the future development of high-performance ultrathin alloy-based anodes for next-generation batteries.
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http://dx.doi.org/10.1002/adma.202005305DOI Listing
March 2021

Developing fibrillated cellulose as a sustainable technological material.

Nature 2021 02 3;590(7844):47-56. Epub 2021 Feb 3.

Department of Materials Science and Engineering, University of Maryland, College Park, MD, USA.

Cellulose is the most abundant biopolymer on Earth, found in trees, waste from agricultural crops and other biomass. The fibres that comprise cellulose can be broken down into building blocks, known as fibrillated cellulose, of varying, controllable dimensions that extend to the nanoscale. Fibrillated cellulose is harvested from renewable resources, so its sustainability potential combined with its other functional properties (mechanical, optical, thermal and fluidic, for example) gives this nanomaterial unique technological appeal. Here we explore the use of fibrillated cellulose in the fabrication of materials ranging from composites and macrofibres, to thin films, porous membranes and gels. We discuss research directions for the practical exploitation of these structures and the remaining challenges to overcome before fibrillated cellulose materials can reach their full potential. Finally, we highlight some key issues towards successful manufacturing scale-up of this family of materials.
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http://dx.doi.org/10.1038/s41586-020-03167-7DOI Listing
February 2021

Printable, high-performance solid-state electrolyte films.

Sci Adv 2020 Nov 18;6(47). Epub 2020 Nov 18.

Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA.

Current ceramic solid-state electrolyte (SSE) films have low ionic conductivities (10 to 10 S/cm ), attributed to the amorphous structure or volatile Li loss. Herein, we report a solution-based printing process followed by rapid (~3 s) high-temperature (~1500°C) reactive sintering for the fabrication of high-performance ceramic SSE films. The SSEs exhibit a dense, uniform structure and a superior ionic conductivity of up to 1 mS/cm. Furthermore, the fabrication time from precursor to final product is typically ~5 min, 10 to 100 times faster than conventional SSE syntheses. This printing and rapid sintering process also allows the layer-by-layer fabrication of multilayer structures without cross-contamination. As a proof of concept, we demonstrate a printed solid-state battery with conformal interfaces and excellent cycling stability. Our technique can be readily extended to other thin-film SSEs, which open previously unexplores opportunities in developing safe, high-performance solid-state batteries and other thin-film devices.
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http://dx.doi.org/10.1126/sciadv.abc8641DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7673806PMC
November 2020

Monochromatic Blue Light Activates Suprachiasmatic Nucleus Neuronal Activity and Promotes Arousal in Mice Under Sevoflurane Anesthesia.

Front Neural Circuits 2020 18;14:55. Epub 2020 Aug 18.

Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

: Monochromatic blue light (MBL), with a wavelength between 400-490 nm, can regulate non-image-forming (NIF) functions of light in the central nervous system. The suprachiasmatic nucleus (SCN) in the brain is involved in the arousal-promoting response to blue light in mice. Animal and human studies showed that the responsiveness of the brain to visual stimuli is partly preserved under general anesthesia. Therefore, this study aimed to investigate whether MBL promotes arousal from sevoflurane anesthesia activation of the SCN in mice. : The induction and emergence time of sevoflurane anesthesia under MBL (460 nm and 800 lux) exposure was measured. Cortical electroencephalograms (EEGs) were recorded and the burst-suppression ratio (BSR) was calculated under MBL during sevoflurane anesthesia. The EEGs and local field potential (LFP) recordings with or without locally electrolytic ablated bilateral SCN were used to further explore the role of SCN in the arousal-promoting effect of MBL under sevoflurane anesthesia. Immunofluorescent staining of c-Fos was conducted to reveal the possible downstream mechanism of SCN activation. : Unlike the lack of effect on the induction time, MBL shortened the emergence time and the EEG recordings showed cortical arousal during the recovery period. MBL resulted in a significant decrease in BSR and a marked increase in EEG power at all frequency bands except for the spindle band during 2.5% sevoflurane anesthesia. MBL exposure under sevoflurane anesthesia enhances the neuronal activity of the SCN. These responses to MBL were abolished in SCN lesioned (SCNx) mice. MBL evoked a high level of c-Fos expression in the prefrontal cortex (PFC) and lateral hypothalamus (LH) compared to polychromatic white light (PWL) under sevoflurane anesthesia, while it exerted no effect on c-Fos expression in the ventrolateral preoptic area (VLPO) and locus coeruleus (LC) c-Fos expression. : MBL promotes behavioral and electroencephalographic arousal from sevoflurane anesthesia the activation of the SCN and its associated downstream wake-related nuclei. The clinical implications of this study warrant further study.
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http://dx.doi.org/10.3389/fncir.2020.00055DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7461971PMC
August 2020

TMT-labeling Proteomics of Papillary Thyroid Carcinoma Reveal Invasive Biomarkers.

J Cancer 2020 25;11(20):6122-6132. Epub 2020 Aug 25.

Shanghai Research Center for Thyroid Diseases, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, 200072, P. R. China.

Invasion and metastasis are critical events in papillary thyroid carcinoma (PTC) progression. Protein markers specific to this process may avoid over-treatment and urgently needed. TMT-labeled mass spectrometry-based proteomics were carried out on PTC and invasive phenotype (iPTC) (3 pairs per group) and cross validate differentially expressed proteins (DEPs) (FC>1.5 and <0.67 and p<0.05) with GEO and TCGA datasets and the correlation genes of DEPs were also analyzed. We identified and quantified 4607 proteins identical to PTC and iPTC groups. Among which 12 DEPs in PTC and 179 DEPs in iPTCs were found. Cross-validation with GSE60542 and TCGA database revealed 10 DEPs that all significant correlated with metastasis and staging. Upregulated SLC27A6 showed negative correlation with 6 out of 9 downregulated DEPs including HGD, CA4, COL23A1, SLC26A7, FHL1 and TPO. The panel of 7 genes (SLC27A6 and 6 downregulated DEPs) could have ideal prediction value to improve our understanding of invasiveness of PTC.
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http://dx.doi.org/10.7150/jca.47290DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7477402PMC
August 2020

Scalable aesthetic transparent wood for energy efficient buildings.

Nat Commun 2020 07 31;11(1):3836. Epub 2020 Jul 31.

Department of Materials Science and Engineering, University of Maryland, College Park, MD, 20742, USA.

Nowadays, energy-saving building materials are important for reducing indoor energy consumption by enabling better thermal insulation, promoting effective sunlight harvesting and offering comfortable indoor lighting. Here, we demonstrate a novel scalable aesthetic transparent wood (called aesthetic wood hereafter) with combined aesthetic features (e.g. intact wood patterns), excellent optical properties (an average transmittance of ~ 80% and a haze of ~ 93%), good UV-blocking ability, and low thermal conductivity (0.24 W mK) based on a process of spatially selective delignification and epoxy infiltration. Moreover, the rapid fabrication process and mechanical robustness (a high longitudinal tensile strength of 91.95 MPa and toughness of 2.73 MJ m) of the aesthetic wood facilitate good scale-up capability (320 mm × 170 mm × 0.6 mm) while saving large amounts of time and energy. The aesthetic wood holds great potential in energy-efficient building applications, such as glass ceilings, rooftops, transparent decorations, and indoor panels.
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http://dx.doi.org/10.1038/s41467-020-17513-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7395769PMC
July 2020

Overcoming immiscibility toward bimetallic catalyst library.

Sci Adv 2020 Apr 24;6(17):eaaz6844. Epub 2020 Apr 24.

Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA.

Bimetallics are emerging as important materials that often exhibit distinct chemical properties from monometallics. However, there is limited access to homogeneously alloyed bimetallics because of the thermodynamic immiscibility of the constituent elements. Overcoming the inherent immiscibility in bimetallic systems would create a bimetallic library with unique properties. Here, we present a nonequilibrium synthesis strategy to address the immiscibility challenge in bimetallics. As a proof of concept, we synthesize a broad range of homogeneously alloyed Cu-based bimetallic nanoparticles regardless of the thermodynamic immiscibility. The nonequilibrated bimetallic nanoparticles are further investigated as electrocatalysts for carbon monoxide reduction at commercially relevant current densities (>100 mA cm), in which CuNi shows the highest multicarbon product Faradaic efficiency of ~76% with a current density of ~93 mA cm. The ability to overcome thermodynamic immiscibility in multimetallic synthesis offers freedom to design and synthesize new functional nanomaterials with desired chemical compositions and catalytic properties.
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http://dx.doi.org/10.1126/sciadv.aaz6844DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7182425PMC
April 2020

A general method to synthesize and sinter bulk ceramics in seconds.

Science 2020 05;368(6490):521-526

Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA.

Ceramics are an important class of materials with widespread applications because of their high thermal, mechanical, and chemical stability. Computational predictions based on first principles methods can be a valuable tool in accelerating materials discovery to develop improved ceramics. It is essential to experimentally confirm the material properties of such predictions. However, materials screening rates are limited by the long processing times and the poor compositional control from volatile element loss in conventional ceramic sintering techniques. To overcome these limitations, we developed an ultrafast high-temperature sintering (UHS) process for the fabrication of ceramic materials by radiative heating under an inert atmosphere. We provide several examples of the UHS process to demonstrate its potential utility and applications, including advancements in solid-state electrolytes, multicomponent structures, and high-throughput materials screening.
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http://dx.doi.org/10.1126/science.aaz7681DOI Listing
May 2020

Rapid Processing of Whole Bamboo with Exposed, Aligned Nanofibrils toward a High-Performance Structural Material.

ACS Nano 2020 05 17;14(5):5194-5202. Epub 2020 Apr 17.

Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States.

Lightweight structural materials are critical in construction and automobile applications. In past centuries, there has been great success in developing strong structural materials, such as steels, concrete, and petroleum-based composites, most of which, however, are either too heavy, high cost, or nonrenewable. Biosourced composites are attractive alternatives to conventional structural materials, especially when high mechanical strength is presented. Here we demonstrate a strong, lightweight bio-based structural material derived from bamboo a two-step manufacturing process involving partial delignification followed by microwave heating. Partial delignification is a critical step prior to microwave heating as it makes the cell walls of bamboo softer and exposes more cellulose nanofibrils, which enables superior densification of the bamboo structure heat-driven shrinkage. Additionally, microwave heating, as a fast and uniform heating method, can drive water out of the bamboo structure, yet without destroying the material's structural integrity, even after undergoing a large volume reduction of 28.9%. The resulting microwave-heated delignified bamboo structure demonstrates outstanding mechanical properties with a nearly 2-times improved tensile strength, 3.2-times enhanced toughness, and 2-times increased bending strength compared to natural bamboo. Additionally, the specific tensile strength of the modified bamboo structure reaches 560 MPa cm g, impressive given that its density is low (1.0 g cm), outperforming common structural materials, such as steels, metal alloys, and petroleum-based composites. These excellent mechanical properties combined with the resource abundance, renewable and sustainable features of bamboo, as well as the rapid, scalable manufacturing process, make this strong microwave-processed bamboo structure attractive for lightweight, energy-efficient engineering applications.
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http://dx.doi.org/10.1021/acsnano.9b08747DOI Listing
May 2020

High-throughput, combinatorial synthesis of multimetallic nanoclusters.

Proc Natl Acad Sci U S A 2020 03 10;117(12):6316-6322. Epub 2020 Mar 10.

Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742;

Multimetallic nanoclusters (MMNCs) offer unique and tailorable surface chemistries that hold great potential for numerous catalytic applications. The efficient exploration of this vast chemical space necessitates an accelerated discovery pipeline that supersedes traditional "trial-and-error" experimentation while guaranteeing uniform microstructures despite compositional complexity. Herein, we report the high-throughput synthesis of an extensive series of ultrafine and homogeneous alloy MMNCs, achieved by 1) a flexible compositional design by formulation in the precursor solution phase and 2) the ultrafast synthesis of alloy MMNCs using thermal shock heating (i.e., ∼1,650 K, ∼500 ms). This approach is remarkably facile and easily accessible compared to conventional vapor-phase deposition, and the particle size and structural uniformity enable comparative studies across compositionally different MMNCs. Rapid electrochemical screening is demonstrated by using a scanning droplet cell, enabling us to discover two promising electrocatalysts, which we subsequently validated using a rotating disk setup. This demonstrated high-throughput material discovery pipeline presents a paradigm for facile and accelerated exploration of MMNCs for a broad range of applications.
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http://dx.doi.org/10.1073/pnas.1903721117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7104385PMC
March 2020

A Strong, Tough, and Scalable Structural Material from Fast-Growing Bamboo.

Adv Mater 2020 Mar 30;32(10):e1906308. Epub 2020 Jan 30.

Department of Materials Science and Engineering, University of Maryland, College Park, MD, 20742, USA.

Lightweight structural materials with high strength are desirable for advanced applications in transportation, construction, automotive, and aerospace. Bamboo is one of the fastest growing plants with a peak growth rate up to 100 cm per day. Here, a simple and effective top-down approach is designed for processing natural bamboo into a lightweight yet strong bulk structural material with a record high tensile strength of ≈1 GPa and toughness of 9.74 MJ m . More specifically, bamboo is densified by the partial removal of its lignin and hemicellulose, followed by hot-pressing. Long, aligned cellulose nanofibrils with dramatically increased hydrogen bonds and largely reduced structural defects in the densified bamboo structure contribute to its high mechanical tensile strength, flexural strength, and toughness. The low density of lignocellulose in the densified bamboo leads to a specific strength of 777 MPa cm g , which is significantly greater than other reported bamboo materials and most structural materials (e.g., natural polymers, plastics, steels, and alloys). This work demonstrates a potential large-scale production of lightweight, strong bulk structural materials from abundant, fast-growing, and sustainable bamboo.
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http://dx.doi.org/10.1002/adma.201906308DOI Listing
March 2020

Single-digit-micrometer thickness wood speaker.

Nat Commun 2019 11 8;10(1):5084. Epub 2019 Nov 8.

Department of Materials Science and Engineering, University of Maryland, College Park, MD, 20742, USA.

Thin films of several microns in thickness are ubiquitously used in packaging, electronics, and acoustic sensors. Here we demonstrate that natural wood can be directly converted into an ultrathin film with a record-small thickness of less than 10 μm through partial delignification followed by densification. Benefiting from this aligned and laminated structure, the ultrathin wood film exhibits excellent mechanical properties with a high tensile strength of 342 MPa and a Young's modulus of 43.6 GPa, respectively. The material's ultrathin thickness and exceptional mechanical strength enable excellent acoustic properties with a 1.83-times higher resonance frequency and a 1.25-times greater displacement amplitude than a commercial polypropylene diaphragm found in an audio speaker. As a proof-of-concept, we directly use the ultrathin wood film as a diaphragm in a real speaker that can output music. The ultrathin wood film with excellent mechanical property and acoustic performance is a promising candidate for next-generation acoustic speakers.
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http://dx.doi.org/10.1038/s41467-019-13053-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6841728PMC
November 2019

Decoupling Ionic and Electronic Pathways in Low-Dimensional Hybrid Conductors.

J Am Chem Soc 2019 Nov 24;141(44):17830-17837. Epub 2019 Oct 24.

Department of Materials Science and Engineering , University of Maryland , College Park , Maryland 20742 , United States.

The construction of two-dimensional (2D) layered compounds for nanofluidic ion transport has recently attracted increasing interest due to the facile fabrication, tunable channel size, and high flux of these materials. Here we design a nacre-mimetic graphite-based nanofluidic structure in which the nanometer-thick graphite flakes are wrapped by negatively charged nanofibrillated cellulose (NFC) fibers to form multiple 2D confined spacings as nanochannels for rapid cation transport. At the same time, the graphite-NFC structure exhibits an ultralow electrical conductivity (σ ≤ 10 S/cm), even when the graphite concentration is up to 50 wt %, well above the percolation threshold (∼1 wt %). By tuning the hydration degree of graphite-NFC composites, the surface-charge-governed ion transport in the confined ∼1 nm spacings exhibits nearly 12 times higher ionic conductivity (1 × 10 S/cm) than that of a fully swollen structure (∼1.5 nm, 8.5 × 10 S/cm) at salt concentrations up to 0.1 M. The resulting charge selective conductor shows intriguing features of both high ionic conductivity and low electrical conductivity. Moreover, the inherent stability of the graphite and NFC components contributes to the strong functionality of the nanofluidic ion conductors in both acidic and basic environments. Our work demonstrates this 1D-2D material hybrid system as a suitable platform to study nanofluidic ion transport and provides a promising strategy to decouple ionic and electronic pathways, which is attractive for applications in new nanofluidic device designs.
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http://dx.doi.org/10.1021/jacs.9b09009DOI Listing
November 2019

Consideration of Age Is Necessary for Increasing the Accuracy of the AJCC TNM Staging System of Pancreatic Neuroendocrine Tumors.

Front Oncol 2019 19;9:906. Epub 2019 Sep 19.

Thyroid Center, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.

Currently, of the two most common staging systems of pancreatic neuroendocrine tumors (pNETs) one is from the European Neuroendocrine Tumor Society (ENETS) and the other is from the American Joint Committee on Cancer (AJCC). However, there are imperfections in both these staging systems. Patients were selected retrospectively from the Surveillance Epidemiology and End Results (SEER) database (2004 to 2013). The effect of age on the hazard ratio (HR) was evaluated using restricted cubic splines. The discriminatory power of the staging systems was determined using the concordance index (C-index). A total of 3,034 patients with pNETs were included in the final analyses. The risk of death increased slowly along with age for patients under 60 years of age, but the risk of death rose sharply for those over 60 years of age, forming a mirrored L-shaped survival curve. In the current AJCC tumor-node-metastasis (TNM) staging system, no statistical significance was observed between stages IA and IB ( = 0.105). Patients with stage IIB even had longer OS than patients with IIA, although there was no statistical significance ( = 0.574). The proportion of stage III patients was small (2.7%). In the proposed aTNM staging system, significant survival differences could be observed among stage I, IIA, and IIB ( < 0.001) and the proportion of stage III rose from 2.7 to 25.7%. Our findings suggest that age has a critical influence on the survival of patients with pNETs. Age should be considered as a factor in future staging systems of pNETs.
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http://dx.doi.org/10.3389/fonc.2019.00906DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6761294PMC
September 2019

Catalyst-Free Carbon Nanotube Growth in Confined Space High Temperature Gradient.

Research (Wash D C) 2018 10;2018:1793784. Epub 2018 Dec 10.

Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA.

Carbonaceous materials, such as graphite, carbon nanotubes (CNTs), and graphene, are in high demand for a broad range of applications, including batteries, capacitors, and composite materials. Studies on the transformation between different types of carbon, especially from abundant and low-cost carbon to high-end carbon allotropes, have received surging interest. Here, we report that, without a catalyst or an external carbon source, biomass-derived amorphous carbon and defective reduced graphene oxide (RGO) can be quickly transformed into CNTs in highly confined spaces by high temperature Joule heating. Combined with experimental measurements and molecular dynamics simulations, we propose that Joule heating induces a high local temperature at defect sites due to the corresponding high local resistance. The resultant temperature gradient in amorphous carbon or RGO drives the migration of carbon atoms and promotes the growth of CNTs without using a catalyst or external carbon source. Our findings on the growth of CNTs in confined spaces by fast high temperature Joule heating shed light on the controlled transition between different carbon allotropes, which can be extended to the growth of other high aspect ratio nanomaterials.
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http://dx.doi.org/10.1155/2018/1793784DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6750109PMC
December 2018

Clear Wood toward High-Performance Building Materials.

ACS Nano 2019 09 10;13(9):9993-10001. Epub 2019 Sep 10.

Department of Materials Science and Engineering , University of Maryland College Park , College Park , Maryland 20742 , United States.

Developing advanced building materials with both excellent thermal insulating and optical properties to replace common glass (thermal conductivity of ∼1 W m K) is highly desirable for energy-efficient applications. The recent development of transparent wood suggests a promising building material with many advantages, including high optical transmittance, tunable optical haze, and excellent thermal insulation. However, previous transparent wood materials generally have a high haze (typically greater than 40%), which is a major obstacle for their practical application in the replacement of glass. In this work, we fabricate a clear wood material with an optical transmittance as high as 90% and record-low haze of 10% using a delignification and polymer infiltration method. The significant removal of wood components results in a highly porous microstructure, much thinner wood cell walls, and large voids among the cellulose fibrils, which a polymer can easily enter, leading to the dense structure of the clear wood. The separated cellulose fibrils that result from the removal of the wood components dramatically weaken light scattering in the clear wood, which combined with the highly dense structure produces both high transmittance and extremely low haze. In addition, the clear wood exhibits an excellent thermal insulation property with a low thermal conductivity of 0.35 W m K (one-third of ordinary glass); thus, the application of clear wood can greatly improve the energy efficiency of buildings. The developed clear wood, combining excellent thermal insulating and optical properties, represents an attractive alternative to common glass toward energy-efficient buildings.
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http://dx.doi.org/10.1021/acsnano.9b00089DOI Listing
September 2019

Hydrophobic nanostructured wood membrane for thermally efficient distillation.

Sci Adv 2019 Aug 2;5(8):eaaw3203. Epub 2019 Aug 2.

Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, Boulder, CO 80303, USA.

Current membrane distillation (MD) is challenged by the inefficiency of water thermal separation from dissolved solutes, controlled by membrane porosity and thermal conductivity. Existing petroleum-derived polymeric membranes face major development barriers. Here, we demonstrate a first robust MD membrane directly fabricated from sustainable wood material. The hydrophobic nanowood membrane had high porosity (89 ± 3%) and hierarchical pore structure with a wide pore size distribution of crystalline cellulose nanofibrils and xylem vessels and lumina (channels) that facilitate water vapor transportation. The thermal conductivity was extremely low in the transverse direction, which reduces conductive heat transport. However, high thermal conductivity along the fiber enables efficient thermal dissipation along the axial direction. As a result, the membrane demonstrated excellent intrinsic vapor permeability (1.44 ± 0.09 kg m K s Pa) and thermal efficiency (~70% at 60°C). The properties of thermal efficiency, water flux, scalability, and sustainability make nanowood highly desirable for MD applications.
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http://dx.doi.org/10.1126/sciadv.aaw3203DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6677554PMC
August 2019

Simple Cholecystectomy Is Adequate for Patients With T1b Gallbladder Adenocarcinoma < 1 cm in Diameter.

Front Oncol 2019 22;9:409. Epub 2019 May 22.

Thyroid Center, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.

Consensus-based clinical guidelines recommend that simple cholecystectomy (SC) is adequate for T1a gallbladder adenocarcinoma (GBA), but extended cholecystectomy (EC), SC plus lymphatic dissection, should be considered for T1b and more advanced GBA. Whether lymphatic dissection is necessary for the treatment of T1b GBA remains controversial. This study attempts to better define the current criteria for local treatment of T1b GBA, by examining the relationship between lymph node (LN) metastasis and tumor size in such patients. Clinical data from patients with T1b GBA receiving curative surgical treatment between 2004 and 2015 were collected from the Surveillance, Epidemiology, and End Results (SEER) database. Baseline characteristics for the entire cohort were described, and overall survival (OS) and cancer-specific survival (CSS) were analyzed with the Kaplan-Meier method. In total, 277 patients were enrolled for further analysis; 127 underwent lymphadenectomy. Among them, 23 patients had tumors <1 cm in diameter, none of which had LN metastasis; 104 patients had tumors ≥1 cm, 15 of which had positive LNs. In the group with tumor size <1 cm, there was no significant survival difference between treatment with SC or EC ( = 0.694). A clinical benefit was observed in T1b GBA patients with a tumor size ≥1 cm receiving EC vs. those receiving SC ( = 0.012). SC was adequate for treatment of T1b GBA < 1 cm in diameter. This evidence may be included as part of current guidelines.
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http://dx.doi.org/10.3389/fonc.2019.00409DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6540819PMC
May 2019

A radiative cooling structural material.

Science 2019 May;364(6442):760-763

Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA.

Reducing human reliance on energy-inefficient cooling methods such as air conditioning would have a large impact on the global energy landscape. By a process of complete delignification and densification of wood, we developed a structural material with a mechanical strength of 404.3 megapascals, more than eight times that of natural wood. The cellulose nanofibers in our engineered material backscatter solar radiation and emit strongly in mid-infrared wavelengths, resulting in continuous subambient cooling during both day and night. We model the potential impact of our cooling wood and find energy savings between 20 and 60%, which is most pronounced in hot and dry climates.
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http://dx.doi.org/10.1126/science.aau9101DOI Listing
May 2019

Targeting EZH2 as a novel therapeutic strategy for sorafenib-resistant thyroid carcinoma.

J Cell Mol Med 2019 07 13;23(7):4770-4778. Epub 2019 May 13.

Thyroid Center, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai Center for Thyroid Diseases, Shanghai, China.

Thyroid carcinoma is the most common endocrine malignancy. Surgery, post-operative selective iodine-131 and thyroid hormone suppression were the most common methods for the therapy of thyroid carcinoma. Although most patients with differentiated thyroid carcinoma (DTC) showed positive response for these therapeutic methods, some patients still have to face the radioactive iodine (RAI)-refractory problems. Sorafenib is an oral multikinase inhibitor for patients with advanced RAI refractory DTC. However, the side effects and drug resistance of sorafenib suggest us to develop novel drugs and strategies for the therapy of thyroid carcinoma. In this study, we firstly found that patients with sorafenib resistance showed no significant change in rapidly accelerated fibrosarcoma and VEGFR expression levels compared with sorafenib sensitive patients. Moreover, a further miRNAs screen by qRT-PCR indicated that miR-124-3p and miR-506-3p (miR-124/506) were remarkably reduced in sorafenib insensitive patients. With a bioinformatics prediction and functional assay validation, we revealed that enhancer of zeste homolog 2 (EZH2) was the direct target for miR-124/506. Interestingly, we finally proved that the sorafenib resistant cells regained sensitivity for sorafenib by EZH2 intervention with miR-124/506 overexpression or EZH2 inhibitor treatment in vitro and in vivo, which will lead to the decreased tri-methylation at lysine 27 of histone H3 (H3K27me3) and increased acetylated lysine 27 of histone H3 (H3K27ac) levels. Therefore, we conclude that the suppression of EZH2 represents a potential target for thyroid carcinoma therapy.
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http://dx.doi.org/10.1111/jcmm.14365DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6584518PMC
July 2019

Cellulose ionic conductors with high differential thermal voltage for low-grade heat harvesting.

Nat Mater 2019 06 25;18(6):608-613. Epub 2019 Mar 25.

Department of Materials Science and Engineering, University of Maryland College Park, College Park, MD, USA.

Converting low-grade heat into useful electricity requires a technology that is efficient and cost effective. Here, we demonstrate a cellulosic membrane that relies on sub-nanoscale confinement of ions in oxidized and aligned cellulose molecular chains to enhance selective diffusion under a thermal gradient. After infiltrating electrolyte into the cellulosic membrane and applying an axial temperature gradient, the ionic conductor exhibits a thermal gradient ratio (analogous to the Seebeck coefficient in thermoelectrics) of 24 mV K-more than twice the highest value reported until now. We attribute the enhanced thermally generated voltage to effective sodium ion insertion into the charged molecular chains of the cellulosic membrane, which consists of type II cellulose, while this process does not occur in natural wood or type I cellulose. With this material, we demonstrate a flexible and biocompatible heat-to-electricity conversion device via nanoscale engineering based on sustainable materials that can enable large-scale manufacture.
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http://dx.doi.org/10.1038/s41563-019-0315-6DOI Listing
June 2019

A nanofluidic ion regulation membrane with aligned cellulose nanofibers.

Sci Adv 2019 Feb 22;5(2):eaau4238. Epub 2019 Feb 22.

Department of Materials Science and Engineering, University of Maryland College Park, College Park, MD 20742, USA.

The advancement of nanofluidic applications will require the identification of materials with high-conductivity nanoscale channels that can be readily obtained at massive scale. Inspired by the transpiration in mesostructured trees, we report a nanofluidic membrane consisting of densely packed cellulose nanofibers directly derived from wood. Numerous nanochannels are produced among an expansive array of one-dimensional cellulose nanofibers. The abundant functional groups of cellulose enable facile tuning of the surface charge density via chemical modification. The nanofiber-nanofiber spacing can also be tuned from ~2 to ~20 nm by structural engineering. The surface-charge-governed ionic transport region shows a high ionic conductivity plateau of ~2 mS cm (up to 10 mM). The nanofluidic membrane also exhibits excellent mechanical flexibility, demonstrating stable performance even when the membrane is folded 150°. Combining the inherent advantages of cellulose, this novel class of membrane offers an environmentally responsible strategy for flexible and printable nanofluidic applications.
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http://dx.doi.org/10.1126/sciadv.aau4238DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6386557PMC
February 2019

One-Step, Catalyst-Free, Scalable in Situ Synthesis of Single-Crystal Aluminum Nanowires in Confined Graphene Space.

ACS Appl Mater Interfaces 2019 Feb 29;11(6):6009-6014. Epub 2019 Jan 29.

Department of Materials Science and Engineering , North Carolina State University , Raleigh , North Carolina 27606 , United States.

Nanowires have a wide range of applications, such as transparent electrodes, Li-ion battery anodes, light-emitting diodes, solar cells, and electronic devices. Currently, aluminum (Al) nanowires can be synthesized by thermally induced substitution of germanium (Ge) nanowires, chemical vapor deposition on other metal substrates, and template-assisted growth methods. However, there are still challenges in fabricating extremely high-purity nanowires, large-scale manufacturing, and simplifying the synthesis process and conditions. Here, we report for the first time that single-crystal Al nanowires can be one-step, in situ synthesized on a reduced graphene oxide (RGO) substrate on a large scale without using any catalysts. Through a simple high temperature treatment process, commercial micro-sized Al powders in RGO film were transformed into a single-crystal Al nanowire with an average length of 1.2 μm and an average diameter of 18 nm. The possible formation mechanism of the single-crystal Al nanowires is proposed as follows: hot aluminum atoms eject from the pristine aluminum/alumina core/shell structure of Al powders when they build up enough energy from the thermal stress under high temperature and confined space conditions, which is supported by both experimental and computational results. The method introduced here can be extended to allow the synthesis of one-dimensional highly reactive materials, like alkali metal nanowires, in confined spaces.
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http://dx.doi.org/10.1021/acsami.8b18977DOI Listing
February 2019

An Electron/Ion Dual-Conductive Alloy Framework for High-Rate and High-Capacity Solid-State Lithium-Metal Batteries.

Adv Mater 2019 Jan 21;31(3):e1804815. Epub 2018 Nov 21.

Department of Materials Science and Engineering, University of Maryland at College Park, College Park, MD, 20742, USA.

The solid-state Li battery is a promising energy-storage system that is both safe and features a high energy density. A main obstacle to its application is the poor interface contact between the solid electrodes and the ceramic electrolyte. Surface treatment methods have been proposed to improve the interface of the ceramic electrolytes, but they are generally limited to low-capacity or short-term cycling. Herein, an electron/ion dual-conductive solid framework is proposed by partially dealloying the Li-Mg alloy anode on a garnet-type solid-state electrolyte. The Li-Mg alloy framework serves as a solid electron/ion dual-conductive Li host during cell cycling, in which the Li metal can cycle as a Li-rich or Li-deficient alloy anode, free from interface deterioration or volume collapse. Thus, the capacity, current density, and cycle life of the solid Li anode are improved. The cycle capability of this solid anode is demonstrated by cycling for 500 h at 1 mA cm , followed by another 500 h at 2 mA cm without short-circuiting, realizing a record high cumulative capacity of 750 mA h cm for garnet-type all-solid-state Li batteries. This alloy framework with electron/ion dual-conductive pathways creates the possibility to realize high-energy solid-state Li batteries with extended lifespans.
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http://dx.doi.org/10.1002/adma.201804815DOI Listing
January 2019

Interface Engineering for Garnet-Based Solid-State Lithium-Metal Batteries: Materials, Structures, and Characterization.

Adv Mater 2018 Nov 9;30(48):e1802068. Epub 2018 Oct 9.

Department of Materials Science and Engineering, University of Maryland, College Park, MD, 20742, USA.

Lithium-metal batteries are considered one of the most promising energy-storage systems owing to their high energy density, but their practical applications have long been hindered by significant safety concerns and poor cycle stability. Solid-state electrolytes (SSEs) are expected to improve not only the safety but also the energy density of Li-metal batteries. The key challenge for solid-state Li-metal batteries lies in the low ionic conductivity of the SSEs and moreover the interface contact between the electrode and SSE. To achieve feasible solid-state Li-metal batteries, it is imperative that the ionic conductivity is improved, especially at the electrode-SSE interface. Herein, recent advances in interface engineering for solid-state Li-metal batteries are reported, mainly focusing on garnet-type SSEs. Various materials to modify the cathode-garnet and Li-garnet interfaces by intermediate layers, alloys, and polymer electrolytes are analyzed. Structural innovations for SSEs including composite electrolytes and multilayer SSE frameworks are reviewed, along with advanced characterization approaches to probe the interfaces, which will provide further insights for garnet-based solid-state batteries. Future challenges and the great promise of garnet-based Li-metal batteries are discussed to close.
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http://dx.doi.org/10.1002/adma.201802068DOI Listing
November 2018

Isotropic Paper Directly from Anisotropic Wood: Top-Down Green Transparent Substrate Toward Biodegradable Electronics.

ACS Appl Mater Interfaces 2018 Aug 15;10(34):28566-28571. Epub 2018 Aug 15.

Department of Materials Science and Engineering , University of Maryland , College Park , Maryland 20742 , United States.

Flexible electronics have found useful applications in both the scientific and industrial communities. However, substrates traditionally used for flexible electronics, such as plastic, cause many environmental issues. Therefore, a transparent substrate made from natural materials provides a promising alternative because it can be degraded in nature. The traditional bottom-up fabrication method for transparent paper is expensive, environmentally unfriendly, and time-consuming. In this work, for the first time, we developed a top-down method to fabricate isotropic, transparent paper directly from anisotropic wood. The top-down method includes two steps: a delignification process to bleach the wood by lignin removal and a pressing process for removing light-reflecting and -scattering sources. The resulting isotropic, transparent paper has high transmittance of about 90% and high haze over 80% and is demonstrated as a nature-disposable substrate for electronic/optical devices. Adjusting the pressing ratio used changes the density of the resulting paper, which tunes the microstructure-related properties of the isotropic, transparent paper. This top-down method is simple, fast, environmentally friendly, and cost-effective, which can greatly promote the development of paper-based green optical and electronic devices.
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http://dx.doi.org/10.1021/acsami.8b08055DOI Listing
August 2018

Three-Dimensional, Solid-State Mixed Electron-Ion Conductive Framework for Lithium Metal Anode.

Nano Lett 2018 06 29;18(6):3926-3933. Epub 2018 May 29.

Maryland Energy Innovation Institute , College Park , Maryland 20742 , United States.

Solid-state electrolytes (SSEs) have been widely considered as enabling materials for the practical application of lithium metal anodes. However, many problems inhibit the widespread application of solid state batteries, including the growth of lithium dendrites, high interfacial resistance, and the inability to operate at high current density. In this study, we report a three-dimensional (3D) mixed electron/ion conducting framework (3D-MCF) based on a porous-dense-porous trilayer garnet electrolyte structure created via tape casting to facilitate the use of a 3D solid state lithium metal anode. The 3D-MCF was achieved by a conformal coating of carbon nanotubes (CNTs) on the porous garnet structure, creating a composite mixed electron/ion conductor that acts as a 3D host for the lithium metal. The lithium metal was introduced into the 3D-MCF via slow electrochemical deposition, forming a 3D lithium metal anode. The slow lithiation leads to improved contact between the lithium metal anode and garnet electrolyte, resulting in a low resistance of 25 Ω cm. Additionally, due to the continuous CNT coating and its seamless contact with the garnet we observed highly uniform lithium deposition behavior in the porous garnet structure. With the same local current density, the high surface area of the porous garnet framework leads to a higher overall areal current density for stable lithium deposition. An elevated current density of 1 mA/cm based on the geometric area of the cell was demonstrated for continuous lithium cycling in symmetric lithium cells. For battery operation of the trilayer structure, the lithium can be cycled between the 3D-MCF on one side and the cathode infused into the porous structure on the opposite side. The 3D-MCF created by the porous garnet structure and conformal CNT coating provides a promising direction toward new designs in solid-state lithium metal batteries.
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http://dx.doi.org/10.1021/acs.nanolett.8b01295DOI Listing
June 2018

Epitaxial Welding of Carbon Nanotube Networks for Aqueous Battery Current Collectors.

ACS Nano 2018 Jun 17;12(6):5266-5273. Epub 2018 May 17.

Department of Materials Science and Engineering , University of Maryland , College Park , Maryland 20742 , United States.

Carbon nanomaterials are desirable candidates for lightweight, highly conductive, and corrosion-resistant current collectors. However, a key obstacle is their weak interconnection between adjacent nanostructures, which renders orders of magnitude lower electrical conductivity and mechanical strength in the bulk assemblies. Here we report an "epitaxial welding" strategy to engineer carbon nanotubes (CNTs) into highly crystalline and interconnected structures. Solution-based polyacrylonitrile was conformally coated on CNTs as "nanoglue" to physically join CNTs into a network, followed by a rapid high-temperature annealing (>2800 K, overall ∼30 min) to graphitize the polymer coating into crystalline layers that also bridge the adjacent CNTs to form an interconnected structure. The contact-welded CNTs (W-CNTs) exhibit both a high conductivity (∼1500 S/cm) and a high tensile strength (∼120 MPa), which are 5 and 20 times higher than the unwelded CNTs, respectively. In addition, the W-CNTs display chemical and electrochemical stabilities in strong acidic/alkaline electrolytes (>6 mol/L) when potentiostatically stressing at both cathodic and anodic potentials. With these exceptional properties, the W-CNT films are optimal as high-performance current collectors and were demonstrated in the state-of-the-art aqueous battery using a "water-in-salt" electrolyte.
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http://dx.doi.org/10.1021/acsnano.7b08584DOI Listing
June 2018

Continuous plating/stripping behavior of solid-state lithium metal anode in a 3D ion-conductive framework.

Proc Natl Acad Sci U S A 2018 04 26;115(15):3770-3775. Epub 2018 Mar 26.

Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742

The increasing demands for efficient and clean energy-storage systems have spurred the development of Li metal batteries, which possess attractively high energy densities. For practical application of Li metal batteries, it is vital to resolve the intrinsic problems of Li metal anodes, i.e., the formation of Li dendrites, interfacial instability, and huge volume changes during cycling. Utilization of solid-state electrolytes for Li metal anodes is a promising approach to address those issues. In this study, we use a 3D garnet-type ion-conductive framework as a host for the Li metal anode and study the plating and stripping behaviors of the Li metal anode within the solid ion-conductive host. We show that with a solid-state ion-conductive framework and a planar current collector at the bottom, Li is plated from the bottom and rises during deposition, away from the separator layer and free from electrolyte penetration and short circuit. Owing to the solid-state deposition property, Li grows smoothly in the pores of the garnet host without forming Li dendrites. The dendrite-free deposition and continuous rise/fall of Li metal during plating/stripping in the 3D ion-conductive host promise a safe and durable Li metal anode. The solid-state Li anode shows stable cycling at 0.5 mA cm for 300 h with a small overpotential, showing a significant improvement compared with reported Li anodes with ceramic electrolytes. By fundamentally eliminating the dendrite issue, the solid Li metal anode shows a great potential to build safe and reliable Li metal batteries.
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http://dx.doi.org/10.1073/pnas.1719758115DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5899457PMC
April 2018

3D-Printing Electrolytes for Solid-State Batteries.

Adv Mater 2018 May 25;30(18):e1707132. Epub 2018 Mar 25.

Maryland Energy Innovation Institute, University of Maryland, College Park, MD, 20742, USA.

Solid-state batteries have many enticing advantages in terms of safety and stability, but the solid electrolytes upon which these batteries are based typically lead to high cell resistance. Both components of the resistance (interfacial, due to poor contact with electrolytes, and bulk, due to a thick electrolyte) are a result of the rudimentary manufacturing capabilities that exist for solid-state electrolytes. In general, solid electrolytes are studied as flat pellets with planar interfaces, which minimizes interfacial contact area. Here, multiple ink formulations are developed that enable 3D printing of unique solid electrolyte microstructures with varying properties. These inks are used to 3D-print a variety of patterns, which are then sintered to reveal thin, nonplanar, intricate architectures composed only of Li La Zr O solid electrolyte. Using these 3D-printing ink formulations to further study and optimize electrolyte structure could lead to solid-state batteries with dramatically lower full cell resistance and higher energy and power density. In addition, the reported ink compositions could be used as a model recipe for other solid electrolyte or ceramic inks, perhaps enabling 3D printing in related fields.
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http://dx.doi.org/10.1002/adma.201707132DOI Listing
May 2018