POLYMER ENGINEERING AND SCIENCE
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2021
·Vol. 61
·期 5
·1415-1426
·
IF 2.428
Fangjuan Wu,Anlin Chen,Hanlu Pan,Denghui Li,Lingjie Zhang,Hui Fang,Xiangfang Peng,Elena Bekyarova
Three-dimensional boron nitride/graphene nanoplatelets (3D-BN-GNP) scaffolds were fabricated using an ice-templating method and polyamide 6 (PA6)-based composites were prepared by vacuum impregnation of caprolactam monomers into the scaffolds, followed by polymerization. The BN sheets in the PA6/3D-BN and PA6/3D-BN-GNP composites display a predominant parallel alignment along the ice-crystal formation constructing thermally conductive paths. The addition of few GNPs assists the dispersion of BN sheets in the PA6/3D-BN-GNP composites and repair the broken thermal paths caused by local agglomeration of the BN sheets. Consequently, GNPs play a morphology-promoted synergistic role in the enhancement of the thermal conductivity of the PA6/3D-BN-GNP composites. The PA6/3D-BN-GNP composite prepared with 23.40 wt% BN sheets and 2.60 wt% GNPs exhibits the highest thermal conductivity of 2.80 W m −1 K −1 , which is 833% and 33% higher than the values recorded for the pure PA6 and the PA6/3D-BN composite at BN loading of 26.18 wt%, respectively. Infrared imaging analysis revealed that the surface of the PA6/3D-BN-GNP composite has a fast response to heating and cooling, suggesting the potential of the composites in thermal management applications.
研究领域:
材料科学
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热传导工程
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DOI
高影响因子
CARBON
·
2021
·
IF 9.594
Can Liao,Yanbei Hou,Longfei Han,Yulu Zhu,Huijuan Wang,Na Wu,Yuan Hu,Yongchun Kan,Lei Song
Eco-friendly carbon-based anodes are highly attractive for use as anode materials in lithium-ion batteries because of their accessibility, high conductivity, and satisfactory storage capacity. However, to date, the carbon anodes reported in literature exhibit low capacity, poor cycling stability, and cannot meet the current increasing demands for materials that possess high energy density . Herein, highly nitrogen-doped expandable carbon-based anodes are developed using the zeolitic imidazolate frameworks (ZIFs) ZIF-67 and ZIF-8 as self-sacrificial templates. Compared with pure carbon anodes, such as graphene oxide (GO) and carbon nanotubes (CNTs), the expandable N-doped with small size CNTs decorated GO (NC-GO) and CNTs (NC-CNTs) anodes developed in this work exhibit gradually increasing reversible specific capacities, as well as high capacities of 790 and 800 mA h g −1 , respectively, which can be sustained even after 500 cycles at 100 mA g −1 . Moreover, the anodes show ultralong cycling lives with extremely low capacity loss rates in each cycle of 0.0042% for NC-GO over 7000 cycles and 0.0035% for NC-CNTs over 10,000 cycles, which are superior to those in the current literature. This work details a new vision and direction for the development of high-capacity ultralong cycling life carbon-based anodes for use in next generation rechargeable energy storage systems .
研究领域:
材料科学
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能源存储
✓ 已验证
DOI
高影响因子
Journal of Environmental Sciences
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2020
·
IF 4.302
Yao Xiao,Honghong Lyu,Chengliang Yang,Beibei Zhao,Lan Wang,Jingchun Tang
In order to enhance the removal performance of graphitic carbon nitride (g-C 3 N 4 ) on organic pollutant , a simultaneous process of adsorption and photocatalysis was achieved via the compounding of biochar and g-C 3 N 4 . In this study, g-C 3 N 4 was obtained by a condensation reaction of melamine at 550°C. Then the g-C 3 N 4 /biochar composites were synthesized by ball milling biochar and g-C 3 N 4 together, which was considered as a simple, economical, and green strategy. The characterization of resulting g-C 3 N 4 /biochar suggested that biochar and g-C 3 N 4 achieved effective linkage. The adsorption and photocatalytic performance of the composites were evaluated with enrofloxacin (EFA) as a model pollutant. The result showed that all the g-C 3 N 4 /biochar composites displayed higher adsorption and photocatalytic performance to EFA than that of pure g-C 3 N 4 . The 50% g-C 3 N 4 /biochar performed best and removed 45.2% and 81.1% of EFA (10 mg/L) under darkness and light with a dosage of 1 mg/mL, while g-C 3 N 4 were 19.0% and 27.3%, respectively. Besides, 50% g-C 3 N 4 /biochar showed the highest total organic carbon (TOC) removal efficiency (65.9%). Radical trapping experiments suggested that superoxide radical (•O 2 − ) and hole (h + ) were the main active species in the photocatalytic process. After 4 cycles, the composite still exhibited activity for catalytic removal of EFA.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
POLYMER ENGINEERING AND SCIENCE
·
2022
·Vol. 62
·期 5
·1641-1649
·
IF 2.573
Hui Fang,Anlin Chen,Lingjie Zhang,Sheng Chen,Fangjuan Wu,Hui Chen
Three-dimensional boron nitride/zinc oxide (3D-BN-ZnO) scaffolds were prepared by the ice-templating method, in which ZnO particles were in situ formed by sintering. Then, polydimethylsiloxane (PDMS)/3D-BN-ZnO composites were fabricated via vacuum infiltration of PDMS prepolymer into the scaffolds and curing. Compared with the composite prepared by simple blending, the thermal conductivity of the composite prepared based on the ice-templating method is much higher due to the excellent orientation of hexagonal boron nitride (hBN) sheets. Based on the same content of hBN sheets, the further introduction of 2.7 wt% ZnO particles formed in situ by sintering could promote the thermal conductivity of the composite to the value of 1.45 W m −1 K −1 , which is 70.6% higher than that of the PDMS/3D-BN composite. In addition, compared with the PDMS/3D-BN composite containing more hBN sheets, the PDMS/3D-BN-ZnO composite with 2.7 wt% ZnO particles possesses fewer fillers but higher thermal conductivity. It suggests that ZnO particles could synergistically improve the thermal conductivity. As revealed from the morphology of the composites, many ZnO particles are located between hBN sheets and thus construct thermally conductive paths. This study provides a new strategy for the design of thermal interface materials with high thermal conductivity.
研究领域:
材料科学
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热管理技术
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DOI
高影响因子
ACS Nano
·
2021
·
IF 15.881
Peilong Lu,Xin Tan,Haitao Zhao,Qian Xiang,Kaili Liu,Xiaoxu Zhao,Xinmao Yin,Xinzhe Li,Xiao Hai,Shibo Xi,Andrew T S Wee,Stephen J. Pennycook,Xuefeng Yu,Menglei Yuan,Jianbo Wu,Guangjin Zhang,Sean C. Smith,Zongyou Yin
An atomically dispersed structure is attractive for electrochemically converting carbon dioxide (CO2) to fuels and feedstock due to its unique properties and activity. Most single-atom electrocatalysts are reported to reduce CO2 to carbon monoxide (CO). Herein, we develop atomically dispersed indium (In) on a nitrogen-doped carbon skeleton (In–N–C) as an efficient catalyst to produce formic acid/formate in aqueous media, reaching a turnover frequency as high as 26771 h–1 at −0.99 V relative to a reversible hydrogen electrode (RHE). Electrochemical measurements show that trace amounts of In loaded on the carbon matrix significantly improve the electrocatalytic behavior for the CO2 reduction reaction, outperforming conventional metallic In catalysts. Further experiments and density functional theory (DFT) calculations reveal that the formation of intermediate *OCHO on isolated In sites plays a pivotal role in the efficiency of the CO2-to-formate process, which has a lower energy barrier than that on metallic In.
研究领域:
化学
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材料科学
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催化反应
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2020
·
IF 3.807
Xiuxian He,Zheng Tang,LianLian Gao,Fangyuan Wang,Jinping Zhao,Zhichao Miao,Xiaozhong Wu,Jin Zhou,Yang Su,Shuping Zhuo
Engineering graphene with efficient ion and electron transport properties is vital for development of high performance, next generation energy storage devices. The protocols generally involve pore generation and doping of graphene with the heteroatoms. Herein we report the realization of pore generation, control, and N-doping of graphene in one single process using reduced metal salt as etching agent and environment friendly N 2 gas as doping agent. Furthermore, we found the porous structure (pore size and density), the dopant bonding configuration and doping amount can be controlled by change the metal salt and nitrogen source, which allows us to investigate the influence of pore and N-doping structure of porous graphene (PG) in their supercapacitor performance . Specifically, the N-doping, PG prepared by Ni salt (PG-Ni) shows the smaller pore size (average pore size of ~20–30 nm) and larger pore density. PG-Ni exhibits high specific capacitance of 575 F/g along with the energy density of 51.2 Wh/kg at 0.5 A/g current density and also shows good rate, cycling performances. Considering the excellent performance, ease of the process, and pore structure controllability, we believe the method provides a new route for developing graphene based high performance supercapacitors.
研究领域:
材料科学
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能源工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
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2022
·
IF 5.532
Luyan Yao,Changming Ke,Jinhua Zhang,Yuanbing Li,Bingqiang Han,Jingran Wang
Ti–Si–Fe alloys extracted from high-titanium blast furnace slag were utilized to replace part of the silicon powders, and then nitride/oxynitride bonded SiC ceramics were prepared by reactive sintering in graphite bed. Ti–Si–Fe alloys could react with CO/N 2 at a low temperature (1200 °C), and the addition of Ti–Si–Fe alloys could reduce the nitriding temperature of Si. Density functional theory calculations suggested that Ti–Si–Fe alloys enhanced reaction activity via weakening the strength of C O and N N bonds. The regional equilibrium phase diagrams of Si–C–N–O and Ti–Si–C–N–O under CO/N 2 atmosphere were calculated by thermodynamics. The change of whiskers morphology was observed by scanning electron microscope. Furthermore, the bulk density, the cold modulus of rupture, and the cold compressive strength improved with Ti–Si–Fe alloys content. The results showed that the addition of Ti–Si–Fe alloys not only significantly promoted nitriding of Si and formation of Si 3 N 4 whiskers, but also improved the mechanical properties of the samples.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2020
·
IF 16.683
Hao Huang,Xu-Sheng Wang,Davin Philo,Fumihiko Ichihara,Hui Song,Yunxiang Li,Dan Li,Teng Qiu,Shengyao Wang,Jinhua Ye
The fixation of atmospheric dinitrogen to ammonia is one of the most essential processes for sustaining life. Since the N N bond in dinitrogen is one of the strongest bonds in chemistry, it remains a grand challenge to develop efficient catalysts for fixation of N 2 under ambient conditions. Herein we report for the first time on visible-light-assisted photocatalytic nitrogen fixation by metal organic framework material at room temperature and pressure. The Ti 3+ species induced by electron transfer from ligand-to-metal charge transfer process provide active sites for N 2 reduction. Furthermore, visible-light-assisted photocatalytic N 2 fixation is achieved by ligands functionalization which extend the light harvesting of the MOF to visible region. The integration of Ti sites and amine-functionalized linkers in NH 2 -MIL-125 (Ti) shows the highest visible light photocatalysis efficiency at a rate of 12.3 μmol g −1 h −1 . This Ti MOF system therefore shows a potential as a new design of combining light-harvesting and catalytic components in a single solid platform for green NH 3 production.
研究领域:
化学
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材料科学
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环境科学
✓ 已验证
DOI
高影响因子
RENEWABLE ENERGY
·
2022
·
IF 8.634
Ruijie Chen,Zhiqiang Zhang,Jun Wu,Xueru Chen,Lei Wang,Haotian Yin,Hongping Li,Jing Ding,Hui Wan,Guofeng Guan
The fabrication of graphitic carbon nitride (g-C 3 N 4 ) has received much attention for its superior photoelectronic properties, it remains a remarkable challenge with a feasible methodology. Herein, inspired by carburization , a novel method with carbon diffusion was proposed to prepare g-C 3 N 4 nanosheets (CNNS). The carbon diffusion was caused by the gradient difference in carbon concentration between the gaseous environment and the C15 (mild steel with low carbon content) during thermal polymerization . Eventually, the CNNS with approximately 1.5 nm thickness was successfully fabricated and exhibited larger surface area (98.08 m 2 g −1 ), which was 15.42 times higher than that of bulk g-C 3 N 4 (BCN). In the evaluation of photocatalytic CO 2 reduction activity, the CH 3 OH formation rate over CNNS (2.10 μmol g −1 h −1 ) was 3.28 times greater than BCN. Meanwhile, the designed CNNS exhibited dramatic improvement on H 2 evolved rate (HER) of 2507.02 μmol g −1 h −1 , which was 6.99 times higher than BCN. More importantly, the C15 possessed the advantage of 10 times recycled to use for the fabrication of CNNS accompanied by a moderate decrease of HER. Moreover, the density functional theory (DFT) calculations were carried out based on the results. This work highlights an ingenious tactic with carbon diffusion for preparing CNNS towards renewable solar energy conversion .
研究领域:
材料科学
·
能源科学
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DOI
高影响因子
Nano Energy
·
2020
·
IF 16.602
Zhenqing Zhao,Changhyeok Choi,Song Hong,Huidong Shen,Chao Yan,Justus Masa,Yousung Jung,Jieshan Qiu,Zhenyu Sun
Solar N 2 fixation under visible light offers a promising method toward sustainable NH 3 production at benign conditions. However, it still remains a formidable challenge to activate and cleave N N bonds and promote the separation and transport of electrons and holes during photocatalysis . To address these issues, the discovery and design of high-performance and robust photocatalysts is imperative. Here, we report the defect engineering of two-dimensional oxidized Sb nanosheets to activate intrinsically inactive Sb for efficient visible light-driven N 2 reduction to NH 3 . Impressively, the Sb nanosheets rich in Sb and oxygen vacancies afford a remarkable NH 3 formation rate of up to 388.5 μg NH3 h −1 g cat. −1 without cocatalyst in visible light, 8 times higher than that for bulk Sb and also significantly outperforming many previously reported photocatalysts. The defective Sb nanosheets exhibit excellent stability after five successive reaction cycles. Further density functional theory calculations reveal a considerably strong interaction between N 2 and defects on the surface and edge of Sb nanosheets , which facilitates the formation of *NNH (N 2 + (H + + e - ) → *NNH, where * denotes an adsorption site), thus promoting photocatalytic N 2 reduction. This finding opens a novel avenue to enhancing N 2 photofixation over inherently inactive surfaces by synergistically engineering defect sites.
研究领域:
材料科学
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催化化学
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2021
·
IF 5.097
Xue-Chun Yang,Yun-Ling Yang,Meng-Meng Xu,Shan-Shan Liang,Xiao-Long Pu,Jian-Feng Hu,Qian-Li Li,Jing-Tai Zhao,Zhi-Jun Zhang
Nitrogen-doped carbon dots (NCDs) synthesized by the low-temperature sintering method show electronegativity rich in −COO–, −CO–NH–, −NH–, and −OH. The structure, morphology, and fluorescence performance of NCDs were successively characterized by Fourier-transform, infrared, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, photoluminescence, ultraviolet (UV), and X-ray fluorescence analyses. On the one hand, NCDs can sensitively detect Pb2+ in water with a detection limit of 3 ppb through the dual response of fluorescence emission spectra and UV absorbance spectra. On the other hand, the negatively charged NCDs combine with various positively charged heavy metal ions (Pb2+, Cu2+, Ni2+, Co2+, and Cd2+) through charge attraction and coordination to form a hydrogel, thereby removing heavy metal ions from the water. Among them, the removal rate of Pb2+ by NCDs is as high as 94.8%. It is the first time that pure NCDs have been used to remove heavy metal ions quickly and easily in the form of a reversible hydrogel. A simple way is to achieve ultrasensitive detection and high-efficiency removal of heavy metal ions in water with unitary NCDs.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF FOOD PROCESSING AND PRESERVATION
·
2020
·Vol. 45
·期 2
·e15139
·
IF 1.405
Yue-ming Hu,Nan-hai Zhang,Hui Wang,Yi-fan Yang,Zong-cai Tu
Pengze crucian carp was pre-frozen by liquid nitrogen and freezer, and then stored at −20/−40°C and −20°C, respectively, for 15–60 days. Effects of pre-freezing methods and storage temperatures on the qualities of fish were investigated. The pH showed a “V” trend. The soluble myofibrillar protein content, hardness, springiness, cohesiveness, gumminess, chewiness, and resilience decreased. Thiobarbituric acid value, total volatile basic-nitrogen value, thawing and cooking loss rates increased with the extending of storage period. LF-NMR analysis indicated that the water-protein connection became less tight. Moreover the qualities decline degrees were higher for freezer pre-frozen than liquid nitrogen pre-frozen, and higher for −20°C storage than −40°C storage. Accordingly, compared with conventional freezer pre-freezing and storage, liquid nitrogen pre-freezing and low temperature storage could inhibit the oxidation and degradation, and keep better water holding and textural properties of muscle. The present study showed a great potential application in aquatic products processing industry. Practical applications In aquatic product enterprise, liquid nitrogen can be used to pre-freeze fishes in seconds. And combined with low temperature storage, the oxidation and degradation of fish can be significantly inhibited. In addition, water holding capacity and textural properties of fish muscle can be better kept, and the shelf-life of fish can be extended by several weekends in comparison with those of fishes pre-frozen and stored in freezer.
研究领域:
食品科学
·
水产加工
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）