Journal of Materials Chemistry A
·
2020
·Vol. 9
·期 7
·3985-3994
·
IF 11.301
Ruidi Wang,Bei-Bei Xu,Jiachen Wang,Xue Lu Wang,Ye-Feng Yao
The relationship between the structural characteristics and photocatalytic reaction mechanisms of graphitic carbon nitride (g-C3N4) still remains unclarified at the molecular level, which severely hinders the further development of this field. The present study addresses this issue by employing an innovative strategy to investigate the relationship between the H-containing structures of g-C3N4 and its water splitting properties. The exchangeable and unexchangeable protons of the H-containing groups of g-C3N4 were differentiated by selective deuteration, providing a way to distinguish the hydrophilic and relatively non-hydrophilic H-containing groups of g-C3N4. A combination of advanced solid-state NMR approaches reveals that amino group defects (CN2(NHx)) on the C–N skeleton of the photocatalyst likely serve as hydrophilic active sites for facilitating the photocatalytic hydrogen evolution reaction. Accordingly, the newly synthesized g-C3N4 sample having a high concentration of CN2(NHx) by design demonstrates an enhanced H2 yield by a factor of 17 compared to that of pure g-C3N4.
研究领域:
材料化学
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光催化
·
固体核磁共振
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表面科学
·
能源材料
✓ 已验证
DOI
高影响因子
MATERIALS & DESIGN
·
2016
·
IF 3.997
XinRong Liu,Ming Zhang,TingTing Yang,LiNa Wang,Han Zhu,ShunLi Wang,MingLiang Du
Carbon nanofibers served as nanoreactors for the design and construction of PtCo alloy carbon core-shell nanostructures with nitrogen doping (PtCo/NCNF) through a combination of electrospinning and nitrogen doping treatments. The PtCo/NCNF hybrid consists of PtCo alloy nanoparticles surrounded by a few of N-doped carbon layers , demonstrating a typical core-shell structures. The PtCo/NCNF hybrid can both served as electrode materials for electrocatalytic water splitting including hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). For the HER performance, the PtCo/NCNF exhibits very small onset potential of 20 mV, an overpotential of 50 mV at a j (vs RHE) = 10 mA cm − 2 and Tafel slope of 30 mV dec − 1 . The PtCo/NCNF hybrid also exhibits high OER activity with an onset potential of 310 mV, an overpotential of 400 mV at a j of 10 mA cm − 2 and a small Tafel slope of 76 mV dec − 1 . The high catalytic activities of PtCo alloy for HER and OER originate from the 3D hierarchical structures, well-dispersed PtCo alloy, high conductivity of NCNF, protection from the carbon-encapsulated structure, and the introduction of nitrogen.
研究领域:
材料科学
·
纳米技术
·
电化学
·
能源化学
·
催化化学
·
功能材料
✓ 已验证
DOI
高影响因子
MATERIALS & DESIGN
·
2017
·
IF 4.364
Puhong Wen,Lili Ai,Fenyan Wei,Dengwei Hu,Jingjing Guo,Fangyi Yao,Taotao Liu
The crystalline hexagonal Nb 2 O 5 (H-Nb 2 O 5 ) nanobelt clusters dominantly exposed (− 110) facet are firstly synthesized by a hydrothermal topological reaction with a precursor of fiber-like K 2 Nb 2 O 6 ·H 2 O. The structure and morphology of samples obtained at different temperatures and times are investigated. There are two steps in the synthesis process. One is the acid-exchanging reaction transforming into amorphous phase protonated niobate (HNO), and the other is dehydration reaction transforming into H-Nb 2 O 5 , and simultaneous dissolution reaction which forms nanobelt cluster morphology from the fiber-like particle. The formation mechanism of H-Nb 2 O 5 nanobelt clusters has been proposed in detail. After photo-reduced reaction between the H-Nb 2 O 5 nanobelt clusters and AgNO 3 solution, the dominantly exposed (− 110) facet of H-Nb 2 O 5 nanobelt is homogeneously covered by Ag nanoparticles . The photo-electrochemical performance of the obtained H-Nb 2 O 5 nanobelt clusters and Ag deposited H-Nb 2 O 5 (Ag-Nb 2 O 5 ) nanobelt clusters as photocatalysts are evaluated by splitting water under simulated sunlight illumination, and the generated photocurrent of Ag-Nb 2 O 5 sample is 10.73 μA, which is 535 times that of the H-Nb 2 O 5 sample. The results demonstrate that the Ag-Nb 2 O 5 nanobelt clusters have a high photo-electrochemical performance as well as good sunlight photoelectric conversion efficiency.
研究领域:
材料科学
·
纳米科技
·
光催化
·
能源化学
·
半导体材料
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电化学
·
太阳能转换
✓ 已验证
DOI
高影响因子
FUEL
·
2021
·
IF 6.609
Hongsheng Yu,Suhang Chen,Xiaodong Yu,Wei Zhang,Christian Paravan,Luigi T. DeLuca,Ruiqi Shen
The slow regression rate induced by the difficulty of pyrolysis has limited the practical application of hydroxyl-terminated polybutadiene (HTPB)-based fuels for hybrid rocket propulsion. A possible strategy is the use of suitable transition metal elements promoting polymer matrix thermal decomposition of fuels. This paper investigates the effects of nickel acetylacetonate, Ni(acac) 2 , on the thermal stability and combustion of HTPB-based fuel formulations. The presented experimental results show that the addition of Ni(acac) 2 can intensely decrease the thermal stability of HTPB thus enhancing the solid fuel regression rate even at a small additive mass fraction: under an oxygen mass flux of 50 kg/m 2 s, HTPB + 5 wt% Ni(acac) 2 shows a 25.5% increase over the non-loaded baseline. Kinetics analyses reveal that the catalytic effect is mainly induced by the Ni 2+ in Ni(acac) 2 at the early stage of decomposition, and by the NiO produced from the oxidative decomposition of Ni(acac) 2 in the fuel final degradation stage. On the other hand, the addition of Ni(acac) 2 decreases the combustion heat of HTPB-based fuels significantly and implies the accumulation of its decomposition products (much metal Ni, moderate elemental C, and a little NiO.) at the fuel regressing surface. Eventually, when the content of Ni(acac) 2 exceeds 5 wt%, the growth of regression rate slows down rapidly, and a performance detriment occurs at 40 wt%. This study verifies the catalytic effect of Ni(acac) 2 on polymer matrix for HTPB based fuels showing the attractive regression rate performance of this additive.
研究领域:
推进剂化学
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燃烧学
·
高分子材料科学
·
航天动力工程
·
催化化学
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2022
·
IF 13.599
Xin Wu,Xingyu Xiong,Bin Yuan,Jun Liu,Renzong Hu
A good cycling stability is a prerequisite for the application of metal-based materials in lithium-ion batteries (LIBs). However, an abnormal increase in capacity is often observed, which has rarely been focused on in many studies. In our SnSe-Mo-C composite anode, a high reversible capacity of 737.4 mAh g −1 remained after 5000 cycles at 5 A g −1 between 0.01 and 3.0 V versus Li/Li + . However, a continuous capacity increase occurred in the initial cycles, with 1086.9 mAh g −1 after 1000 cycles and 1216.9 mAh g −1 after 1500 cycles, respectively. Further studies revealed that the electrolyte decomposed at high potentials (2.5–3.0 V) and provided additional capacities. The cut-off voltage and electrolyte filling were controlled, which eliminated the impact of electrolyte decomposition, prevented rapid capacity decay, and provided a stable cycling performance for SnSe-Mo-C anodes in LIBs. This work shows that the composite anode is promising for lithium storage and the findings provide new insights into understanding and controlling the phenomenon of capacity increase with cycling in metal-based anode materials.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米材料
·
电池技术
✓ 已验证
DOI
高影响因子
Solar RRL
·
2021
·Vol. 6
·期 4
·2100798
·
IF 8.582
Manjing Wang,Sanlong Wang,Qixing Zhang,Sanjiang Pan,Ying Zhao,Xiaodan Zhang
Finding a cost-effective semiconductor with commercial performance for photoelectrochemical (PEC) water splitting remains challenging. Sb 2 Se 3 , as a low-cost semiconductor, has excellent photo/electric properties for PEC water splitting. Via adjusting the Sb/Se ratio in the precursor ink, the Sb 2 Se 3 with favorable crystallographic orientation can be effectively controlled. The ink with an atomic ratio of Sb/Se = 1:3 induces the growth of a compact Sb 2 Se 3 film with a preferred orientation, resulting in rapid charge transport and high photocurrent. After depositing TiO 2 and Pt in turn, the photocathode with a structure of FTO/Au/Sb 2 Se 3 /TiO 2 /Pt exhibits a photocurrent density of 11.3 mA cm −2 at 0 V RHE . An unassisted solar water splitting device integrating the Sb 2 Se 3 -based photocathode with an inorganic perovskite photovoltaic cell achieves a solar-to-hydrogen efficiency of 2.45%. The efficient Sb 2 Se 3 -based photocathode shows promising potential for solar fuel production.
研究领域:
材料科学
·
物理化学
·
能源化学
·
半导体光电化学
·
可再生能源
✓ 已验证
DOI
高影响因子
Advanced Materials Interfaces
·
2018
·Vol. 6
·期 3
·1801663
·
IF 4.834
Wentian Huang,Qingwei Zhou,Shaoqiang Su,Jing Li,Xubin Lu,Xingsen Gao,Xin Wang,Mingliang Jin,Guofu Zhou,Zhang Zhang,Junming Liu
Loading 2D layered transition metal dichalcogenides (TMDs) on p-type silicon photocathode is suitable for hydrogen production in solar-driven photoelectrochemical (PEC) water splitting. Similarly, various nanostructured TMDs exposing more active sites are widely explored for improving the PEC performances of composite photoelectrodes. Here, defect engineering using a controllable argon ion beam bombardment is presented on ReS 2 /Si photocathode. The atomic vacancy defects are introduced on the 2D ReS 2 to realize high-density active sites, which significantly enhance the solar-driven hydrogen evolution reaction performance of ReS 2 /Si photocathode. The highest photocurrent density of 18.5 mA cm −2 (at 0 V vs reversible hydrogen electrode) is achieved, under a simulated sun irradiation.
研究领域:
材料科学
·
光催化
·
能源化学
·
半导体器件
·
纳米科技
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2023
·Vol. 30
·期 46
·102880-102893
·
IF 5.8
Li Yunhe,Li Hao,Zhao Baogang,Ma Yanming,Liang Peiyuan,Sun Tianjun
The escalating levels of surface ozone concentration pose detrimental effects on public health and the environment. Catalytic decomposition presents an optimal solution for surface ozone removal. Nevertheless, catalyst still encounters challenges such as poisoning and deactivation in the high humidity environment. The influence of support on catalytic ozone decomposition was examined at a gas hourly space velocity of 300 L·g −1 ·h −1 and 85% relative humidity under ambient temperature using Cu-Mn–doped oxide catalysts synthesized via a straightforward coprecipitation method. Notably, the Cu-Mn/SiO 2 catalyst exhibited remarkable performance on ozone decomposition, achieving 98% ozone conversion and stability for 10 h. Further characterization analysis indicated that the catalyst’s enhanced water resistance and activity could be attributed to factors such as an increased number of active sites, a large surface area, abundant active oxygen species, and a lower Mn oxidation state. The catalytic environment created by mixed oxides can offer a clearer understanding of their synergistic effects on catalytic ozone decomposition, providing significant insights into the development of water-resistant catalysts with superior performance. Graphical
研究领域:
环境催化
·
大气污染控制
·
材料化学
·
表面科学
·
催化化学
·
环境工程
·
功能材料
✓ 已验证
DOI
高影响因子
PROPELLANTS EXPLOSIVES PYROTECHNICS
·
2024
·Vol. 50
·期 3
·e202400232
·
IF 1.7
Bo Hao,Caixian Xu,Geng Chen,Yuangen Lu,Li Zhang
In response to issues such as poor accuracy and unstable delay times encountered in the practical use of tungsten-based delay compositions, an analysis of the combustion performance of tungsten-based delay compositions with the addition of copper oxide was conducted. This study selected five tungsten-based composite delay compositions prepared by blending tungsten-based delay compositions with copper oxide at different content, aiming to investigate the influence of varying copper oxide proportions on the combustion characteristics of tungsten-based delay compositions. Microscopic morphologies and thermal decomposition behaviors of the tungsten/copper oxide delay compositions were analyzed using scanning electron microscopy (SEM) and differential scanning calorimetry (DSC), while combustion products were examined by X-ray diffraction (XRD). The results indicate that copper oxide exerts a strong catalytic decomposition effect on tungsten-based delay compositions. Specifically, a low concentration of copper oxide enhances the combustion rate of tungsten-based delay compositions, while an increase in copper oxide content subsequently slows down the combustion rate. Notably, tungsten-based delay compositions with 9% copper oxide content demonstrate high precision, good stability, and a relatively slow combustion rate, offering a wider range of adjustability for controlling the combustion speed of delay compositions and providing a feasible method for managing the delay time range in practical applications.
研究领域:
材料科学
·
火工品技术
·
燃烧学
·
无机化学
·
功能材料
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2016
·Vol. 4
·期 25
·9816-9821
·
IF 8.262
Li Cheng,Qing Chang,Yu Chang,Nannan Zhang,Changyuan Tao,Zhaona Wang,Xing Fan
Hierarchical forest-like photoelectrodes were prepared by assembling nano-ZnO on an array of micro-metal dendrites, aiming to demonstrate the idea of highly efficient photon-harvesting inside a biomimetic dendrite structure. Via a facile aqueous electrochemical deposition process, the metal dendrites were deposited on both flat and wire substrates with different alignments, showing wide adaptability. A strong, broadband anti-reflection effect was observed, owing to the diffuse reflection inside the microdendrites. By increasing the dendrite height, the overall reflectivity of the metal electrode can be reduced from 75% to 45%, which could be further reduced to 12% after combining with acicular-leaf-like ZnO nanoarrays. Its applications in light-driven water splitting were successfully demonstrated. Taking advantage of the forest-like photoelectrode, we have artificially constructed an efficient photo-electrochemical system similar to plants in a forest, with photons harvested by the crown-like photoanodes in the sunshine, and synthetic reactions driven by the root-like electrode in the shadow.
研究领域:
材料科学
·
纳米科技
·
光电化学
·
可再生能源
·
仿生学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Dan Baohui,Mahmood ul Haq,Salah Ud Din,Shabab Hussain,Shao Wenyi,Wu Jingmin,Chi Hanwen,Zhizhen Ye,Liping Zhu
The SF 6 gas in gas-insulated switchgear (GIS) systems decomposes into SO 2 F 2 , SOF 2 , SO 2 , and H 2 S under abnormal conditions such as partial discharge. The detection of these decomposition gases with high sensitivity is essential for the safe operation of GIS devices. Herein, we report the synthesis of cerium oxide and multiwalled carbon nanotube composite (CeO 2 @MWCNTs). The CeO 2 @MWCNTs composite was characterized by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy , X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller analysis. The CeO 2 @MWCNTs composite sensor provided a response value of 7.7 at 100 ppm of SO 2 F 2 at a low operating temperature (50 °C), and the response and recovery features of the CeO 2 @MWCNTs composite sensor were recorded at 43 and 28 s, respectively. Moreover, the composite sensor exhibited excellent stability after two months. The developed CeO 2 @MWCNTs composite sensor can offer an exceptional platform for gas sensing applications in diverse fields.
研究领域:
材料科学
·
气体传感技术
·
电力设备监测
·
纳米复合材料
·
环境监测
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2021
·
IF 9.676
Yu Kang,Yujia Han,Cong Wei,Kuo Liu,Ming Tian,Chuande Huang,Chaojie Wang,Jian Lin,Baolin Hou,Xiaoli Pan,Yang Su,Lin Li,Riguang Zhang,Yong Hao,Xiaodong Wang
Thermochemical two-step CO 2 splitting is a potential approach that fixes the sustainable resource into transportable liquid fuels. However, the harsh CO 2 splitting conditions, the limited oxygen release kinetics and capacity of metal oxides block further promoted the CO yield and solar-to-fuel energy efficiency. Here, we propose a different carbon cycle assisted by Ni/La 2 O 3 via coupling methane decomposition with thermochemical CO 2 splitting, replacing conventional metal oxides cycle. Superior performance was demonstrated with methane conversion reached around 94% with almost pure H 2 generation. Encouragingly, CO 2 conversion of 98% and CO yield of 6.9 mmol g −1 derived from CO 2 were achieved, with peak CO evolution rate (402 mL min −1 g −1 ) of orders of magnitude higher than that in metal oxide process and outstanding thermodynamic solar-to-fuel energy efficiency (55.5% vs. 18.5%). This was relevant to the synergistic activation of La 2 O 3 and Ni for CO 2 in carbon cycle, thus improving CO 2 splitting reaction with carbon species.
研究领域:
能源化学
·
催化化学
·
可持续能源
·
热化学转化
·
二氧化碳利用
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）