JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2022
·
IF 9.965
Haodong Li,Haoyu Li,Zhiwei Yang,Yizhu Lai,Qing Yang,Pengxin Duan,Zhuo Zheng,Yang Liu,Yan Sun,Benhe Zhong,Zhenguo Wu,Xiaodong Guo
The application value of silicon-based anodes has not been fully realized due to the ∼ 300% volume expansion and poor electronic conductivity. In present study, mesoporous Si/C (MP-Si/C) composite with nanosized primary particles of 30–50 nm and pore diameter of 20–40 nm was proposed, which displays superior Li storage properties. Firstly, Polyacrylic acid (PAA) was applied to fulfill in-situ carbon coating and inhibit the particle growth of SiO 2 generated from tetraethyl orthosilicate (TEOS) in stöber reaction. Secondly, Mg gas was introduced to create nano-sized Si with meso -pores and three-dimensional carbon network via the gas-cutting effect. The cycling stability and rate capability were both significantly enhanced with capacity of 671 mAh/g after 400 cycles and 593 mAh/g after 500 cycles at 2 A/g and 4 A/g, respectively, which was highly relevant to the selection of carbon source PAA and its corresponding carbon coating and Mg reduction effect. Moreover, this method bypasses the use of costly nano-silicon, which provides inspiration for the commercialization of silicon-based anodes.
研究领域:
材料科学
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电化学
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2023
·
IF 4.2
Weiting Yu,Dezheng Yang,Rendan Zhu,Luzhen Liu,Yan Yu,Juntao Tang,Zhiqiao He,Jiexu Ye,Shuang Song
The photoassisted electrochemical CO2 reduction reaction (CO2RR) toward CO is considered one of the most promising routes of CO2 utilization. In this work, 2,6-diaminopyridine (2,6-DAP) with both the pyridine ring and the –NH2 functional group is utilized for the first time to functionalize the surface of the electrode. The p-Si/Ag/2,6-DAP electrode has been identified as a good catalyst with relatively high activity and CO selectivity at a low overpotential as well as good stability. The Faradaic efficiency of CO is 84.56% at an optimized potential of −0.9 V vs reversible hydrogen electrode (RHE). A synergistic mechanism has been proposed for the enhanced catalytic performance of p-Si/Ag/2,6-DAP in the CO2RR. Ag facilitates the reduction of CO2 to produce CO. 2,6-DAP helps CO2 adsorption and inhibits the competitive hydrogen evolution reaction accompanying the CO2RR under low potentials.
研究领域:
材料科学
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环境科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS & DESIGN
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2018
·
IF 4.525
Haibo Ouyang,Guibiao Li,Cuiyan Li,Jianfeng Huang,Jie Fei,Jing Lu
C/C-Zr-Si-O composites were prepared by carbothermal reduction of hydrothermal co-deposited ZrO 2 , SiO 2 , and C. The bulk density of composites reached 1.71 g/cm 3 with 8 cycles of co-deposition. The matrix of the composites includes ZrC, SiC, ZrO 2 , and SiO 2 with fine grain size (300–500 nm) and homogeneous distribution. The mass and linear ablation rate of C/C-Zr-Si-O composites were 0.112 mg/cm 2 ·s and 0.46 μm/s, respectively, under a plasma flame for 120 s. The attractive ablation resistance of the composites resulted from its unique structure, which tends to form a continuous ZrO 2 -SiO 2 glass layer in the ablation center, a layer of SiO 2 -ZrO 2 bubbles in the transition region, and fluffy SiO 2 nanowires layer in the heat-affected region. These ablation layers were barriers to restrain the diffusion of oxidative gas and heat. The C/C-Zr-Si-O composites provide an alternative ceramics system with attractive ablation resistance, while carbothermal reduction of hydrothermal co-deposited oxides is a feasible method for the structural design of carbon fiber reinforced ultra-high temperature ceramic.
研究领域:
材料科学
·
航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2021
·
IF 9.297
Fengjiao Lai,Feng Yan,Pengju Wang,Fan Qu,Xuehua Shen,Zuotai Zhang
Efficient conversion of biomass-derived carbohydrates to alkyl levulinates is an important goal of biorefinery process, but is still challenging on applicable catalyst. Ce–Si pillared montmorillonite (CeSiM) clay heterostructures , incorporated with Wells-Dawson tungstophosphoric acid (H 6 P 2 W 18 O 64 , DPW), were prepared for the first time and used as the multifunctional catalyst for direct production of ethyl levulinate (EL) from various biomass-derived sugars. The DPW introduced by sol-gel method (DPW-CeSiM) has been effectively incorporated into the framework of porous CeSiM, while part of DPW was just absorbed on the surface of CeSiM by impregnation method (DPW-CeSiM-I). The DPW-CeSiM catalyst has large specific surface area owing to the insertion of Ce–Si pillars, and possesses strong Brønsted acidity and moderate Lewis acidity originated from the incorporated DPW and the Ce-doping, respectively. Due to the well synergistic effect of porous structure and dual acid, the DPW-CeSiM catalyst efficiently catalyzed the conversion of glucose into EL with 56.2% yield and nearly 100% conversion at 170 °C for 4 h. The recyclability studies certified that DPW-CeSiM catalyst showed higher stability than DPW-CeSiM-I over cycles and could be easily recovered from consecutive alcoholysis of biomass-derived sugars. The DPW-CeSiM catalyst also displayed high activity toward the conversion of other biomass-derived carbohydrates (fructose, sucrose, cellobiose and cellulose) into EL. Therefore, this work provides an instructive strategy for the design of efficient and stable DPW-based catalysts with dual acid sites uniformly distributed over the porous structure, which is obviously potential for industrial production of alkyl levulinates from carbohydrates and biomass.
研究领域:
化学工程
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生物质能
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
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IF 8.1
Chenglong Ding,Yao Li,Wenfei Xiao,Qi Chen,Yanming Li,Jingfu He,Changli Li
Constructing p-Si based heterojunction photocathode is a promising means to convert solar energy into storable hydrogen fuel . The favorable energy band alignment between p-Si absorber and electron transport layer (ETL) is crucial to realize efficient photogenerated carrier separation and transport during photoelectrochemical water splitting . The trade-off between large Fermi level difference and optimized conduction band offset (CBO) in p-Si heterojunction is a major limiting factor for achieving high solar-to-hydrogen efficiency. Herein, we introduced a double CdS/In 2 S 3 ETLs on p-Si to optimize band alignment and facilitate the charge carrier transport at the interface. The p-Si/CdS/In 2 S 3 system presents a step-like energy band alignment and the appropriate CBO at p-Si/CdS (0.46 eV) and CdS/In 2 S 3 (0.25 eV) interface suppress the charge recombination and efficiently extract photogenerated electrons. The Electrochemical impedance spectroscopy measurement shows a lower charge transfer resistance for the double ETLs compared with the single ETL counterparts. As a result, the p-Si/CdS/In 2 S 3 /Pt photoelectrode exhibits a positive onset potential of ∼0.5 V RHE and a high applied bias photo-to-current efficiency of 5.6 % under AM 1.5G illumination. The strategy of band alignment engineering provides an effective way to improve the device performance and can be extended to other emerging semiconductor thin film photocathodes.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
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2019
·Vol. 186
·期 6
·1-8
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IF 5.479
Yalikun Nuerbiya,Mamat Xamxikamar,Li Yongtao,Hu Xun,Wang Ping,Hu Guangzhi
The authors describe a method for synthesis of a nanomaterial consisting of porous carbon encapsulated Mg-Al-Si alloy (denoted as Mg-Al-Si@PC) nanocluster. The nanocluster was synthesis by a solvothermal reaction, followed by high-temperature annealing. The nanoclusters were used as a novel immobilization platform for electrochemical sensing of rutin. The electrochemical behavior of rutin at a modified electrode was investigated by cyclic voltammetry and differential pulse voltammetry. The modified electrode demonstrates a high electrocatalytic activity toward rutin oxidation at a relatively low working potential (0.6 vs. Ag/AgCl). Under optimal conditions, the sensor has a linear response in the 1–10 μM rutin concentration range, and a 0.01 μM lower detection limit (at an S/N ratio of 3). It was successfully applied to the quantification of rutin in pharmaceutical tablets, and satisfactory results were obtained. Furthermore, the results correspond with those with the standard method and with the amounts indicated by the producer, respectively.
Schematic diagram of the Mg-Al-Si@PC nanocluster preparation process and electroanalysis mechanism.
研究领域:
材料科学
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电化学
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纳米技术
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Lunlun Gong,Heng Yin,Chengming Nie,Xuran Sun,Xiuli Wang,Mei Wang
Although hybrid photocathodes built by immobilizing molecular catalysts to the surface of semiconductors through chemical linkages have been reported in recent years, systematic and comparative studies remain scarce about the impact of various anchoring groups on the performance, stability, and charge-transfer kinetics of molecular catalyst-decorated hybrid photocathodes for photoelectrochemical (PEC) H2 production. In this study, the molecular cobaloxime catalysts, CoPy-4-X (Py = pyridine, X = PO3H2, COOH, and CONH(OH)), bearing different anchoring groups were synthesized and covalently immobilized to the surface of the porous TiO2 layer coated on a p-Si plate or a fluorine-doped tin oxide glass. The influence of the anchoring groups on the performance of p-Si/TiO2/CoPy-4-X photocathodes was comparatively studied for PEC H2 evolution. Among the tested hybrid photocathodes, the one with a hydroxamate as an anchoring group displayed higher activity and lower charge-transfer resistance than that observed for the electrode with a carboxylate or a phosphonate as the anchoring group. Notably, the catalytic current of p-Si/TiO2/CoPy-4-CONH(OH) was attenuated only by 2.9% in the controlled potential photoelectrolysis tests in borate buffer solution at pH 9 at 0 V versus a reversible hydrogen electrode over 6 h. Moreover, the influence of anchoring groups on the interfacial electron transfer from the TiO2 layer to the immobilized cobaloxime catalyst and electron–hole recombination was studied by transient absorption spectroscopy. These results revealed that the hydroxamate as an anchoring group is superior to the carboxylate and phosphonate groups for speeding up the interfacial electron transfer and firmly immobilizing the molecular catalysts to the metal oxide semiconductors to build efficient and stable hybrid photoelectrodes.
研究领域:
材料科学
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能源化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Sheng Gong,Yujie Liang,Huilin Gao,Haiyan Liao,Xiaoqiang Lin,Murtaza Hasan,Xinhua Zhou,Sundaram Gunasekaran
Long-term exposure to Fipronil (FIP) roots the vital organ, like liver, kidney, and neurological disorders. Therefore, fast, portable and low-cost sensors are required to detect FIP in environmental and food samples. Here, an electrochemical sensor was successfully developed by using Si-69-β-CD and N-rGO modified a glassy carbon electrode (GCE) for the detection of FIP. The novel Si-69-β-CD composite was prepared by a facile hydrothermal method was subjected to Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), energy dispersive X-ray spectrometers (EDS), powder X-ray diffraction (XRD), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) for morphological and structural confirmation. Results: The electrochemical properties of β-CD were improved by grafting Si-69 as estimated by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The electrochemical studies demonstrated that the developed Si-69-β-CD/N-rGO/GCE sensor exhibited high sensitivity and selectivity for FIP. In addition, under optimized experimental conditions, the Si-69-β-CD/N-rGO/GCE sensor for FIP was shown a wide linear range of 0.01–20 µmol/L and the limit of detection (LOD) of 0.0023 µmol/L. The usefulness of the sensor for the detection of FIP in egg samples was also investigated. Significance: Our study is valueable to the analytical methodology for measurements of Fiproni with a novel method that is robust and sensitive than others. Our current study showed sufficient sensitivity and accuracy and thus is suitable for future application in measuring contaminants in environmental and food samples.
研究领域:
分析化学
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环境科学
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食品科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Bihong Li,Ming Wen,Yijie Ding,Weizhong Zheng,Weizhen Sun,Ling Zhao
The acidity and pore structure of zeolite catalysts play a crucial role in the selectivity and stability of C4 alkylation due to the synergistic effect of reaction activity and diffusion. Herein, the effect of three acidic beta zeolites with different Si/Al ratios on adsorption, diffusion, and catalytic performance was studied using experiments and molecular simulations. The beta zeolite with the lower Si/Al ratio leads to the faster relative diffusion of isobutane to 1-butene and the smaller adsorption amount of alkylate products. Furthermore, the diffusion of molecules in the zigzag channel along the z direction of beta zeolites is much slower than other two directions. The experimental results indicate that lower Si/Al ratio cause the higher content of strong BAS in the zeolite, resulting in the higher hydride activity and the longer catalytic lifetime. This work provides a theoretical basis for the development of high catalytic activity zeolite catalysts.
研究领域:
化学工程
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催化
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材料科学
·
分子模拟
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Xuan Liu,Dian Zhang,Rongrong Ma,Yu Wang,Xiaofeng Yang,Yijun Liu
With the rapid development of hypersonic vehicles and broadband wave-transparent radome, Si 3 N 4 porous ceramics (Si 3 N 4 -PC) have attracted attention due to their excellent intrinsic properties of Si 3 N 4 and high porosity. However, its high porosity results in low strength and toughness, which are fundamental properties for radome. Reaction bonded (RB) Si 3 N 4 -PC has advantages of dielectric properties and cost over general phase transformation sintering (PTS) and sintered reaction bonded (SRB) Si 3 N 4 -PC while it has been neglected in recent years. In this study, RB and SRB Si 3 N 4 -PC prepared by non-aqueous gelcasting and the influence of Si powders ingredient on their properties are discussed in order to illuminate the potential of RB Si 3 N 4 -PC in wave-transparent materials. The results show that RB Si 3 N 4 -PC with dual-granularity ingredients of 5 μm & 45 μm produces a two-tier tissue of framework of coarse whiskers enhanced by a network of tiny whiskers. SRB Si 3 N 4 -PC evolves into a two-tier tissue of framework of columnar and rod-like grains joining together to brace each other. The two-tier microscopic tissue strongly reinforces and toughens the structure and results in higher σ F and γ wof . As a result, the RB and SRB Si 3 N 4 -PC of dual-granularity of 5 μm & 45 μm obtain the maximum σ F of 109.94 MPa and 119.56 MPa as well as maximum γ wof of 990.74 J m -2 and 1167.88 J m -2 , respectively. Furthermore, the ε′ and tanδ of RB and SRB Si 3 N 4 -PC of dual-granularity of 5 μm & 45 μm are about 4.20 and 4.52 as well as 7.01 × 10 -3 and 22.90 × 10 -3 , respectively. It is concluded that RB Si 3 N 4 -PC of dual-granularity has good mechanical and dielectric properties, which are favorable for radome.
研究领域:
材料科学
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陶瓷工程
·
航空航天材料
✓ 已验证
产品关联
DOI
高影响因子
CHEMISTRY OF MATERIALS
·
2020
·
IF 9.567
Huanhuan Jia,Xinmiao Liang,Tao An,Linfeng Peng,Jiwen Feng,Jia Xie
Finding sodium solid electrolytes (SSEs) with good performance is key to building all-solid-state sodium batteries. In the development of solid electrolytes, halogen doping has been shown to be an effective approach. However, it has rarely been applied to chalcogenide-based SSEs, possibly because of strict structure constraints. In this work, the strategy of halogen doping is successfully demonstrated on Na3.67[Sn0.67Si0.33]0.67P0.33S4, a novel SSE with high structural tolerance. The halogen-doped samples formulated as Na3.57[Sn0.67Si0.33]0.67P0.33S3.9X0.1 (X = Cl, Br, and I) exhibit higher ionic conductivities and lower activation energies than the pristine sample. Na3.57[Sn0.67Si0.33]0.67P0.33S3.9I0.1, the I-doped sample, has the highest ambient ionic conductivity of 1.08 mS cm–1 and the lowest activation energy of 0.24 eV. Structure analysis indicates that the high electronegativity of Cl atoms plays an important role in improving the conduction of Na+ ions in Cl-doped samples. The large atomic radius and high polarizability of I are more important factors to accelerate the transportation of Na+ ions in the I-doped counterpart. Furthermore, the all-solid-state sodium batteries assembled with Na3.57[Sn0.67Si0.33]0.67P0.33S3.9I0.1 as solid electrolytes show decent cyclic stability at 30 °C with a current density of 0.15 A g–1. This work systematically manifests the effect of halogen doping in SSEs, providing a versatile method to develop novel SSEs.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
MATERIALS & DESIGN
·
2024
·
IF 7.6
Nana Zhu,Lu Zhu,Baojing Zhang,Peizhong Feng,Shiheng Li,Philipp V. Kiryukhantsev-Korneev,Evgeny A. Levashov,Xuanru Ren,Xiaohong Wang
An innovative two-step approach of self-propagating high-temperature synthesis (SHS) and spark plasma sintering (SPS) was developed to rapidly fabricate MoSi 2 and Mo(Al,Si) 2 ceramics for high-temperature anti-oxidation applications. The SHS process predominantly promoted the synthesis of high-purity and high-yield MoSi 2 and Mo(Si,Al) 2 phases in the alloyed powders. Subsequently, dense and crack-free MoSi 2 and Mo(Al,Si) 2 ceramics were produced using SPS. 1500 °C oxidation tests of the ceramics (100 h) revealed the formation of a protective SiO 2 oxide layer on the surface of MoSi 2 ceramics, while an Al-Si-O composite glassy oxide layer formed on Mo(Si,Al) 2 ceramics, which exhibited better thermal stability and lower oxygen permeability compared to the single SiO 2 oxide layer. However, an excessive Al content (>0.05 at.%) compromised the oxidation resistance due to the emergence of a Si-depleted Mo 5 (Si,Al) 3 layer with inferior oxidation resistance, which was caused by the high-temperature diffusion of Si. Therefore, via this novel two-step SHS-SPS technique compact and crack-free Mo(Si,Al) 2 ceramics can be rapidly synthesized at high temperatures. When trace amount of Al was added (0.05 at.%), Mo(Si 0.95 Al 0.05 ) 2 showed optimum high-temperature oxidation resistance.
研究领域:
材料科学
·
高温结构材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）