POLYMER SCIENCE SERIES B
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2024
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IF 1
Le Liu,Yang Wentong,Huang Xiaoling,Deng Qingsheng,Yu Deyu,Zhang Hongwen,Jiang Yan
Abstract In this study, VO x was prepared by oxalic acid and vanadium pentoxide under nitrogen atmosphere and SiO 2 was grown on the surface of VO x . Block copolymer (PCL- b -PDMS- b -PCL) was synthesized by hydroxy terminated poly(dimethylsiloxane) and caprolactone, and the composite material containing inorganic particles was obtained by blending VO x /SiO 2 with PCL- b -PDMS- b -PCL. The porous film was constructed by breathing pattern method, and the supersmooth surface was obtained by injecting lubricating oil into the porous film. The composite was tested by Fourier transform infrared spectroscopy, hydrogen NMR spectroscopy, scanning electron microscopy, contact angle and anti-bacterial adhesion. The results showed that PCL- b -PDMS- b -PCL was successfully synthesized, and the prepared composite material containing inorganic particles had excellent superslippery properties after oil injection, and the sliding angle was 2°.
研究领域:
材料科学
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表面工程
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化学合成
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DOI
高影响因子
ACS Catalysis
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2016
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IF 9.307
Gang Liu,Zhi-Jian Zhao,Tengfang Wu,Liang Zeng,Jinlong Gong
Supported VOx catalysts are promising for use in propane dehydrogenation (PDH) because of the relatively superior activity and stable performance upon regeneration. However, the nature of the active sites and reaction mechanism during PDH over VOx-based catalysts remains elusive. We examined active species by attaining various fractions of V5+, V4+, and V3+ ions by adjusting the surface vanadium density on an alumina support. The results reveal a close relationship between TOF and the fraction of V3+ ion, indicating that V3+ was more active for PDH. In situ diffuse reflectance infrared Fourier transform spectroscopy showed the same strong adsorbed species during both propane dehydrogenation and propylene hydrogenation. The results indicated that such an intermediate may correspond to V species containing a C═C bond, i.e., V–C3H5, and a reaction mechanism was proposed accordingly.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2020
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IF 16.683
Yu Gu,Haijun Liu,Miaomiao Yang,Zhipeng Ma,Lianming Zhao,Wei Xing,Pingping Wu,Xinmei Liu,Svetlana Mintova,Peng Bai,Zifeng Yan
The relatively low cost and mild toxicity of vanadium makes it an alternative to commercially applied Pt and Cr based catalysts in propane dehydrogenation (PDH). Conventional VO x /Al 2 O 3 catalyst shows high initial activity, but deactivates fast due to severe coke formation, which requires frequent regeneration by coke combustion and causes massive CO 2 emissions. In this context, we report on the phosphine (PH 3 ) surface modification of VO x /Al 2 O 3 catalyst leading to substantial improvement of its stability. The phosphorus considerably modifies the properties of the VO x /Al 2 O 3 catalyst: (i) tunes surface acidity, (ii) separates polymerized vanadium oxide species and (iii) weakens interaction between vanadium species with alumina support. Synergy among all these factors facilitates desorption of produced propylene and inhibit the oligomerization of coke precursors, which contributed to the enhancement of the catalyst stability during propane dehydrogenation.
研究领域:
化学工程
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催化材料科学
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DOI
高影响因子
ACS Applied Nano Materials
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2023
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IF 5.9
Xiangyang Ji,Yue Ma,Xiao Sun,Shaojia Song,Kun Yang,Weixin Huang,Chunming Xu,Bohan Feng,Jian Liu,Weiyu Song
Propane direct dehydrogenation (PDH) has received much attention. How to effectively catalyze inert C–H bond activation is of great significance for industrial development. Pt-based catalysts show excellent activity but are limited by their expensive price. Cr-based catalysts are scarcely applied owing to their high toxicity. V-based catalysts are appropriate candidates for their cheap price and low toxicity, but they suffer from high energy consumption. The photothermal synergy effect induced by nonradiative relaxation is expected to make the C–H bond activation and hydrogen coupling process easier compared to bare thermal catalysis. Herein, a set of V/TiO2 nanoscale catalysts were synthesized. The optimized 3 wt % V/TiO2 catalyst (hereafter simplified as 3V) has a particle size of ∼26 nm, achieving a propylene production rate of 342 μmol·g–1·h–1 at 500 °C with UV–vis light radiation, which is 9.2% higher compared with bare thermal conditions. In situ radiation X-ray photoelectron spectroscopy (XPS) shows that photon injection leads to more electron-deficient V atoms (Vδ+, 5 > δ > 3). The strengthened Lewis acidity enhances the C3H8 activation as revealed by kinetic evidence and in situ C3H8-DRIFT measurements. The calculated molecular orbital diagrams show that the V atoms decrease the energy gap between the highest occupied orbital (HOMO) of C3H8 and the lowest unoccupied orbital (LUMO) of the model catalyst. This work describes an efficient photothermal synergy approach, specifically the nonthermal effect for promoting propane dehydrogenation.
研究领域:
化学工程
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催化
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材料科学
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DOI
高影响因子
Nanoscale
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2022
·Vol. 14
·期 24
·8640-8648
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IF 8.307
Tao Chen,Changyu Yang,Xuewen Hu,Qicheng Zhang,An Cai,Huibin Liu,Yang Li,Wenchao Peng,Fengbao Zhang,Xiaobin Fan
Aqueous rechargeable zinc-ion batteries (ZIBs) are emerging in grid energy storage due to zinc abundance and intrinsic safety. However, developing suitable cathode materials with satisfactory stability and rate capacity remains a great challenge. Herein, a structure of layered MXene derived nanoporous VOx wrapped with graphene nanosheets (rGO–VOx) is constructed as a cathode for ZIBs. The incorporation of two typical 2D materials imparts composites with shortened diffusion pathways and increased electrical conductivity. Thus, the rGO–VOx cathode exhibits a remarkable rate capability of 196 mA h g−1 at 8 A g−1 and long-term stability with 90% retention after over 1200 cycles at 5 A g−1 in an aqueous coin cell. The Zn storage mechanism is also systematically investigated. The layered V2O5 transforms into layered ZnxV2O5·nH2O with larger interspacing upon cycling. NaV6O15 and the in situ formed ZnxV2O5·nH2O co-contribute to the subsequent insertion and extraction process.
研究领域:
材料科学
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电化学
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DOI
PubMed
高影响因子
Micromachines
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2023
·Vol. 14
·期 10
·1856
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IF 3.4
Qiang Zhang,Xianran Li,Yinyin Zheng,Qian Tu,Shiwen Wei,Hong Shi,Wentao Tang,Liangzhe Chen
As a typical pseudocapacitor material, VOxpossesses mixed valence states, making it an ideal electrode material for symmetric screen-printed supercapacitors. However, its high internal resistance and low energy density are the main hurdles to its widespread application. In this study, a two-dimensional PANI@VOxnanobelt with a core-shell architecture was constructed via a two-step route. This strategy involves the preparation of VOxusing a solvothermal method, and a subsequent in situ polymerization process of the PANI. By virtue of the synergistic effect between the VOxcore and the PANI shell, the optimal VOx@PANI has an enhanced conductivity of 0.7 ± 0.04 S/Ω, which can deliver a high specific capacitance of 347.5 F/g at 0.5 A/g, a decent cycling life of ~72.0%, and an outstanding Coulomb efficiency of ~100% after 5000 cycles at 5 A/g. Moreover, a flexible all-solid-state symmetric supercapacitor (VOx@PANI SSC) with an in-planar interdigitated structure was screen-printed and assembled on a nickel current collector; it yielded a remarkable areal energy density of 115.17 μWh/cm2at an areal power density of 0.39 mW/cm2, and possessed outstanding flexibility and mechanical performance. Notably, a “Xiaomi” hygrothermograph (3.0 V) was powered easily by tandem SSCs with an operating voltage of 3.1 V. Therefore, this advanced pseudocapacitor material with core-shell architecture opens novel ideas for flexible symmetric supercapacitors in powering portable/wearable products.Keywords:VOxnanobelts;PANI;core-shell architecture;flexible;supercapacitor;electronics
研究领域:
材料科学
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能源技术
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产品关联
DOI
PubMed
高影响因子
ACS Catalysis
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2024
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IF 11.3
Hang Yu,Shanjun Mao,Bing Lu,Hao Wang,Xie Zhang,Menghui Qi,Ruiliang Gao,Yong Wang
Multicomponent reactions such as ammoxidation are highly desirable for chemical synthesis. The complicated reaction network and catalytic active sites involved, however, make it rather challenging for extensive structure–performance relationship investigations and subsequent rational design of an efficient catalyst. In this work, efficient VOx/TiO2 catalysts with concise components and exquisite structure design demonstrated 95% selectivity at 98% conversion under 2070 h–1 for 3-picoline ammoxidation. After clarifying that the oxidative dehydrogenation process is rate-limiting, we assumed that the abundance of reactive surface lattice oxygen at the interface of vanadium–titanium is the key to high productivity and suppression of oxidation side reactions since low reaction temperature is beneficial for enlarging the difference in rates of different energy barriers. In addition, rather than applying the traditional neutralization method with alkaline components, in situ formed V2O5 crystallite was subtly to cover the strong acid sites on VOx/TiO2 catalysts in that the strong adsorption of pyridine nitrogen in 3-cyanopyridine on strong acid sites can lead to severe hydrolysis side reactions.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
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2019
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IF 4.507
Lele Jin,Wenzhi Li,Qiying Liu,Longlong Ma,Song Li,Yang Liu,Baikai Zhang,Qi Zhang
The liquid fuel (made of C 5 /C 6 alkanes) was obtained directly from the hydrogenolysis of microcrystalline cellulose (MCC) with Ir-VO x /SiO 2 combined with HZSM-5 as the composite catalyst in a biphasic system (n-dodecane + H 2 O). The performance of the catalyst was investigated by carrying out a series of experiments using various V/Ir molar ratios , catalyst dosages, reaction temperatures, reaction time, hydrogen pressure and substrates. At the optimized conditions, the cellulose was almost completely converted, and at the same time, a high C 5 /C 6 yield of 85.1% was obtained at 210 °C for 24 h and 6 MPa with the V/Ir molar ratio being 0.13. These results not only proved that Ir-VO x /SiO 2 (V/Ir = 0.13) has excellent performance for the hydrogenolysis of MCC to liquid alkanes, but also indicated that vanadium is a good metal promoter for iridium . In addition, it was proven the C5/C6 alkanes were obtained via sorbitol through the combined effect of Ir-VO x /SiO 2 and HZSM-5.
研究领域:
催化化学
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可再生资源转化
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2019
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IF 3.375
Ping Hu,Yan Chen,Xi Yan,Wan-Zhong Lang,Ya-Jun Guo
VOX-SiO2 catalysts have been synthesized by the one-pot method using different vanadium precursors, namely, ammonium metavanadate (NH4VO3; VO3–, V5+), vanadium acetylacetonate [V(acac)3; organic complex, V3+], and vanadyl sulfate (VOSO4; VO2+, V4+). The influence of different vanadium precursors on the structure–performance relationship of these catalysts is studied on the propane dehydrogenation (PDH) reaction. The catalysts derived from VO3– attain a mesoporous structure with fairly high specific surface area and large pore volume, while those prepared with V(acac)3 or VOSO4 display a microporous structure. It is noted that VOX-SiO2 catalysts derived from NH4VO3 present a better catalytic performance, and low-polymerized VOX species display better intrinsic activity compared with isolated species. This study may contribute to the selection of vanadium precursors for the one-pot synthesis.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
ELECTROCHEMISTRY COMMUNICATIONS
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2024
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IF 4.7
Jinru Wen,Hongyan Dan,Chunyang Li,Chunlong Dai,Zifeng Lin
The development of MXenes using Lewis acidic salts for etching (MS-MXenes) in molten salts presents a novel, fluorine-free method attracting considerable interest. However, the behavior of various MS-MXenes and their derivatives in aqueous environments remains largely unexplored. Particularly, vanadium-based MXenes demonstrate intriguing properties in Zn ion aqueous electrolytes. Herein, a fluorine-free V 2 CT x MXene@VO x is synthesized by molten salt etching under an argon atmosphere. The electrochemical properties of V 2 CT x @VO x are tested in various aqueous electrolytes, including Zn(TFSI) 2 , ZnSO 4 , ZnBr 2 , ZnAc 2 , and ZnCl 2 solutions. The V 2 CT x @VO x shows high redox capacities in all these Zn ion electrolytes, with the peak performance observed in 1 M ZnBr 2 , achieving a maximum capacity of 172 mAh g −1 at 1 mV s −1 . This performance rivals that of V 2 CT x MXene prepared through wet-chemical methods. These results underscore the potential of MS-MXenes materials in aqueous energy storage applications.
研究领域:
材料科学
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能源存储技术
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产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2024
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IF 6.5
Jingru Qiu,Guo-Qing Yang,Jiachang Zuo,Xiaoying Liu,Zhipeng Lan,Weikun Chen,Zhong-Wen Liu,Youzhu Yuan
The selective oxidation of methyl glycolate (MG) to methyl glyoxylate (MGO) using molecular oxygen in a fixed-bed reactor represents a greener and more efficient alternative to the traditional batch processing for producing this important fine chemical and intermediate. Despite its potential, detailed understanding of this catalytic reaction is still limited. In our study, VO x / γ -Al 2 O 3 catalysts were identified as effective for the reaction, but their performance strongly depended on the structure of VO x species. The optimal catalyst with nearly monolayer dispersed VO x achieved a high MG conversion of 91% and an MGO selectivity of 71%, alongside maintaining stability for 300 h without noticeable deactivation. At a low V loading of 0.6%, isolated VO x species were formed, exhibiting the highest turnover frequency (TOF) but the lowest MGO selectivity. Increasing the V loading to 3.9% resulted in a blend of less polymeric and isolated VO x species, which decreased the TOF but enhanced MGO selectivity to 59%. With the V loading ranging from 5% to 6.2%, monolayer dispersed VO x became dominant, yielding a lower TOF and the highest MGO selectivity. A further increase in V loading caused the emergence of crystalline V 2 O 5 , which seemed to act as a bystander. Moreover, the redox cycles of V 4+ and V 5+ over the VO x / γ -Al 2 O 3 catalyst played an important role in the selective oxidation of MG to MGO, while the overoxidation of MG to CO 2 might take place through the V 3+ /V 4+ redox pairs, the extent of which was determined by the structure of VO x species. These insights are crucial for developing high-performance VO x -based catalysts for the production of MGO through the selective oxidation of MG.
研究领域:
催化化学
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环境科学
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材料科学
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产品关联
DOI
高影响因子
Processes
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2021
·Vol. 9
·期 1
·119
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IF 2.847
Yu Huang,Shiyue Fang,Mingjiao Tian,Zeyu Jiang,Yani Wu,Chi He
Developing economical and robust catalysts for the highly selective and stable destruction of chlorinated volatile organic compounds (CVOCs) is a great challenge. Here, hollow nanosphere-like VOx/CeO2catalysts with different V/Ce molar ratios were fabricated and adopted for the destruction of1,2–dichloroethane (1,2–DCE). The V0.05Ce catalyst possessed superior catalytic activity, reaction selectivity, and chlorine resistance owing to a large number of oxygen vacancies, excellent low-temperature redox ability, and chemically adsorbed oxygen (O−and O2−) species mobility. Typical chlorinated byproducts (CHCl3, CCl4, C2HCl3,and C2H3Cl3) derived from the cleavage of C–Cl and C–C bonds of 1,2–DCE were detected, which could be effectively inhibited by the abundant acid sites and the strong interactions of VOxspecies with CeO2. The presence of water vapor benefited the activation and deep destruction of 1,2–DCE over V0.05Ce owing to the efficient removal of Cl species from the catalyst surface.Keywords:catalytic destruction;1,2–dichloroethane;VOx/CeO2;chlorinated byproduct inhibition;reaction mechanism
研究领域:
环境科学
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催化化学
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DOI
高影响因子
危险品化学品经营许可证（带存储）