INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2016
·Vol. 42
·期 4
·2045-2053
·
IF 3.205
Jing-Jia Zhang,Xu-Lei Sui,Lei Zhao,Li-Mei Zhang,Da-Ming Gu,Zhen-Bo Wang
Molybdenum trioxide (MoO 3 ) has been considered an advanced auxiliary support for Pt nanoparticle anchorage due to its excellent activity and stability. Nevertheless, its non-conductivity property still impedes its applications in electrocatalytic fields. Thus, the MoO 3 and carbon composite of a nanostructure is synthesized through sintering process and served as an efficient co-support for Pt-based anode catalyst in this paper. The electrochemical measurements demonstrate that Pt/MoO 3 -C catalyst shows higher catalytic activity and stability than the as-prepared Pt/C. Significantly, it exhibits 1.95 times higher activity and 2.36 times better durability for methanol oxidation when compared with commercial Pt/C. The remarkably enhanced performance of this novel Pt/MoO 3 -C catalyst for methanol electrooxidation can be ascribed to the abundant Pt nucleation active sites, uniformly dispersed Pt nanoparticles and the strong metal-support interaction between Pt and MoO 3 -C. These outstanding properties suggest Pt/MoO 3 -C a promising catalyst for practical application of fuel cell.
研究领域:
电催化
·
纳米材料
·
能源化学
·
燃料电池
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2017
·
IF 6.395
H.R. Jiang,W. Shyy,M.C. Wu,L. Wei,T.S. Zhao
The potential of B 4 C as a metal-free catalyst for vanadium redox reactions is investigated by first-principles calculations. Results show that the central carbon atom of B 4 C can act as a highly active reaction site for redox reactions , due primarily to the abundant unpaired electrons around it. The catalytic effect is then verified experimentally by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) tests, both of which demonstrate that B 4 C nanoparticles can enhance the kinetics for both V 2+ /V 3+ and VO 2+ /VO 2 + redox reactions, indicating a bi-functional effect. The B 4 C-nanoparticle-modified graphite felt electrodes are finally prepared and tested in vanadium redox flow batteries (VRFBs). It is shown that the batteries with the prepared electrodes exhibit energy efficiencies of 88.9% and 80.0% at the current densities of 80 and 160 mA cm −2 , which are 16.6% and 18.8% higher than those with the original graphite felt electrodes. With a further increase in current densities to 240 and 320 mA cm −2 , the batteries can still maintain energy efficiencies of 72.0% and 63.8%, respectively. All these results show that the B 4 C-nanoparticle-modified graphite felt electrode outperforms existing metal-free catalyst modified electrodes , and thus can be promising electrodes for VRFBs.
研究领域:
电化学
·
能源材料
·
催化化学
·
储能技术
·
材料科学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2016
·Vol. 42
·期 7
·3947-3954
·
IF 3.205
Jialei Jin,Yuanzhi Zhu,Yizhe Liu,Yang Li,Wenchao Peng,Guoliang Zhang,Fengbao Zhang,Xiaobin Fan
Producing hydrogen through hydrogen evolution reaction by electrolyzing water is a great alternative to solve the energy crisis and air pollution. Earth abundant transition-metal phosphides, especially CoP , have emerged as promising hydrogen evolution reaction catalysts for recent years. Nowadays, attention is focused on combining CoP with other materials to improve its catalytic activity . Herein, in order to get better hydrogen evolution reaction catalyst, we combined CoP nanoparticles with WS 2 nanosheets. Different CoP to WS 2 mass ratios were set to find the best catalytic activity. CoP/WS 2 composites were prepared through a simple ultrasound induced mixing method. And all the CoP/WS 2 composites have enhanced hydrogen evolution reaction catalytic activity than pure CoP nanoparticles and WS 2 nanosheets. Especially, the optimized CoP/WS 2 composite has the lowest onset overpotential of 50 mV, the largest current density of 78 mA/cm 2 at the overpotential of 300 mV, and the smallest Tafel slope of 64.63 mV/decade, indicating excellent hydrogen evolution reaction catalytic activity.
研究领域:
材料科学
·
电化学
·
纳米催化
·
能源材料
·
无机功能材料
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2016
·Vol. 41
·期 39
·17462-17470
·
IF 3.205
Bing Zhai,Xuezhang Xiao,Wenping Lin,Xu Huang,Xiulin Fan,Shouquan Li,Hongwei Ge,Qidong Wang,Lixin Chen
NbF 5 and eutectic 0.68LiBH 4 –0.32Ca(BH 4 ) 2 were successively infiltrated into highly ordered mesoporous carbon (CMK-3) to obtain a LiBH 4 –Ca(BH 4 ) 2 –NbF 5 @CMK-3 composite. A synergetic effect of nanoconfinement and catalysis on hydrogen desorption properties of the composite was achieved. The onset desorption temperature of LiBH 4 –Ca(BH 4 ) 2 –NbF 5 @CMK-3 is dramatically lower than 120 °C compared with that of as-milled LiBH 4 –Ca(BH 4 ) 2 or LiBH 4 –Ca(BH 4 ) 2 @CMK-3. A hydrogen amount as high as 13.3 wt% can be released within 250 min for LiBH 4 –Ca(BH 4 ) 2 –NbF 5 @CMK-3, compared with only 10.4 wt% for pure LiBH 4 –Ca(BH 4 ) 2 , in which nanoconfinement and catalysis both make some contribution. The cycling hydrogen desorption performance of the composite becomes better likewise due to the addition of NbF 5 . Further microstructure analysis reveals that F − tended to bind with Ca 2+ to form CaF 2 , whereas Nb compound is believed to catalyze the whole system in the form of Nb-based boride (NbB 2 ).
研究领域:
材料科学
·
能源化学
·
纳米科技
·
储氢材料
·
物理化学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2013
·Vol. 38
·期 13
·5251-5258
·
IF 3.548
Qiang Zhao,Zhuobin Yu,Wen Yuan,Jinping Li
Under mild conditions (near-neutral aqueous solutions, room temperature , and atmospheric pressure), an attractive electrolyte was expanded for splitting water and three novel oxygen-evolution catalysts (Co-C i , Ni-C i , Ag-C i ) were generated. The Co-C i catalyst showed a high oxygen-evolution rate (24.42 μmol h −1 ), a low oxygen-evolution overpotential (395 mV) and excellent stability. In addition, the non-amorphous Ag-C i catalyst, different from reported catalyst, was generated. The catalyst has been further characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), and X-ray photoelectron spectroscopy (XPS).
研究领域:
材料化学
·
电化学
·
催化化学
·
能源科学
·
纳米材料
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 85
·69388-69393
·
IF 3.84
Qin Zhou,Shurong Fu,Min Zou,Yiming He,Ying Wu,Tinghua Wu
A magnetic MoO3/Fe3O4 catalyst was prepared and used in the oxidative desulfurization (ODS) of dibenzothiophene (DBT), benzothiophene, and thiophene. The morphology and components of the magnetic composite material were characterized by X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy techniques. Results indicated that MoO3 as an active species was supported on Fe3O4. High calcination temperature leads to the formation of Fe2(MoO4)3 compounds which showed lower activity than MoO3. The highest conversion of 99.5% for ODS of DBT can be achieved on MoO3/Fe3O4 calcinated at 400 °C. In addition, the amount of MoO3/Fe3O4, TBHP/DBT molar ratio and reaction temperature played vital roles in desulfurization efficiency. This work showed the possibility for the utilization of low cost magnetic MoO3/Fe3O4 composite in the oxidative desulfurization because it shows high activity and could be easily separated by applying an external magnetic field, achieving ten times recycling without significant decrease in activity.
研究领域:
催化化学
·
环境化学
·
能源化工
·
材料化学
·
石油炼制
✓ 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
·
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 MOLECULAR CATALYSIS A-CHEMICAL
·
2015
·
IF 3.615
Ze Feng,Yujia Xie,Fang Hao,Pingle Liu,He'an Luo
A series of manganese metalloporphyrins were prepared and tested in cyclohexane oxidation. It has been found that the manganese 5,10,15,20-tetrakis(4-nitrophonyl) porphyrin (Mn-TNPP) presents better catalytic performance. The Mn-TNPP was then immobilized on different supports, and characterized by UV–vis, FT-IR, XRD, TG/DTG and ICP. Among these supported Mn-TNPP catalysts, Mn-TNPP/ZnO exhibits the best selectivity to KA oil and higher turnover number in cyclohexane oxidation. The influence of the reaction conditions and the recycle of the catalysts are discussed. Mn-TNPP/ZnO catalyst presents the average cyclohexane conversion of 7.17%, KA oil selectivity of 91.18%, and the average catalytic turnover number of 6.53 × 10 4 after six times of recycle under 150 °C and 1.0 MPa.
研究领域:
催化化学
·
有机合成
·
工业化学
·
材料化学
·
绿色化学
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2022
·Vol. 43
·期 9
·2443-2452
·
IF 12.92
Yaojia Cheng,Haoqiang Song,Jingkun Yu,Jiangwei Chang,Geoffrey I.N. Waterhouse,Zhiyong Tang,Bai Yang,Siyu Lu
The sluggish kinetics of oxygen reduction reaction (ORR) hinders the commercialization of Zn-air batteries (ZABs). Manipulating the electronic structure of electrocatalysts to optimize the adsorption energy of oxygen-containing intermediates during the 4e − ORR offers a practical route toward improving ORR kinetics. Herein, we designed a novel ORR electrocatalyst containing Co single atoms and nanoparticles supported by carbon dots-derived carbon nanoflowers (Co SAs/NPs CNF). Co SAs/NPs CNF possessed a very high ORR activity ( E 1/2 of the Co SAs/NPs CNF catalyst is 0.83 V ( vs. RHE)), and outstanding catalytic performance and stability when used as the air-electrode catalyst in rechargeable ZABs (152.32 mW cm −2 , 1000.58 mWh g Zn −1 , and over 1300 cycles at a current density of 5 mA cm −2 ). The Co SAs and Co NPs cooperated to improve electron and proton transfer processes during ORR. Theoretical calculations revealed that the presence of adjacent Co NPs optimized the electronic structure of the isolated Co-N 4 sites, significantly lowering the energy barriers for the rate-determining step in ORR (adsorption of *OOH) and thereby delivering outstanding ORR performance. This work reveals that the combination of supported single-atom sites and metal nanoparticles can be highly beneficial for ORR electrocatalysis , outperforming catalysts containing only Co SAs or Co NPs.
研究领域:
电化学
·
纳米材料科学
·
能源化学
·
催化化学
·
先进电池技术
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2020
·
IF 7.216
Xiaojing Jiang,Jianian Chen,Fenglei Lyu,Chen Cheng,Qixuan Zhong,Xuchun Wang,Ayaz Mahsud,Liang Zhang,Qiao Zhang
Controllable fabrication of Fe-N-C based single-atom catalysts (SACs) for enhanced electrocatalytic performance is highly desirable but still challenging. Here, an in situ surface-confined strategy was demonstrated for the synthesis of single atomic Fe-N 4 on N-doped carbon nanoleaves (L-FeNC). The in situ generated Zn 3 [Fe(CN) 6 ] 2 could not only serve as a protection layer against collapse of nanoleaves but also provide abundant Fe source for the formation of Fe-N moieties during pyrolysis, leading to high surface area and high graphitization degree of L-FeNC simultaneously. Benefiting from abundant Fe-N 4 active sites, enhanced mass and charge transfer, the as-prepared L-FeNC manifested a half-wave potential of 0.89 V for oxygen reduction reaction (ORR) in 0.1 M KOH. A maximum power density of 140 mW cm −2 and stable discharge voltage even after operation for 50,000 s have been demonstrated when the L-FeNC was used as air cathode for Zn-air battery. This work not only provided a unique surface-confined strategy for the synthesis of two-dimensional nanocarbons, but also demonstrated the significant benefit from rational design and engineering of Fe-N-C SACs, thus offering great opportunities for fabrication of efficient energy conversion and storage devices.
研究领域:
材料科学
·
电化学
·
能源存储与转换
·
纳米科技
·
催化化学
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2019
·Vol. 27
·期 12
·3053-3059
·
IF 1.911
Nianjun Kang,Dongbo Xu,Weidong Shi
In recent years, the excessive use of antibiotics has become a serious problem for human health. BiVO 4 regarded as one of the most promising visible-light-driven photocatalysts was used to degrade the antibiotics. In this paper, we fabricated Bi/BiVO 4 plasmonic photocatalysts which enhanced the photocatalytic activity of BiVO 4 for degradation of tetracycline (TC) antibiotic. The Bi/BiVO 4 photocatalysts were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy and high-resolution transmission electron microscopy . In addition, the photocatalytic experiment results show that the 0.04-Bi/BiVO 4 sample has the best photocatalytic activity for 2 times than the pure BiVO 4 photocatalyst. The cycle experiments, after four repetitions of the experiments, showed the sample still maintained a high photocatalytic activity. Finally, the photocatalytic reaction mechanism was also studied by free radical capture experiments and electron paramagnetic resonance spectroscopy .
研究领域:
环境化学
·
材料科学
·
光催化
·
纳米材料
·
环境污染治理
·
药物降解
✓ 已验证
DOI
高影响因子
KINETICS AND CATALYSIS
·
2013
·Vol. 54
·期 6
·716-723
·
IF 0.543
Zeng Minfeng,Sun Xudong,Qi Chenze,Zhang Xian-Man
A novel and environmentally friendly heterogeneous catalyst has been prepared through the wet impregnation of copper(I) species onto the highly porous chitosan microspheres (CuI/PCMS). This novel CuI/PCMS heterogeneous catalyst with no additional ligands is much better than CuI homogeneous catalysts when applied in Heck reactions. Moreover, the reaction conditions are much milder than those for the similar copper catalysts mediated cross-coupling reactions reported in the literature. PCMS has been demonstrated not only the excellent solid support, but also have many unique functional groups to chelate the copper (I) species to enhance its catalytic activity.
研究领域:
催化化学
·
有机合成
·
材料化学
·
环境友好化学
·
功能高分子材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）