MATERIALS & DESIGN
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2016
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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
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纳米技术
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电化学
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能源化学
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催化化学
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功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2018
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IF 3.779
Hui Wang,Houzhen Chen,Hongjiao Wang,Lei Wu,Qixing Wu,Zhongkuan Luo,Fang Wang
The electrochemical performance of the lithium−oxygen (Li−O 2 ) batteries largely depends on the material and architecture of the catalytic cathode. In this paper, to avoid the parasitic reactions of carbon and binder with discharge products and reaction intermediates, we proposed an effective design of a free-standing catalytic cathode for Li−O 2 batteries. The FeCo 2 O 4 @Ni electrode consists of FeCo 2 O 4 nanosheets grown directly on nickel (Ni) foam. The resultant hierarchical macroporous/mesoporous structure provides sufficient space for the insoluble discharge product Li 2 O 2 and catalytically active sites for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Consequently, the carbon- and binder-free self-supporting electrode has demonstrated a high discharge capacity with relatively low charge overvoltage and a better cycle performance than the corresponding carbon-based electrodes.
研究领域:
电化学
·
能源材料
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纳米材料
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电催化
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储能技术
✓ 已验证
DOI
高影响因子
Nano Energy
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2020
·
IF 16.602
Qingyan Zhou,Zhen Zhang,Jiajun Cai,Bing Liu,Yunlong Zhang,Xiaofei Gong,Xulei Sui,Aiping Yu,Lei Zhao,Zhenbo Wang,Zhongwei Chen
Rational design and construction of highly efficient and durable non-noble-metal bifunctional catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is crucial to promote the widespread implementation of rechargeable Zn-air batteries. Herein, a bifunctional catalyst comprising Co nanoparticles uniformly embedded in hollow nitrogen doped carbon tubes (Co@hNCTs) is fabricated by a facile tube-directed templating strategy. In this strategy, surfactant-treated polypyrrole (PPy) nanotubes serve as the structure-guiding templates for efficient capture of Co 2+ , realizing the in-situ growth of zeolitic imidazolate frameworks-67 (ZIF-67) nanocrystals on PPy nanotubes . Sodium laurylsulfonate acts as anionic surfactant to endow PPy nanotubes with functional electronegative surface and strong anchoring effect toward ZIF-67, playing the pivotal role in binding of ZIF-67 nanocrystals with PPy nanotubes potently. Consequently, the developed catalyst presents a superior ORR activity with the half-wave potential of 0.87 V excellent durability with only a 7 mV loss of half-wave potential after 5000 cycles. The catalyst also exhibits superior catalytic performance for OER. When serving as an air electrode in Zn-air batteries, a large power density of 149 mW cm −2 and long-term cyclability for over 500 h are realized in ambient air, implying the great potential in practical application.
研究领域:
材料科学
·
电化学
·
能源存储
·
催化化学
·
纳米材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2020
·
IF 10.652
Ranxi Liang,Chaozhu Shu,Anjun Hu,Minglu Li,Zhiqun Ran,Ruixin Zheng,Jianping Long
The sluggish oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) kinetics greatly limit the development of lithium-oxygen (Li-O 2 ) batteries. Therefore, developing efficient electrocatalysts with high stability to boost oxygen involved reactions is particularly important for promoting the application of Li-O 2 batteries. Here, CoSe 2 @NiSe 2 heterostructure with distinct heterogeneous interfaces was fabricated via deliberate interface engineering. The formation of heterogeneous interface promotes local fine atomic array distortion that can act as an additional active site of ORR/OER. In addition, CoSe 2 @NiSe 2 with a distinct heterogeneous interface is favorable for the formation of built-in electric field during charging/discharging to enable electrodes with fast electrical transfer rates and reaction kinetics. Synergistically, the additional active sites brought by the fine atomic array distortion are highly conducive to the reversible formation and decomposition of the product. Undoubtedly, batteries with CoSe 2 @NiSe 2 exhibit excellent discharge/charge capacity (3530.1 mA h g −1 and 3485.6 mA h g −1 ), low overpotential (1.21 V) and excellent electrochemical stability for over 1200 h.
研究领域:
材料科学
·
电化学
·
能源化学
·
纳米催化
·
电池技术
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2019
·
IF 5.162
Bo Lv,Sha Zeng,Wei Yang,Jian Qiao,Chao Zhang,Chengfeng Zhu,Minghai Chen,Jiangtao Di,Qingwen Li
Recently, the development of high-performance bifunctional oxygen catalysts integrated with flexible conductive scaffolds for rechargeable metal-air batteries has attracted considerable interest, driving by fast-growing wearable electronics . Herein, we report a flexible bifunctional oxygen catalyst thin film consisting of Co–N–C bifunctional catalysts embedding in carbon nanotube (CNT) networks. The catalyst is readily prepared by pyrolysis of cobalt-based zeolitic imidazolate frameworks (ZIF-67) that are in-situ synthesized in CNT networks. Such catalyst film demonstrates very high catalytic activities for oxygen reduction (onset potential: 0.91 V, and half-wave potential: 0.87 V vs. RHE) and oxygen evolution (10 mA cm −2 at 1.58 V) reactions, high methanol tolerance property, and long-term stability (97% current retention). Moreover, our integrated catalyst film shows very good structure flexibility and robustness. Based on the obtained film air electrodes, flexible Zn–air batteries demonstrate low charging and discharging overpotentials (0.82 V at 1 mA cm −1 ) and excellent structure stability in the bending tests . These results indicate that presently reported catalyst films are potential air electrodes for flexible metal–air batteries.
研究领域:
材料科学
·
电化学
·
纳米能源
·
先进功能材料
·
可再生能源
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）