ACS Sustainable Chemistry & Engineering
·
2020
·
IF 7.632
Yanyan Gao,Ming Hou,Liang He,Manman Qi,Haiping Chen,Wenzhe luo,Zhigang Shao
To enhance the performance and durability of proton-exchange membrane fuel cells (PEMFCs), we looked beyond the polymer-skeleton electrospinning electrode and developed a novel carbon-skeleton nanofiber electrode (the C-spun electrode) by a facile heat-treatment process. After thermal annealing at 600 °C, part of the disordered Pt3Co nanoparticles converted into an ordered intermetallic phase, with an apparently improved oxygen reduction reaction (ORR) activity (E1/2 increased by 50 mV). Meanwhile, the polymers in the polymer-skeleton nanofibers were carbonized and transformed into carbon skeletons, which exhibited excellent corrosion resistance during extensive carbon corrosion testings (1.0–1.5 V, 0.5 V s–1, 1600 rpm, 30 000 cycles). In unit-cell tests, the C-spun electrode achieved an excellent performance of 8.207 W mgPt–1 (H2/air, 80 °C, 1 bar, 100% RH), which is higher than that of the previously reported electrodes with commercial Pt3Co/C. After 50 000 potential scanning cycles, a negligible performance loss was observed. The C-spun electrode provides a new direction for the next-generation electrodes of PEMFCs.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2024
·
IF 5.4
Mingjie Xu,Ye Xiao,Tianli Liu,Hailong Wang,Bingbing Fan,Yanhao Dong,Chang-An Wang
Proton exchange membrane fuel cells (PEMFCs) have received extensive attention in electric vehicles and drones because of their high energy and power density. However, the performance of the PEMFCs is limited by the slow kinetic process of cathodic oxygen reduction. It is necessary to develop efficient catalysts with a low cost, high activity, and good electrochemical stability. Pt–M (M = Fe, Co, Ni, Cu, etc.) alloy catalysts are among the top candidates. The lattice of Pt shrinks when charge transfer from M to Pt occurs, which lowers the energy of the d-band of Pt. It not only balances the adsorption and desorption energies of oxygen-containing intermediates but also improves the stability of catalytic sites. In this study, we report a Pt3Co alloy catalyst supported on a N-doped carbon supports. The catalyst exhibits excellent ORR activity and outstanding durability performance as compared with the commercial JM Pt/C catalyst. The half-wave potential before and after accelerated durability testing is more positive, and the mass activity and the specific activity are much higher than the commercial Pt/C in both 0.1 M KOH and 0.1 M HClO4. Besides, the hydrogen evolution reaction performance has also been significantly improved compared to the Pt/C catalyst. This method is simple and feasible, which offers a strategy for the synthesis of high-performance electrocatalysts for PEMFCs.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
IONICS
·
2021
·Vol. 27
·期 6
·2553-2560
·
IF 2.817
Cheng Zhenzhi,Liao Sen,Zhou Weiping,Luo Guangsheng,Huang Haifu
We developed a solid phase method to fabricate structurally ordered Pt 3 Co/C nanoparticles (NPs) with controllable component proportion as a high efficiency catalyst toward oxygen-reduction reaction. As a result, Pt 3 Co/C NPs exhibit high crystallinity with small average size and narrow size distribution. Moreover, the ordered Pt 3 Co/C NPs own enhanced ORR catalytic performance in acid. During the preparation process, the NaCl-matrix acts synergistically with carbon black as nanoreactors for Pt alloying with Co, avoiding serious sintering resulted by annealing at high temperature. Furthermore, other Pt-based NPs supported on carbon can also be prepared by this methodology.
研究领域:
材料科学
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电化学
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2022
·
IF 6.959
Jie-wen Liu,Jian Zhang,Ming-jie Xu,Chuan-jin Tian,Xiao-jun Zeng,Chang-an Wang
Developing highly active and reliable Pt-based catalysts is a major challenge for the widespread commercialization of proton-exchange membrane fuel cells. Herein, we have designed Pt3Co@C hollow sphere catalysts by the template method, in which PtCo alloy nanoparticles of approximately 3 nm diameter are anchored in a porous shell of nitrogen-doped carbon hollow spheres. Due to the confinement effect of the porous carbon shell, PtCo alloy nanoparticles possess excellent resistance to sintering, maintaining 2–3 nm size after calcination at 800 °C. Also, Pt3Co@C hollow sphere catalysts exhibit superior catalytic activity and stability in the oxygen reduction reaction, achieving 3.6 times the mass activity of the corresponding commercial Pt/C catalyst. Such catalysts with a mass activity retention rate of 87% after accelerated durability testing and no significant decay in activity after 10,000 potential cycles. Meanwhile, Pt3Co@C catalysts exhibit extremely high catalytic activity and surprising durability for the hydrogen evolution reaction process over the entire pH range. We believe that this methodology provides an insight into the preparation of high-performance electrocatalysts.
研究领域:
材料科学
·
电化学
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2024
·
IF 5.4
Mingjie Xu,Ye Xiao,Jingxi Zhang,Yuting Xia,Tianli Liu,Yanhao Dong,Chang-An Wang
Pt-based alloys are important catalysts in fuel cells, especially for the oxygen reduction reaction (ORR). A key problem to be addressed is to develop high-activity ORR catalysts with low Pt loading or, equivalently, to increase the catalytic activity per Pt amount. Here, we report a Pt–Co alloy catalyst with Pt-enriched skin and a Pt–Co core structure via microwave activation and ethylene glycol reduction. The synthesis route is efficient and controllable, resulting in highly active catalysts with a fine particle size and narrow size distribution. The synthesized catalysts show significant advantages in ORR activity compared to commercial catalysts. We proposed that the improved activity and stability are due to a Pt-enriched surface of the Pt3Co catalysts, and such a surface structure is dynamically formed via selective etching of Co during nonequilibrium synthesis under the harsh environment of acid, ethylene glycol reduction, and microwave treatment.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）