Catalysts
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2018
·Vol. 8
·期 2
·53
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IF 3.465
Yuanyuan Zhao,Ya Chu,Xiuping Ju,Jinsheng Zhao,Lingqian Kong,Yan Zhang
In this work, a nitrogen-containing bidentate ligand named 5,5′-(9-octyl-9H-carbazole-2,7-diyl)bis(1,10-phenanthroline) (OCBP) was synthesized as a nitrogen precursor for making an oxygen reduction catalyst. The 1,10-phenanthroline unit provides a coordination site for copper ions, and the resulting Cu-Nxunit may be responsible for the catalytic activities of the catalyst. Carbon black was selected as a support to improve the electroconductibility of the resulting catalyst. The metallo-supramolecule (Cu-SOCBP) was dispersed on the surface of Vulcan XC-72 carbon and was used as a catalyst (designated as Cu-SOCBP/C) for the oxygen reduction reaction (ORR). The microscope structure and surface components of the catalyst were acquired via scanning electron microscopy and X-ray photoelectron spectroscopy, as well as X-ray powder diffraction. The electrochemical property and ORR mechanism of Cu-SOCBP/C were analyzed using a variety of electroanalytical methods including cyclic voltammetry, electrochemical impedance spectroscopy, and linear sweep voltammetry. These results show that Cu-SOCBP/C was successfully synthesized and that ORR was achieved mainly via a four-electron transfer process to water. Thus, Cu-SOCBP/C was an effective catalyst and might have potential application as a cathodic catalyst in microbial fuel cells, which operate in an aqueous medium.Keywords:supramolecule;ORR activity;kinetics study
研究领域:
电化学
·
材料科学
✓ 已验证
DOI
高影响因子
Industrial Chemistry & Materials
·
2024
·
IF 0
Jiayao Cui,Junyong Min,Hao Wang,Jianglan Shui,Lishan Peng,Zhenye Kang,Jieyuan Liu,Qingjun Chen,Shuo Bai,Yanrong Liu
Developing single-atom Fe–N4/C catalysts is crucial for the large-scale implementation of proton exchange membrane fuel cells (PEMFCs). While Fe–N4/C catalysts are inherently active in accelerating the slow ORR process, their performance is still inferior to that of Pt/C. Herein, a trace Co-doped Fe single-atom catalyst (Fe(tCo)–N–C) containing more active Fe2N8 sites has been synthesized. Interestingly, compared with typical FeN4 sites in an Fe–N–C electrocatalyst, the Fe2N8 sites generate a larger Fe–N bond length due to Co-doping. The elongated Fe–N bond in Fe2N8 lowers the d-band center and charge density of iron sites, enhancing the ORR process by facilitating the formation of *OOH and generation and desorption of *OH. Fe(tCo)–N–C manifested excellent acidic and alkaline ORR activity, with a half-wave potential (E1/2) of 0.80 V in HClO4 solution and 0.89 V in KOH medium. More importantly, high peak power densities (Pmax) were realized by applying Fe(tCo)–N–C in PEMFCs, with the Pmax reaching 890 mW cm−2 in H2–O2 and 380 mW cm−2 in H2–air. Additionally, trace Co dopants in the catalyst improved carbon graphitization and provided high ORR catalytic stability. This research introduces an innovative approach to engineering highly active Fe2N8 sites, providing valuable insights for the sustainable progress of PEMFC technology.
研究领域:
电化学
·
催化
·
能源材料
·
燃料电池
·
纳米技术
✓ 已验证
DOI
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Shujie Xue,Rongzhong Yang,Cong Lei,Jianan Zhao,Shanshan Sun,Minglin Zhao,Zhaogen Wang,Qinghong Huang,Yuping Wu
Pt-based nanocatalysts supported on carbon materials have exhibited remarkable catalytic activity in the oxygen reduction reaction (ORR). However, these catalysts still encounter challenges such as low utilization efficiency, weak binding strength with substrate and proneness to detachment from it. Consequently, we explore the potential application of electron-rich polymer as carrier in high efficiency ORR catalysts, the uniformly distributed Pt-PANI catalyst is successfully synthesized by taking advantage of ion-exchange property of polyaniline (PANI). As an emerging catalyst for ORR, Pt-PANI shows excellent ORR performance in acidic solution, the vertically aligned PANI nanoarrays accelerate the ion diffusion in electrolyte and promote the charge transfer at the interface, improving the catalytic activity of low-loading Pt-based catalyst. In short, this work provides a novel alternative beyond conventional carbonaceous materials for the selection of carriers for Pt-based catalyst.
研究领域:
材料科学
·
电化学
·
催化
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2024
·
IF 20.2
Zhipeng Liu,Heping Xie,Yuan Zhang,Junbiao Li,Junda You,Hongxin Yang,Haojie Zhu,Meng Ni,Zongping Shao,Bin Chen
To guarantee the efficient and durable operation of oxygen ion/proton-conducting ceramic fuel cells , the cathode materials need to be versatile in terms of high activity, good CO 2 resistance, and matched thermal expansion behavior with electrolyte, etc. In this study, we substituted 10% Nb to the B-site of parent perovskite-BaCo 0.7 Fe 0.2 Y 0.1 O 3-δ , to form a single-phase material with triple conducting (H + /O 2- /e - ) capability as a highly ORR-active cathode. The doped BaCo 0.6 Fe 0.2 Y 0.1 Nb 0.1 O 3-δ (BCFYN) shows promising ORR activity due to the optimized oxygen vacancy , improved hydration capacity, and accelerated charge transfer kinetics. The reduction of thermal expansion coefficient (TEC) and enhanced CO 2 resistance also facilitate the cathode durability. As a result, the area-specific resistances of BCFYN electrode at 550 °C for oxygen-ion and proton conducting symmetrical cells were only 0.106 and 0.24 Ω cm 2 , respectively. These results indicate that BCFYN is a highly promising cathode material for both SOFCs and PCFCs.
研究领域:
材料科学
·
能源工程
·
电化学
·
燃料电池技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）