Microwave Synthesis of High Activity FeSe2/C Catalyst toward Oxygen Reduction Reaction

Catalysts

Qiaoling Zheng¹  Xuan Cheng¹  Hengyi Li¹ 

[1]Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005, China

[2] E-Mails:

关键词: fuel cells;    oxygen reduction reaction;    electrocatalytic activity;    iron selenide catalysts;   

DOI  :  10.3390/catal5031079

来源: mdpi

【 摘 要 】

The carbon supported iron selenide catalysts (FeSe₂/C) were prepared with various selenium to iron ratios (Se/Fe), namely, Se/Fe = 2.0, 2.5, 3.0, 3.5 and 4.0, through facile microwave route by using ferrous oxalate (FeC₂O₄·2H₂O) and selenium dioxide (SeO₂) as precursors. Accordingly, effects of Se/Fe ratio on the crystal structure, crystallite size, microstructure, surface composition and electrocatalytic activity for oxygen reduction reaction (ORR) of FeSe₂/C in an alkaline medium were systematically investigated. The results revealed that all the FeSe₂/C catalysts obtained with the Se/Fe ratios of 2.0–4.0 exhibited almost pure orthogonal FeSe₂ structure with the estimated mean crystallite sizes of 32.9–36.2 nm. The electrocatalytic activities in potassium hydroxide solutions were higher than those in perchloric acid solutions, and two peak potentials or two plateaus responded to ORR were observed from cyclic voltammograms and polarization curves, respectively. The ORR potentials of 0.781–0.814 V with the electron transfer numbers of 3.3–3.9 at 0.3 V could be achieved as the Se/Fe ratios varied from 2.0 to 4.0. The Fe and Se were presented at the surface of FeSe₂/C upon further reduction on FeSe₂. The Se/Fe ratios slightly influenced the degree of graphitization in carbon support and the amount of active sites for ORR.

【 授权许可】

CC BY   
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