摘要
开发新型的非贵金属氧还原催化剂是阴离子膜燃料电池的研究热点之一。本文采用自组装法制备了g-C_3N_4/WO_3(H_2O)_(0.33)氧还原催化剂,利用X射线衍射(XRD)、场发射电子扫描显微镜(FE-SEM)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)对其形貌和结构进行表征,并通过电化学方法评价了其催化氧还原性能。结果表明,利用g-C_3N_4杂化WO_3(H_2O)_(0.33)可提高其氧还原活性。第一性原理的计算结果证实,由于g-C_3N_4具有共轭π键结构,WO_3(H_2O)_(0.33)d层电子与π*电子形成的导电能带为电子的转移提供了有效通道,从而提升其催化剂活性。
The development of non-precious metal oxygen reduction catalysts which used in Anion exchange membrane fuel cell(AMFC) is the research hotspot of new energy technology. In this works, g-C_3N_4/WO_3(H_2O)_(0.33) were synthesized by self-assembly methods. The samples were evidently investigated by X-ray diffraction(XRD), field emission on scanning electron microscopy(FE-SEM), transmission electron microscopy(TEM) and X-ray photo-electron spectroscopy(XPS). The oxygen reduction reaction(ORR) activity of catalysts was tested by electrochemical methods. Result shows that the g-C_3N_4/WO_3(H_2O)_(0.33) presented a significantly enhanced ORR performance than WO_3(H_2O)_(0.33). The calculated results from the first principles revealed the mechanisms of g-C_3N_4 enhancing the ORR performance of WO_3(H_2O)_(0.33). g-C_3N_4 as a π-conjugated material can form d-π* bond with d orbital of WO_3(H_2O)_(0.33). This new bond can provide an effective way for electronic transmissions resulted in the enhancement of ORR performance.
引文
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