Graphitic Carbon Materials with Various Nanostructures Decorated with Fe-N-C Catalytically Active Sites for Air Electrodes
Graphitic Carbon Materials with Various Nanostructures Decorated with Fe-N-C Catalytically Active Sites for Air Electrodes
复制标题
DOI：
10.1007/s12678-022-00716-8
复制
发表时间：
2022-02
期刊：
影响因子：
3.1
通讯作者：
J. Maruyama;Daiki Nakajima;Shohei Maruyama;Shinobu Takenaka;Hirotaka Mizuhata;Akihito Yoshida;M. Kawaguchi
中科院分区：
文献类型：
--
作者：
J. Maruyama;Daiki Nakajima;Shohei Maruyama;Shinobu Takenaka;Hirotaka Mizuhata;Akihito Yoshida;M. Kawaguchi
金属-空气二次电池的空气电极需要具有氧还原反应(ORR)和析氧反应(OER)活性和稳定性的双功能催化剂。一种有前景的催化剂可能是一种含有过渡金属离子与氮配位并嵌入碳表面(金属-N-C中心)作为催化活性中心的碳质材料，尽管此类材料尚未获得足够的活性和稳定性。在这项研究中，系统地研究了纳米结构对双功能催化活性的影响，以了解其活性增强的原因。采用一系列具有不同凹凸纳米结构的石墨炭材料作为衬底，有利于形成稳定的催化剂。在石墨炭表面覆盖了一层含有Fe-N-C位的碳质薄膜，该薄膜是通过铁酞菁升华、沉积在衬底上并分解而成的。观察到ORR和OER活性与纳米结构的明显依赖关系。用表面铁浓度和比表面积解释了这种依赖关系，并提出了OER与凹面结构之间的关系。用Fe-N-C修饰石墨碳材料制备的空气电极的锌空气电池的充放电和循环性能也得到了测试，证实了双功能。我们的研究为从催化剂纳米结构的角度开发活性稳定的双功能催化剂提供了有用的指导。
Active and stable bifunctional catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are required for the air electrode of rechargeable metal-air batteries. A promising catalyst could be a carbonaceous material containing transition metal ions coordinated by nitrogen and embedded in the carbon surface (metal-N–C site) as the catalytically active site, although sufficient activity and stability in such materials have not yet been attained. In this study, a systematic investigation of the effects of nanostructures on bifunctional catalytic activity was carried out to gain insight into the activity enhancement. A series of graphitic carbon materials with various concave and convex nanostructures were used as a substrate, which is advantageous for forming stable catalysts. The graphitic carbon surface was covered with a carbonaceous thin film containing the Fe–N-C site, which was prepared by iron phthalocyanine sublimation, deposition on the substrate, and decomposition. Distinct dependence of the ORR and OER activities on the nanostructures was observed. The dependence was explained by the surface Fe concentration and specific surface area, and the correlation between the OER and the concave structure was also suggested. The charge–discharge and cycling performances of a zinc-air battery with an air electrode prepared from the Fe–N-C-decorated graphitic carbon material were also tested to confirm the bifunctionality. Our study provides a useful guideline for developing active and stable bifunctional catalysts from the viewpoint of the catalyst nanostructure.Graphical abstract