Kumar Nikhil, Kumar Mukesh, Nagaiah Tharamani C, Siruguri Vasudeva, Rayaprol Sudhindra, Yadav Ashok Kumar, Jha Shambhu Nath, Bhattacharyya Dibyendu, Paul Avijit Kumar
Department of Chemistry , National Institute of Technology Kurukshetra , Kurukshetra 136119 , India.
Department of Chemistry , Indian Institute of Technology Ropar , Rupnagar , Punjab 140001 , India.
ACS Appl Mater Interfaces. 2020 Feb 26;12(8):9190-9200. doi: 10.1021/acsami.9b20199. Epub 2020 Feb 11.
Energy storage and conversion driven by electro- or photocatalyst is a highly exciting field of research, and generations of effective and durable oxide catalysts have received much attention in this field. Here, we report -site lanthanum-doped oxygen-rich quinary oxide CaLaScRuO synthesized by adopting the solid-state reaction method and characterized by various techniques such as powder X-ray diffraction, neutron diffraction, energy-dispersive X-ray spectroscopy, inductively coupled plasma-atomic emission spectrometry, Raman spectroscopy, and temperature-programmed reduction in the presence of a hydrogen atmosphere (H-TPR). X-ray absorption study confirms the existence of mixed valent Ru ions in the structure, which enhances the oxygen stoichiometry for the partial balance of an extra cationic charge. Neutron powder diffraction and reduction of the material in a hydrogen atmosphere (H-TPR) can confirm the oxygen overstoichiometry of the catalyst. The present material works as an efficient and robust oxygen bifunctional electrocatalyst for ORR/OER (oxygen evolution reaction/oxygen reduction reaction) followed by four-electron transfer pathway in a strong (1 M KOH) alkaline medium. The catalytic nature of the designed structural and chemical flexible perovskite is a novel example of an electrocatalyst for the oxygen bifunctional activity.
由电催化剂或光催化剂驱动的能量存储与转换是一个极具吸引力的研究领域，几代有效且耐用的氧化物催化剂在该领域备受关注。在此，我们报道了采用固态反应法合成的 - 位镧掺杂富氧五元氧化物CaLaScRuO，并通过粉末X射线衍射、中子衍射、能量色散X射线光谱、电感耦合等离子体原子发射光谱、拉曼光谱以及在氢气气氛下的程序升温还原（H - TPR）等多种技术对其进行了表征。X射线吸收研究证实了结构中存在混合价态的Ru离子，这增强了氧化学计量比以部分平衡额外的阳离子电荷。中子粉末衍射以及该材料在氢气气氛下的还原（H - TPR）能够证实催化剂的氧超化学计量比。这种材料在强碱性（1 M KOH）介质中作为一种高效且稳定的氧双功能电催化剂，用于ORR/OER（析氧反应/氧还原反应），遵循四电子转移途径。所设计的结构和化学性质灵活的钙钛矿的催化特性是氧双功能活性电催化剂的一个新范例。
