Facile Route of P‐doped Defect‐rich Manganese‐cobalt Oxide Spinel with Enhanced Oxygen Evolution Reaction Performance. Issue 12 (14th October 2020)

• Record Type: Journal Article
• Authors: Peng, Xiangfeng; Wang, Zhao
• Is Part Of: ChemNanoMat. Volume 6:Issue 12(2020)
• Page Start: 1812
• Page End: 1818
• Publication Date: 2020-10-14
• Subjects: manganese-cobalt spinel -- phosphorus dopant -- defect -- oxygen vacancy -- oxygen evolution reaction; Nanochemistry -- Periodicals; Nanostructured materials -- Periodicals; Nanochemistry; Nanostructured materials; Periodicals; 541.2
• DOI: 10.1002/cnma.202000475
• Languages: English
• ISSNs: 2199-692X

Abstract

Abstract: Phosphorus dopants and defects were successfully introduced to a manganese‐cobalt oxide (MCO) spinel via plasma treatment in the presence of NaH2 PO2 . High‐energy electrons generated by plasma can produce oxygen vacancy and embed phosphorus into the spinel. To balance the charge of lattice phosphorus, manganese and cobalt atoms left their original sites and deposited as MnO and CoP, thereby forming a disordered structure. Meanwhile, the oxidation state of cobalt increased. These changes provided extra active sites for electrochemical reaction and improved electrical conductivity. In addition, tunnels were formed on the surface, thus favoring mass transport in the electrolyte. Compared with pristine MCO, the spinel doped with phosphorus via plasma treatment showed higher oxygen evolution reaction performance, with a lower onset potential of 1.45 V, higher current density of 25.32 mA cm −2 at 1.75 V, and smaller Tafel slope of 118.7 mV dec −1 . These findings can facilitate the development of high‐activity electrocatalysts with dopants and defects for energy storage and conversion systems. Abstract : It's successful to dope phosphorus in manganese‐cobalt oxide spinel for OER by plasma. During the plasma reaction, the phosphorus was doped in spinel and part of metal atoms left their original sites to balance charge. Meanwhile, rich defects were formed and the oxidation state of cobalt increased. It can significantly improve OER performance of electrocatalyst.