Co2P@NiCo2O4 bi-functional electrocatalyst with low overpotential for water splitting in wide range pH electrolytes

Ying Liu; Fei Yang; Wei Qin; Guowei Yang

doi:10.1016/j.jcis.2018.09.017

Co₂P@NiCo₂O₄ bi-functional electrocatalyst with low overpotential for water splitting in wide range pH electrolytes

J Colloid Interface Sci. 2019 Jan 15:534:55-63. doi: 10.1016/j.jcis.2018.09.017. Epub 2018 Sep 6.

Authors

Ying Liu¹, Fei Yang², Wei Qin², Guowei Yang³

Affiliations

¹ State Key Laboratory of Optoelectronic Materials and Technologies, Nanotechnology Research Center, School of Materials Science & Engineering, Sun Yat-sen University, Guangzhou 510275, Guangdong, People's Republic of China. Electronic address: liuying35@mail.sysu.edu.cn.
² State Key Laboratory of Optoelectronic Materials and Technologies, Nanotechnology Research Center, School of Materials Science & Engineering, Sun Yat-sen University, Guangzhou 510275, Guangdong, People's Republic of China.
³ State Key Laboratory of Optoelectronic Materials and Technologies, Nanotechnology Research Center, School of Materials Science & Engineering, Sun Yat-sen University, Guangzhou 510275, Guangdong, People's Republic of China. Electronic address: stsygw@mail.sysu.edu.cn.

PMID: 30212656
DOI: 10.1016/j.jcis.2018.09.017

Abstract

The Co₂P@NiCo₂O₄ bi-functional electrocatalyst was fabricated for hydrogen evolution reaction and oxygen evolution reaction in acidic, neutral and alkaline media. The Co₂P@NiCo₂O₄ in alkaline media exhibites an extremely low overpotential of 170 mV in oxygen evolution to achieve a current density of 10 mA cm^-2 and produces stable water splitting nearly 30 h. The anchored-Co₂P can enhance the electrochemical performance of pristine NiCo₂O₄ as well as increase the tolerance in acidic media of NiCo₂O₄. Additional, the Co₂P is oxidized to oxides/hydroxides species during the electrocatalytic reaction, which acts as the active centers of the electrocatalysis. The Co₂P@NiCo₂O₄ catalyst can be used as an effective bifunctional synergistic center in a wide range of pH values (from 0 to 14).

Keywords: Bi-functional electrocatalyst; Co(2)P@NiCo(2)O(4); Overpotantial; Oxides/hydroxides species.