CoP nanoparticles embedded in P and N co-doped carbon as efficient bifunctional electrocatalyst for water splitting

• Published in: Journal of energy chemistry Vol. 26; no. 6; pp. 1223 - 1230
• Main Authors: Zhou, Zeqi, Mahmood, Nasir, Zhang, Yongchao, Pan, Lun, Wang, Li, Zhang, Xiangwen, Zou, Ji-Jun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.11.2017
• Subjects: Cobalt phosphide; Electrocatalyst; Hydrogen evolution reaction; Oxygen evolution reaction; Water splitting; Hydrogen evolution reaction; Electrocatalyst; Water splitting; Oxygen evolution reaction; Cobalt phosphide
• ISSN: 2095-4956
• DOI: 10.1016/j.jechem.2017.07.021

Noble-metal-free hydrogen/oxygen evolution reaction（HER/OER） electrocatalysts, especially bifunctional electrocatalysts, are essential for overall water splitting, but their performance is impeded by many factors like poor electrical conductivity. Herein, we fabricated cobalt phosphide（Co P） nanoparticles embedded in P and N co-doped carbon（PNC） matrix（Co P@PNC） to fully realize the high activity of Co P by maximizing its conductivity. Simply a carbonization coupled phosphidation approach was utilized where Co ions and organic ligands of Co-MOF were transferred into Co P and P and N co-doped carbon. The synthesized material shows an ideal electrical conductivity, excellent HER(overpotential of-84 m V and-120 m V @10 m A cm-2 in acidic and alkaline medias, respectively) and OER(overpotential of 330 m V@10 m A cm-2 in alkaline media) performances. Further, Co P@PNC acts as a superior catalyst for both anode and cathode to catalyze overall water splitting and only requires an voltage of 1.52 V to deliver a current density of 10 m A cm-2, superior to the noble-metal catalysts system（Pt/C//IrO2） and the reported noble-metal-free bifunctional electrocatalysts.