title: Urchin-like CoP Nanocrystals as Hydrogen Evolution Reaction and Oxygen Reduction Reaction Dual-Electrocatalyst with Superior Stability.
abstract: High-performance electrocatalysts with superior stability are critically important for their practical applications in hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR). Herein, we report a facile method to fabricate urchin-like CoP nanocrystals (NCs) as catalyst for both HER and ORR with desirable electrocatalytic activities and long-term stability. The urchin-like CoP NCs with a diameter of 5 μm were successfully prepared by a hydrothermal reaction following a phosphidation treatment in N2 atmosphere and present excellent HER catalytic performance with a low onset overpotential of 50 mV, a small Tafel slope of 46 mV/decade, and an exceptional low overpotential of ~180 mV at a current density of 100 mA cm(-2) with a mass loading density of 0.28 mg/cm(2). Meanwhile, a remarkable ORR catalytic activity was observed with a half-potential of 0.7 V and an onset potential of 0.8 V at 1600 rpm and a scan rate of 5 mV s(-1). More importantly, the urchin-like CoP NCs present superior stability and keep their catalytic activity for at least 10 000 CV cycles for HER in 0.5 M H2SO4 and over 30 000 s for ORR in 0.1 M KOH, which is ascribed to their robust three-dimensional structure. This urchin-like CoP NCs might be a promising replacement to the Pt-based electrocatalysts in water splitting and fuel cells.
authors.affiliation: Key Laboratory of Nano-Bio Interface, Division of Nanobiomedicine and i-Lab, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences , Suzhou 215123, China.
authors.forename: Hongchao
authors.initials: H
authors.lastname: Yang
authors.affiliation: Key Laboratory of Nano-Bio Interface, Division of Nanobiomedicine and i-Lab, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences , Suzhou 215123, China.
authors.forename: Yejun
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Nano-Bio Interface, Division of Nanobiomedicine and i-Lab, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences , Suzhou 215123, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Hu
authors.affiliation: Key Laboratory of Nano-Bio Interface, Division of Nanobiomedicine and i-Lab, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences , Suzhou 215123, China.
authors.forename: Qiangbin
authors.initials: Q
authors.lastname: Wang
keywords: Cobalt phosphide; durability; electrocatalyst; hydrogen evolution reaction; oxygen reduction reaction