title: Highly active electrocatalysis of the hydrogen evolution reaction by cobalt phosphide nanoparticles.
abstract: Nanoparticles of cobalt phosphide, CoP, have been prepared and evaluated as electrocatalysts for the hydrogen evolution reaction (HER) under strongly acidic conditions (0.50 M H2SO4, pH 0.3). Uniform, multi-faceted CoP nanoparticles were synthesized by reacting Co nanoparticles with trioctylphosphine. Electrodes comprised of CoP nanoparticles on a Ti support (2 mg cm(-2) mass loading) produced a cathodic current density of 20 mA cm(-2) at an overpotential of -85 mV. The CoP/Ti electrodes were stable over 24 h of sustained hydrogen production in 0.50 M H2SO4. The activity was essentially unchanged after 400 cyclic voltammetric sweeps, suggesting long-term viability under operating conditions. CoP is therefore amongst the most active, acid-stable, earth-abundant HER electrocatalysts reported to date.
authors.affiliation: Department of Chemistry and Materials Research Institute, The Pennsylvania State University, University Park, PA 16802 (USA).
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Popczun
authors.forename: Carlos G
authors.initials: CG
authors.lastname: Read
authors.forename: Christopher W
authors.initials: CW
authors.lastname: Roske
authors.forename: Nathan S
authors.initials: NS
authors.lastname: Lewis
authors.forename: Raymond E
authors.initials: RE
authors.lastname: Schaak
keywords: electrocatalysis; hydrogen evolution; metal phosphide; nanomaterials; water splitting