Industry-applicable, efficient hydrogen evolution reaction through an interface-activated bimetallic electrode with seawater photolysis in alkaline media
<p><a><b>Hydrogen evolution reaction (HER) electrocatalysts over platinum (Pt) in an alkaline medium is crucial for hydrogen economy. Herein, we demonstrate new concept “interface-active electrode” to transform naturally inert alkaline HER materials towards industry-applicable HER electrocatalyst, comprised of interface-rich NiP<sub>2</sub>-FeP<sub>2</sub> on Cu nanowires that required overpotential as low as 23.6 and 357 mV at -10 and -1000 mA/cm<sup>2</sup>, respectively, with exceptional stability at the industrial current density of -1 A cm<sup>-2</sup>, superior to commercial Pt under alkaline solution. Structural characterization and theoretical calculations revealed the abundant interface between facets of NiP<sub>2</sub>-FeP<sub>2 </sub>on Cu exhibits optimum H adsorption-free energy than Pt and lower kinetic barrier for water dissociation (Δ<i>G</i><sub>B</sub> = 0.16 eV), boosting alkaline HER. Additionally, when integrated in a water splitting device, generated 10 mA/cm<sup>2 </sup>at only </b></a><b>1.42, 1.4, and 1.31 V </b><b>under 1 M KOH, artificial seawater at 25 ̊C and 100 ̊C, respectively, along with high solar-to-hydrogen (STH) conversion efficiency of 19.85</b><b> %. </b></p>