A Ni-Fe-V trimetallic phosphorus-selenium composite supported on carbon cloth as freestanding electrocatalyst for oxygen evolution reaction

Abstract

Developing highly active non-noble metal oxygen evolution reaction (OER) electrocatalysts is still urgent and significant to enable the large-scale hydrogen production. Herein, we propose a freestanding electrocatalyst of Ni-Fe-V trimetallic phosphorus-selenium composite on carbon cloth (NiV2P/FeSe@CC) for this issue, which is realized by the in-situ growth of V-MOF, the introduction of Ni and Fe components by electrodeposition, and the synchronous phosphatization and selenization treatment. The well-designed composite exhibits an excellent electrical conductivity and multi-level pore structure, which makes for rapid charge/mass transport and sufficient exposure of catalytic sites. The electrochemical deposition process allows Ni and Fe components to be uniformly deposited on the V-MOF, while the phosphorus and selenium co-doping can modulate the catalyst electronic structure and promote the adsorption of reaction intermediates, thus improving the OER catalytic activity. Consequently, the freestanding electrocatalyst exhibits an ultra-low overpotential of 168 mV under a current density of 10 mA cm−2 and a small Tafel slope of 44.32 mV dec-1 in alkaline environment. The outstanding performance is maintained in the integrated electrolyzer, presenting a small voltage of 1.53 V getting a current density of 10 mA cm−2 and an ultrastability for 160 h under 100 mA cm−2.