Pr6O11 cluster-anchored CoFe-LDH on vertical graphene nanosheets as an oxygen evolution electrocatalyst for long-term high-current-density seawater electrolysis

Abstract

The severe catalyst corrosion caused by chlorides and industrial-scale high current density are two critical issues for seawater electrolysis that need to be solved. Herein, due to the high adsorption energy of Cl and the stabilizing effect of Pr₆O₁₁ on OER active species, our prepared material (named GP/VGSs-CoFe LDH-Pr₆O₁₁) has excellent OER catalytic activity, achieving 2 A cm⁻² at an overpotential of only 466 mV in alkaline seawater. The electrolysis cell NiMoN‖GP/VGSs-CoFe LDH-Pr₆O₁₁ delivers 326 mA cm⁻² and 585 mA cm⁻² at 1.7 V and 1.8 V in alkaline seawater, respectively. With the aid of anti-corrosion agent K₂SO₄, the cell further achieves a long-term stability of 380 h (180 h) at a high current density of 600 mA cm⁻² (1 A cm⁻²) in alkaline seawater. This work provides a new insight into designing non-noble-metal-based catalysts for stable high-current-density seawater electrolysis, which exhibits great potential in large-scale industrial hydrogen production.