Carbon nanotubes supported Cs-doped NiFe-layered double hydroxide nanosheets as efficient catalyst for oxygen evolution reaction

Abstract

The sluggish kinetics of oxygen evolution reaction (OER) becomes one of the big obstacles for large-scale electrolytic water splitting. It is urgent to develop low-cost and efficient OER catalyst with fast reaction kinetics and low energy barrier. Herein, a novel OER catalyst of carbon nanotubes (CNT) supported cesium-doped NiFe-layered double hydroxide nanosheets (Cs–NiFe-LDH) is synthesized via a facile one-pot solvothermal reaction. The porous Cs–NiFe-LDH@CNT catalyst delivers an ultralow overpotential of 240 mV @10 mA cm−2, a small Tafel slope of 56.22 mV dec−1, and excellent long-term stability. The outstanding catalytic performance is mainly attributed to the synergistic effects of Cs doping and CNT network: the modification of the electronic structure of NiFe-LDH by Cs doping and the conductivity enhancement by CNT network can facilitate the electron transfer and kinetics; the Cs doping and CNT introduction can generate rich active sites; the nanoporous architecture can facilitate the ion diffusion and O2 bubble release. This work provides a synergistic strategy to design and synthesize transition metal based OER catalysts with low-cost, fast kinetics and good stability for water splitting.