Ultrathin CNTs@FeOOH nanoflake core/shell networks as efficient electrocatalysts for the oxygen evolution reaction

Transition metal (oxy)hydroxides are a class of promising non-noble metal based electrocatalysts utilized for the water oxidation reaction but suffer from poor electrical conductivity. Herein, we report on CNTs@ultrathin FeOOH nanoflake core/shell networks on a carbon cloth (CNTs@FeOOH/CC) for the oxygen evolution reaction (OER). With the assistance of a layer of ZnO formed via atomic layer deposition (ALD), ultrathin FeOOH nanoflakes are uniformly grown on CNTs. The CNT cores serve as highly conductive channels to facilitate the transfer of electrons, which effectively enhances the electrical conductivity of FeOOH. Furthermore, the interwoven network structure increases the mass loading and utilization of FeOOH. As a result, the CNTs@FeOOH/CC catalyst exhibits a high OER performance, with features such as a low onset overpotential, large anodic current density, small Tafel slope and excellent long-term electrolysis durability, which are highly desirable for a promising OER electrocatalyst.