Enhanced oxygen evolution reaction performance of synergistic effect of TiO2/Ti3C2/FeNi LDH

Abstract The introduction of high-efficiency electrocatalysts can improve the efficiency of oxygen evolution reaction (OER). However, the synergistic effect of elcetrocatalyst and cocatalyst is rarely studied. In this paper, by combining FeNi layered double hydroxide (LDH) electrocatalyst with a two-dimensional (2D) Ti3C2 co-catalyst on TiO2 photocatalyst, the OER performance of TiO2/Ti3C2/FeNi LDH is greatly improved due to the synergistic coupling effect. The microstructure, electrochemical performance and oxygen generation mechanism of TiO2/Ti3C2/FeNi LDH are investigated in this paper. The results showed that the vertical array of FeNi LDH nanosheets created many nanoscale channels for reaction intermediates, enabling them to enter the most active sites on the surface. More importantly, the addition of Ti3C2 with high conductivity greatly effectively improved the charge separation and transfer between TiO2 and FeNi LDH. Therefore, the required over-potential for current density 100 mA/cm2 was only 633 mV for TiO2/2 Ti3C2/FeNi LDH. Meanwhile, Tafel slope was as low as 30 mV/dec with good stability. This work provides a reference for using Ti3C2 as a new type of co-catalyst material to obtain an efficient, stable and economical OER reaction catalyst.