PBA-derived Co/CoTe Composite as an Efficient Electrocatalyst for Oxygen Evolution Reaction

초록

Overall water splitting efficiency is closely related to the kinetically sluggish oxygen evolution reaction (OER) [1]. Currently, transition metal-based chalcogenides have attracted a lot of interest as non-precious OER catalysts due to their cost-effectiveness, earth-abundance, and promising catalytic activity [2]. Herein, Prussian blue analogue (PBA)-derived Co/CoTe composite has been fabricated through a reflux-hydrothermal method, followed by hydrogen annealing process and was used as an electrocatalyst for OER. First, CoCo-PBA cubes and Te precursors with hydrazine are converted into CoTe via a reflux-hydrothermal reaction. A subsequent hydrogen annealing process leads to the formation of the unique Co/CoTe heterostructure. The Co/CoTe composite only requires the low overpotentials for OER in alkaline solution. Moreover, excellent catalytic durability is confirmed by long-term chronoamperometric stability tests. The excellent electrocatalytic activity of Co/CoTe composite is mainly originated from the synergistic effect of unique heterostructure system, leading to increase of the electrical conductivity, active electrochemical surface area, and intrinsic catalytic activity.