Recent Progress of Two-Dimensional Metal-Organic Frameworks and Their Derivatives for Oxygen Evolution Electrocatalysis

Abstract

The development of high-performance transition metal−based electrocatalysts for the oxygen evolution reaction (OER) is paramount for electrochemical secondary metal-air batteries and water splitting. Two-dimensional (2D) metal-organic framework (MOF) nanosheets have recently emerged as a novel class of efficient electrocatalysts for OER, due to a high specific surface area, ultrasmall thickness and abundance of active sites. Here, we summarize recent progress in the preparation and characterization of 2D transition metal−based MOFs (e. g. Ni, Co and Cu), as well as their composites and derivatives, including metals/alloys, metal oxides/chalcogenides and metal phosphides/hydroxides, as OER electrocatalysts reported over the past several years. Design principles and preparation routes are presented. The performance of the electrocatalysts is directly compared in terms of overpotential (η) (thermodynamics) and electrocatalytic current density (kinetics), as well as operational stability (economics). Many of these materials exhibit superior catalytic activity compared to the noble metal−based catalysts such as RuO2 (η<300 mV at 10 mA cm−2), and considerable stability with negligible decay with operation over several hours to days. Challenges and perspectives of applying 2D MOFs and their derivatives for OER electrocatalysis are also discussed.