Iron-based heterogeneous catalysts for oxygen evolution reaction; change in perspective from activity promoter to active catalyst

Oxygen evolution reaction is an integral part of energy storage technologies such as metal air batteries, water splitting, and regenerative fuel cells. However, oxygen evolution is 4 electron transfer process that suffers from sluggish reaction kinetics and indolent thermodynamics which mandates the use of a suitable noble metal catalyst. Considering the availability and cost of these precious metal catalysts, development of catalyst based on more abundant metal such as Fe is of vital interest for practical implication of these technologies. In this regards, over past few years several Fe based heterogeneous electrocatalysts are investigated for their electrocatalytic activity. Significant advances in improving the catalytic activity as well as exploring the catalytic mechanism are achieved in this area. Herein, we present an in-depth review on the recent progress in this field. Specific attention is given to design, synthesis, catalytic performance and strategies for improving their performance. A brief overview of existing challenges and future directions in the field of OER catalyst is also summarized.