Recent advances in layered double hydroxide electrocatalysts for the oxygen evolution reaction

The energy consumption of hydrogen production from electrolytic water splitting originates from the oxygen evolution reaction (OER). Development of efficient and cost-effective OER electrocatalysts has become a high-priority research task. In this regard, layered double hydroxides (LDHs) as one of the promising OER electrocatalysts have been intensely researched due to their unique 2D layered structure and excellent physicochemical properties. Herein, this review aims to summarize recent strategies to design LDHs, including nanostructuring, hybrid LDHs with conductive materials, partial substitution of cations, interlayer anion replacement, vacancy creation, and combination of computational methods and operando techniques. Specifically, a thorough literature overview in the developments of LDHs to improve OER performance is appraised in detail, based on the compositional difference of transition metal components. Challenges and future directions in designing LDHs as OER electrocatalysts are discussed. The provided discussion will be favorable to explore and develop better catalysts and device units for practical applications and will offer a basic understanding of the OER process along with key issues to evaluate the performance.