Recent Progress in Bifunctional Electrocatalysts for Overall Water Splitting under Acidic Conditions

• Published in: ChemElectroChem Vol. 6; no. 13; pp. 3244 - 3253
• Main Authors: Jin, Haneul, Joo, Jinwhan, Chaudhari, Nitin K., Choi, Sang‐Il, Lee, Kwangyeol
• Format: Journal Article
• Language: English
• Published: Weinheim John Wiley & Sons, Inc 01.07.2019
• Subjects: acidic media; Acidic water; bifunctional; Catalysis; Catalysts; Chemical process industries; Electrocatalysts; Electrolysis; Electrolytes; Energy conversion; hydrogen evolution reaction; Hydrogen evolution reactions; Hydrogen production; Lifetime; oxygen evolution reaction; Oxygen evolution reactions; Systems design; Water splitting
• ISSN: 2196-0216; 2196-0216
• DOI: 10.1002/celc.201900507

Water electrolysis is an important energy conversion technology used to produce hydrogen on a mass scale. Until now, special emphasis has been placed on technology development for water electrolysis in acidic electrolytes, owing to the more facilitated hydrogen production under acidic conditions compared to alkaline water electrolysis. Among various catalyst design concepts, bifunctional catalysts capable of driving low overpotentials for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are particularly interesting, owing to the simplicity of cell system design and potential capital reduction for catalyst production. Therefore, it is intriguing to prepare bifunctional catalysts that are compatible with acidic electrolytes. In this Minireview, we introduce the recent progress in bifunctional catalysts for overall water electrolysis under acidic conditions. We briefly describe the merits of water electrolysis in acidic solution and summarize the preparation and performance of the state‐of‐the‐art bifunctional catalysts towards both the acidic HER and OER. Finally, perspectives are provided for the current challenges and opportunities for bifunctional catalysts in acidic water electrolysis. Acidic environment: Bifunctional electrocatalysts have emerged as viable candidates for hydrogen production by simplifying cell design and reducing catalyst manufacturing costs. This article reviews recent significant developments of bifunctional electrocatalysts for overall water splitting reactions including the generation of hydrogen and oxygen in acidic conditions.