Effect of catalyst layer designs for high-performance and durable anion-exchange membrane water electrolysis

Development of anode design is crucial for highly efficient and durable anion-exchange membrane water electrolysis (AEMWE) as the kinetic of oxygen evolution reaction (OER) is sluggish. In this study, a macroporous catalyst layer (macroporous_CL) was proposed as an anode design for AEMWE to enhance the catalyst utilization. A macroporous_CL contains pores of two main size ranges: hundreds of nanometers and hundreds of micrometers. It is prepared using a spraying method to form nanometer-sized pores. The use of a stainless-steel (SUS) porous transport layer (PTL) as the substrate of the spraying method produces micrometer-sized macropores. In an investigation of the effects of the macroporous_CL and conventional catalyst layer (plain_CL) on AEMWE using two different kinds of oxygen evolution reaction (OER) catalysts, the macroporous_CL exhibited higher performance with lower ohmic and charge-transfer resistances compared to the plain_CL. This performance enhancement was attributed to the improved catalyst utilization and electron transport. Also, the macroporous_CL showed better durability compared to the plain_CL. Therefore, the macroporous_CL has been considered as an alternative anode design for AEMWE. (c) 2022 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

Automated summary

The development of anode design is crucial for efficient and durable anion-exchange membrane water electrolysis (AEMWE) due to slow kinetics of the oxygen evolution reaction (OER). A macroporous catalyst layer (macroporous_CL) is proposed as an alternative anode design for AEMWE to enhance catalyst utilization and electron transport. It has been found that the macroporous_CL exhibits higher performance, lower resistance, and better durability compared to the conventional catalyst layer (plain_CL).