Recent advances in electrocatalysts, mechanism, and cell architecture for direct formic acid fuel cells

Abstract

Direct formic acid fuel cells (DFAFCs) are potential candidates as power sources for various applications, especially in portable electronics and medical diagnostic devices. Though they have been the subject of considerable research, commercial prototypes of DFAFCs are rudimentary compared to other liquid fuel cells, particularly the widespread methanol‐based direct methanol fuel cells. Various strategies for rationally engineering the electrocatalysts for enhancing DFAFC performance have been explored in the last few years, such as alloying noble metals with earth‐abundant transition metals, designing specific morphological and structural arrangements, decorating the surface with corrosion‐tolerant cocatalysts, and providing better catalyst support for effective catalyst dispersion. An overall approach may be necessary and should include (i) understanding the underlying mechanism, which will guide the direction of catalyst engineering, (ii) employing morphological, compositional, and structural control of the electrocatalysts to improve catalyst utilization and enhance the intrinsic activity for real‐world applications, and (iii) integrating these in a proficiently designed cell architecture suitable for targeted applications. In this review, we focus on the recent advances in electrocatalysts, formic acid electrooxidation mechanisms, and DFAFC cell architectures, which could help address the opportunities and challenges of commercializing DFAFC as a prospective alternative power source for portable applications.