Recent advances of intermetallic nanocatalysts: From structure feature, synthetic control to the enhanced electrocatalytic performance in PEMFCs

Abstract

Nanostructured intermetallic compounds (IMCs) as vital electrocatalysts exhibit remarkable structural advantages in electrocatalysis for proton exchange membrane fuel cells (PEMFCs) due to their distinct ordered atomic structures, well-defined stoichiometry, controllable crystal structures and adjustable electronic properties compared to their disordered counterparts. The exploring function improvements of precisely regulating element composition, lattice strain, and coordination environments, the electronic structure of active sites have been demonstrated to optimize the electrocatalytic performance. In the review, we summarized recent tremendous progress in the synthesis of binary, ternary to high-entropy IMCs nanocrystals with controllable composition, particle sizes and well-defined shapes for PEMFCs application. It is highlighted the synthesis strategies of nanostructural IMCs, focusing on the intrinsic relationship of preparation methods and structural features of the nanostructured IMCs to provide an efficient modulation of atomic configurations as electrocatalysts for potentially further advancements in energy electrocatalysis with the enhanced performance. Subsequently, the state-of-the-art structural characterizations and representative Pt-based IMC catalysts with emphasis on cathodic oxygen reduction reaction and anodic fuel oxidation reaction have been demonstrated with high intrinsic activity, anti-dissolution ability, and long-term durability, making them promising alternatives compared to conventional Pt-based disordered electrocatalysts. Within the conclusion, future research should focus on atomic-level precision synthesis, in-situ characterization, structure-performance relationships and industrial-scale applications to advance intermetallic catalysts further.