Enhancing the performance of platinum group metal-based electrocatalysts through nonmetallic element doping

Platinum group metal (PGM) catalysts have been well recognized as one of the best catalysts towards energy conversion and storage devices, such as fuel cells and water electrolyzers. Nevertheless, their commercial applications are strictly limited by the unsatisfactory catalytic activity and stability. Recently, nonmetallic (H, B, C, N, P, S, etc.) atoms doping is explored to be an efficient strategy to optimize the catalytic activity and durability of PGM-based catalysts via precisely electronic and coordination structure modulation, thus arising tremendous attention. However, systematical discussions on this topic is still lacking. In this review, the representative progresses of nonmetal elements doped PGM-based electrocatalysts for different electrocatalytic reactions are summarized. Firstly, this review discusses the key factors that affect the activity and stability of the catalysts, and introduces the basic principles of nonmetal-doping for improving the performance of PGM-based catalysts. Secondly, advanced characterization techniques and theoretical calculations are highlighted respectively for revealing the activity enhancement mechanism. Then the synthesis methods to incorporate the nonmetals are listed, intending to provide inspirations for the future design of materials. The promising modification strategies for tuning the active species are further proposed. Afterwards, an overview of nonmetal-doped PGM-based catalysts is provided for the electrocatalytic applications, with an emphasis on revealing the structure-performance relationship. Finally, further developments and challenges involving synthesis, mechanism analysis, new materials as well as reactions, stability issues and practical applications are outlined, aiming to promote the in-depth research on advanced PGM-based catalysts.