Next Generation Noble Metal‐Engineered Catalysts: From Structure Evolution to Structure‐Reactivity Correlation in Water Splitting

Abstract Noble metal‐engineered catalysts (NMECs) play an important role in promoting the practical utilization of water‐splitting devices in hydrogen energy systems. While owing to the complicated catalytic centers, diverse support structures, and changing microenvironments, NMECs still face many challenges when it comes to designing and analyzing the precise catalytic sites and activity‐mechanism analyses, which are crucial for their future developments. Here, this cutting‐edge review systematically discusses recent advancements in designing NMECs for water electrolysis, including the structure evolution, microenvironment modulation, structure‐reactivity correlation, and new horizons. First, the fundamental advantages, mechanisms, and evaluation methods of NMECs for water splitting are outlined. Then, the strategies to modulate the catalytic microenvironments of NMECs are thoroughly summarized, such as crystal phase modulation, alloying effects, crystallization degrees, size effects, and substrate effects. In particular, there are valuable perspectives on bond interactions, theoretical calculations, and evaluation methods to disclose the catalytic mechanisms. Thereafter, a special emphasis is given on structure‐reactivity correlation, performances, and water‐splitting devices. Finally, a thorough discussion of the upcoming difficulties and new directions for developing next‐generation NMECs is presented. It is believed that the review will have a significant influence on creating noble metal‐based catalysts in the field of electrolytic water‐splitting.