Nanostructure engineering of ruthenium-modified electrocatalysts for efficient electrocatalytic water splitting

Electrochemical water splitting is a promising and effective strategy for the production of green hydrogen (H2). However, its energy efficiency and large-scale application for industrial requirements are greatly restricted owing to its sluggish reaction kinetics. The utilization of highly efficient noble metal ruthenium (Ru)-based materials is critical for the improvement of water splitting. Considering the high cost and low reserves of metal Ru, the development of efficient approaches to reduce its usage while improving its catalytic performance is essential. Massive efforts have already been devoted to design advanced Ru-modified electrocatalysts by nanostructure engineering and have achieved significant progress in water splitting. Thus, a comprehensive and fundamental summary is urgent but has not previously been reported. In this review, we present a systematic summary of the nanostructure engineering of Ru-modified electrocatalysts for efficient electrocatalytic water splitting. The current reported effective nanostructure strategies are divided into the design of single-atom sites, doping, alloying and heterogeneous interfacial structural engineering. The internal relationship between material structure and catalytic performance and the in-depth catalytic mechanism of Ru-modified electrocatalysts are further discussed, which may be beneficial for the exploitation of other advanced materials for H2 generation by overall water splitting. This review provides a systematic summary of the nanostructure engineering of Ru-modified electrocatalysts for the electrocatalytic water splitting. These regulation strategies, such as single atom sites, doping, alloying and interfacial engineering are summarized in detail.