Seawater splitting for hydrogen production provides a promising pathway for green energy systems. However, the sluggish kinetics, corrosive ions, and the calcareous deposit seriously impede the wide-scale application of seawater electrolysis. Here, we report a trace amount of Cu-mediated anchoring electron-rich Ru centers on metal carbides (Cu-Ru/WC@C) for efficient hydrogen evolution from corrosive seawater. Benefiting from the conductive, electron-loss, and protophilic capacities of Cu atoms, the created Cu-Ru/WC@C catalyst possesses an electron-rich, anti-corrosive, and low oxophilic microenvironments, which eventually delivers excellent hydrogen evolution activities and anti-corrosion properties in seawater electrolysis. It requires a low overpotential of 392 mV to reach 1 A cm(-2) and good long-term stability in alkaline seawater. Notably, the membrane electrolyzer with Cu-Ru/WC@C cathode exhibits outstanding performances for continuous H-2 production under 1.875 V with 250 mA cm(-2). This approach provides essential insights into the seawater corrosion resistance for cathode materials that match the electrochemical hydrogen production industry.

AbstractRuthenium (Ru) has been recognized as a prospective candidate to substitute platinum catalysts in water‐splitting‐based hydrogen production. However, minimizing the Ru contents, optimizing the water dissociation energy of Ru sites, and enhancing the long‐term stability are extremely required, but still face a great challenge. Here, we report on creating tungsten oxide‐anchored Ru clusters (Ru–WOx) with electron‐rich and anti‐corrosive microenvironments for efficient and robust seawater splitting. Benefiting from the abundant oxygen vacancy structure in tungsten oxide support, the Ru–WOx exhibits strong Ru–O and Ru–W bonds at the interface. Our study elucidates that the strong Ru–O bonds in Ru–WOx may accelerate the water dissociation kinetics, and the Ru–W bonds will lead to the strong metal–support interaction and electrons transfer from W to Ru. The optimal Ru–WOx catalysts exhibit a low overpotential of 29 and 218 mV at the current density of 10 mA cm−2 in alkaline and seawater media, respectively. The outstanding long‐term stability discloses that the Ru–WOx catalysts own efficient corrosion resistance in seawater electrolysis. We believe that this work offers new insights into the essential roles of electron‐rich and anti‐corrosive microenvironments in Ru‐based catalysts and provide a new pathway to design efficient and robust cathodes for seawater splitting.

Direct seawater splitting has been considered one of the most promising sustainable approaches for producing green hydrogen. However, the complexity and corrosion of seawater composition still hinder the efficiency, where hydroxide precipitation and sluggish proton supply are the main problems. Catalysts that can simultaneously facilitate proton supply and avoid hydroxide precipitation formation are highly desired. Here, inspired by natural water splitting-related enzyme systems, we report the de novo design of an alkaline-earth-metal (Mg, Ca, and Sr) and ruthenium (Ru) atom co-engineered gradient OH spillover pathway on metal carbides (WC) for efficient and long-lasting direct seawater electrolysis. The fast water dissociation at the Ru and WC interface and gradient OH* transferring local environment created by alkaline metal atoms will retard the formation of insoluble precipitates and provide an efficient proton supply. Consequently, the synthesized C-WC-RuMg catalyst exhibits excellent hydrogen evolution performance in direct seawater with a low overpotential of 180 mV at 10 mA cm-2 and stability for more than 35 h. Meanwhile, similar phenomena can also be observed in C-WC-RuCa and C-WC-RuSr. We anticipate that this study will be crucial for the development of high-performance and powerful cathodes for direct seawater splitting and many other catalysts. Alkaline-earth-metal and Ru atom co-engineered catalysts with a gradient OH spillover pathway on metal carbide have been realized with retard formation of precipitates and efficient proton supply for efficient and long-lasting seawater electrolysis.

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.

A novel, efficient and eco-friendly synthetic strategy for the preparation of thiosulfonates by electrochemical oxidation of thiols is presented. This method enabled thiosulfonates formation under catalyst- and oxidant- free conditions. The electrochemical oxidizing reaction exhibits a good functional group compatibility and broad scope, hence, providing accesses to various disulfides (31 examples) and thiosulfonates (23 examples). The reactions proceeded under simple and mild reaction conditions, and could be scaled up to the gram-scale. They are also applicable in the late-stage synthesis of bioactive molecules.