| dc.description.abstract | Due to the energy crisis and environmental pollution issues, the development of renewable energy is of paramount importance. Hydrogen is regarded as clean energy because it does not produce carbon emissions when burned and hydrogen production through water electrolysis has attracted much attention. However, the hydrogen evolution reaction (HER) at the cathode in alkaline environments is hindered by sluggish kinetics, resulting in higher overpotentials, whereas in acidic environments, the stability of catalysts is a concern. Additionally, given the abundance of seawater resources, producing hydrogen through seawater electrolysis is a sustainable and eco-friendly strategy. Therefore, designing catalysts with high activity and stability is crucial for advancing hydrogen production technologies from both seawater and freshwater.
Ru possesses hydrogen bonding strength comparable to Pt, yet its strong hydrogen adsorption energy necessitates reduction to improve HER performance. Boronization can effectively tune the electronic structure of Ru, aligning it closer to Pt in the volcano plot. In this study, RuB-based catalysts with high noble metal utilization, and high HER activity and stability are synthesized using the NaBH4 reduction method, and the addition of low amounts of Pt not only enhances the catalyst′s activity in 0.5 M H2SO4 electrolytes but also promotes structural stability during long-term test. Additionally, Co improves the catalyst′s hydrolysis ability in alkaline simulated seawater (1 M KOH + 3.5wt% NaCl). Notably, RuB-Pt/C and RuB-CoPt/C exhibit excellent stability and activity in acidic and alkaline simulated seawater electrolytes, with overpotentials of 20 and 15 mV at a current density of 10 mA/cm2, Tafel slopes of 11 and 23 mV dec-1, and mass activities of 7803 and 1194 mA/mgRu+Pt, respectively. Both catalysts maintain superior HER performance after 5000 cycles of stability test.
Additionally, inductively coupled plasma optical emission spectroscopy (ICP-OES) analysis of the electrolytes after ADT reveals that the addition of Co, B, and Pt can effectively prevent or mitigate the dissolution of Ru catalysts in acidic and seawater electrolytes, thereby enhancing the structural stability of catalysts. The stability under acidic conditions is further explored using in-situ X-ray absorption spectroscopy (in-situ XAS), identifying Ru-B as the predominant active site, with Pt addition significantly promoting catalyst structural stability and resulting in exceptional HER performance in acidic electrolytes. Furthermore, CO-stripping test indicates that the addition of Co facilitates seawater dissociation. This study introduces RuB-based catalysts with low noble metal content and high HER performance in both acidic and alkaline simulated seawater electrolytes, shedding light on the mechanisms driving their superior HER performance and providing insights into the development of highly active HER acid and seawater catalysts. | en_US |