Photocatalytic hydrogen production from seawater by TiO2/RuO2 hybrid nanofiber with enhanced light absorption

Abstract

Compared to hydrogen production through pure water photocatalysis, the direct utilization of seawater for hydrogen production aligns better with the principles of sustainable development. Seawater, however, contains impurity ions like Na⁺ and Cl^-, which pose higher demands on photocatalysts. It is widely acknowledged that RuO₂ and TiO₂ demonstrate excellent stability in seawater. Consequently, this study focuses on the model system of RuO₂-modified TiO₂ for investigating hydrogen production in simulated seawater. TiO₂/RuO₂ nanofibers (NFs) were synthesized via a one-step electrospinning method, ensuring intimate contact between the two components. The hydrogen production activity of TiO₂/RuO₂ NFs in simulated seawater nearly matches that in pure water. Remarkably, RuO₂ serves as an oxidation cocatalyst, effectively scavenging holes from the valence band of TiO₂ and enhancing the separation efficiency of electrons and holes. Interestingly, Cl^- ions, similar to RuO₂, contribute to reducing excess holes. This study lays the groundwork for future research into hydrogen production from seawater.

Keywords: Hydrogen production; Photocatalytic; Ruthenium oxide; Seawater; Titanium dioxide.