In situ constructing atomic interface in ruthenium-based amorphous hybrid-structure towards solar hydrogen evolution

Abstract

The rational steering and construction of efficient and stable atomic interfaces is highly desirable but rather challenging in solar energy conversion. Here, we report an in-situ oxygen impregnation strategy to build abundant atomic interfaces composed of homogeneous Ru and RuO_x amorphous hybrid-mixture with ultrafast charge transfer, for solar hydrogen evolution with sacrificial agent free. Via in-situ synchrotron X-ray absorption and photoelectron spectroscopies, we can precisely track and identify the gradual formation of atomic interfaces towards homogeneous Ru-RuO_x hybrid-structure at the atomic level. Benefiting from the abundant interfaces, the amorphous RuO_x sites can intrinsically trap the photoexcited hole within an ultrafast process (<100 fs), and the amorphous Ru sites enable subsequent electron transfer (~1.73 ps). Hence, this hybrid-structure triggers long-lived charge-separated states, and results in a high hydrogen evolution rate of 60.8 μmol·h⁻¹. This design integrating the two sites fulfilled each half-reaction in a single hybrid-structure suggests potential guidelines towards efficient artificial photosynthesis.

Solar-driven hydrogen evolution coupled with organic synthesis is important but challenging. Here, the authors report an in-situ oxygen impregnation strategy to build a ruthenium-based amorphous hybrid-mixture with abundant atomic interfaces and show efficient hydrogen evolution with small molecule oxidation.