Hydrogen Boride Sheets and Copper Nanoparticle Composites as a Visible‐Light‐Sensitive Hydrogen Release System

Abstract

Hydrogen boride (HB) sheet is a new class of 2D materials comprising hydrogen and boron, synthesized through ion‐exchange and exfoliation techniques. HB sheets can release hydrogen (H2) under light irradiation and is predicted to be a promising H2 storage material. However, its application is limited to the UV region. One approach to enable a visible‐light‐driven system is the utilization of plasmonic metallic nanoparticles. The present study reports H2 release from copper (Cu) nanoparticle‐modified HB sheet (HB/Cu) under visible‐light irradiation. Copper nanoparticles possess unique and strong plasmonic responses in the visible‐light range, making them ideal light absorbers in this system. HB/Cu nanocomposites are synthesized using a simple mixture of copper acetate and HB sheets in acetonitrile, where HB sheets reduced copper ions to metal copper nanoparticles. The photoirradiation results shows that HB/Cu nanocomposites released more H2 than the bare HB sheets under visible‐light irradiation. This is probably due to the plasmonic photothermal effect of copper metal, which enhances H2 generation from the HB sheets. This material offers a viable and cost‐effective approach for developing visible‐light‐sensitive systems.