Laser Ablation Nanoarchitectonics of Au-Cu Alloys Deposited on TiO2 Photocatalyst Films for Switchable Hydrogen Evolution from Formic Acid Dehydrogenation

The regulation of H-2 evolution from formic acid dehydrogenation using recyclable photocatalyst films is an essential approach for on-demand H-2 production. We have successfully generated Au-Cu nanoalloys using a laser ablation method and deposited them on TiO2 photocatalyst films (AuxCu100-x/ TiO2). The Au-Cu/TiO2 films were employed as photocatalysts for H-2 production from formic acid dehydrogenation under light-emitting diode (LED) irradiation (365 nm). The highest H-2 evolution rate for Au20Cu80/TiO2 is archived to 62,500 mu mol h(-1) g(-1) per photocatalyst weight. The remarkable performance of Au20Cu80/TiO2 may account for the formation of Au-rich surfaces and the effect of Au alloying that enables Cu to sustain the metallic form on its surface. The metallic Au-Cu surface on TiO2 is vital to supply the photoexcited electrons of TiO2 to its surface for H-2 evolution. The rate-determining step (RDS) is identified as the reaction of a surface-active species with protons. The results establish a practical preparation of metal alloy deposited on photocatalyst films using laser ablation to develop efficient photocatalysts.

Automated summary

Regulating H-2 production from formic acid dehydrogenation using recyclable photocatalyst films is an important approach. In this study, Au-Cu nanoalloys were successfully prepared and deposited on TiO2 photocatalyst films. The Au-Cu/TiO2 films exhibited high efficiency for H-2 production under LED irradiation. Au20Cu80/TiO2 showed the highest H-2 evolution rate.