Elucidating the Pulsed Laser Deposition Process of BiVO4 Photoelectrodes for Solar Water Splitting

Moritz Kölbach,Karsten Harbauer,Klaus Ellmer,Roel Van De Krol

doi:10.1021/acs.jpcc.9b11265

Abstract

BiVO4 thin films for use as photoelectrodes for solar water splitting are prepared by pulsed laser deposition (PLD), a powerful technique to synthesize compact multinary metal oxide films with high...

Highlights

The generation of hydrogen by solar-driven water splitting could become a key technology in future sustainable energy scenarios.[1]
To minimize the concentration of detrimental electronic defects in BiVO4 films made by pulsed laser deposition (PLD), deviations from the ideal stoichiometry should be avoided.[3]
The cation stoichiometry in the films depends on several process parameters, the most important of which are the laser fluence, the oxygen background pressure, and the substrate temperature.[27,28]

Summary

■ INTRODUCTION

The generation of hydrogen by solar-driven water splitting could become a key technology in future sustainable energy scenarios.[1]. Ionized by the laser, the ablated species form a luminous plasma plume that rapidly expands away from the target surface, after which they are collected on a substrate This ion-assisted deposition process allows the formation of compact and dense films due to the high kinetic energy of the ablated species and the pulsed nature of the deposition. The short laser pulses (∼25 ns) result in supersaturation of the species that arrive at the substrate surface This leads to the formation of a large number of nucleation sites and thereby promotes a uniform, layer-bylayer growth of the film.[22,23] Being a vacuum-based deposition technique, PLD makes it easy to work with high-purity target materials compared to solution-based thin-film processes such as spray pyrolysis.

■ RESULTS AND DISCUSSION

■ CONCLUSIONS

■ ACKNOWLEDGMENTS

■ REFERENCES