Integration of Ag Plasmonic Metal and WO3/InGaN Heterostructure for Photoelectrochemical Water Splitting

In this study, a Ag/WO3/InGaN hybrid heterostructurewas successfully developed by sputtering and molecular beam epitaxytechniques, to obtain unique Ag nanospheres adorned with cauliflower-likeWO(3) nanostructure over the InGaN nanorods (NRs). Exploitingthe localized surface plasmon resonance of Ag, the Ag/WO3/InGaN heterostructure exhibited superior photoabsorption abilityin the visible region (400-700 nm) of the solar spectrum, witha surface plasmon resonance band centered around 440 nm. Comprehensiveanalysis through photoluminescence spectroscopy, photocurrent measurements,and electrochemical impedance spectroscopy revealed that the Ag/WO3/InGaN hybrid heterostructure significantly enhances the chargecarrier separation and transfer kinetics leading to improved overallphotoelectrochemical (PEC) performance. The photocurrent density ofthe Ag/WO3/InGaN photoanode is 1.17 mA/cm(2),which is about 2.72 times higher than that of pure InGaN NRs undervisible light irradiation. The photoanode exhibited excellent stabilityfor about 12 h. From the study, it has been found that the maximumapplied bias photon-to-current efficiency (ABPE) is & SIM;1.67%at the applied bias of 0.6 V. The improved PEC water splitting efficiencyof the Ag/WO3/InGaN photoanode is attributed to the synergisticeffects of localized surface plasmon resonance (LSPR), efficient chargecarrier separation and transport, and the presence of a Schottky junction.Consequently, the plasmonic metal-assisted heterojunction-based semiconductorAg/WO3/InGaN demonstrates immense potential for practicalapplications in photoelectrochemical water splitting.

Automated summary

A Ag/WO3/InGaN hybrid heterostructure was successfully developed, which exhibited superior photoabsorption ability in the visible region. The improved charge carrier separation and transfer kinetics lead to enhanced overall photoelectrochemical performance.