Visible-Light Localized Surface Plasmon Resonance of WO3–x Nanosheets and Its Photocatalysis Driven by Plasmonic Hot Carriers

Abstract

Metal oxides are more inexpensive and abundant as plasmonic materials compared with noble metals. This report shows that chemically reduced WO₃–ₓ nanosheets exhibit a localized surface plasmon resonance (LSPR) band centered at 540 nm and photocatalytic activity toward degradation of methyl orange. The methyl orange is decomposed via the reaction with plasmonic hot holes and superoxide radicals from excitation of LSPR. This work has provided evidence that plasmonic hot holes from oxides can directly react with methyl orange and play a significant role in photocatalysis. In contrast, it is well-known that plasmonic hot holes in metals are seldom reported for involvement of photocatalysis.