Role of UV Plasmonics in the Photocatalytic Performance of TiO₂ Decorated with Aluminum Nanoparticles

We present a facile method, combining sputtering and gas aggregation techniques, to prepare a photocatalytic TiO₂ thin film decorated with stable aluminum plasmonic nanoparticles (Al NPs) to reveal the localized surface plasmon resonance (LSPR) effect on TiO₂ photocatalysis under UV irradiation. We demonstrate for the first time the negative and positive influences of LSPR on UV photocatalysis by irradiating Al NPs/TiO₂ hybrid structures at two different UV wavelengths: both at and above the plasmonic absorption of Al NPs. These findings open the door to design low-cost Al/TiO₂ photocatalytic hybrid surfaces that function in a broad spectral range from deep-ultraviolet to visible wavelengths.