Preparation of a colloidal array of NaTaO3nanoparticlesvia a confined space synthesis route and its photocatalytic application

Abstract

The confined space synthesis method has been applied to the preparation of sodium tantalate (NaTaO₃); hydrothermal reaction of NaOH and Ta₂O₅ was carried out in the pores of a three-dimensional mesoporous carbon, which was replicated by the colloidal array of silica nanospheres (SNSs) 20 nm in size. This approach led to the formation of a colloidal array of NaTaO₃ nanoparticles 20 nm in size with a surface area of 34 m² g⁻¹. The photocatalytic performance of the colloidal array of NaTaO₃ nanoparticles for overall water splitting under UV irradiation (λ > 200 nm) was evaluated after loading a NiO cocatalyst onto NaTaO₃ samples. The NiO-loaded NaTaO₃ nanoparticles showed photocatalytic activity for overall water splitting more than three times as high as non-structured bulk NaTaO₃ particles.