Deposition of copper indium sulfide on TiO2 nanotube arrays and its application for photocatalytic decomposition of gaseous IPA

Abstract

TiO2 nanotube arrays (TNTs) were modified with copper indium sulfide (Cu/In/S) by successive ionic layer adsorption and reaction (SILAR) method. The field-emission scanning electron microscopy and X-ray photoelectron spectroscopy analysis demonstrated the presence of copper indium sulfide nanoparticles on the surface of the modified TNTs. The Cu/In/S-modified TNTs exhibited higher photocurrent density and photocatalytic activity than plain TNTs. The concentration of sulfur precursor was found to be an important factor on the composition of modified Cu/In/S films by SILAR. Some composition deviations were observed on the stoichiometry of the Cu/In/S-modified TNTs, which evidently affected the electrochemical characteristics of the modified TNTs. Experiments using the modified TNTs of composition close to the stoichiometric ratio of CuInS2 usually delivered higher photocatalytic decomposition of gaseous isopropyl alcohol in air streams and exhibited better stability during operation.

Keywords

• TiO2 nanotube arrays
• Copper indium sulfide
• Successive ionic layer adsorption and reaction (SILAR)
• Photocatalysis