Photocatalytic activity of carbon nanotube/Ag3PO4 hybrid from first-principles study

Abstract

Pure silver phosphate (Ag3PO4) is an indirect semiconductor which has super photooxidative capabilities under visible light irradiation. Also, it can be used as a photocatalyst due to the rapid recombination of electron-hole pairs. The low structural stability of pure Ag3PO4 is the major factor militating against its use for practical applications. Under visible light irradiation, carbon nanotubes (CNTs) can increase the stability and photocatalytic activity of Ag3PO4. This study investigated the photocatalytic activity and stability of the CNT (6, 0)/ Ag3PO4 hybrid by analyzing the geometric, electronic and optical properties with the density functional theory method. Semimetallic single-walled carbon nanotubes (SWCNT) (6, 0) may chemically or physically interact with the Ag3PO4 surface depending on its relative orientations. As its surface is exposed by SWCNT (6, 0), Ag3PO4 becomes a direct band gap semiconductor. The small band gap makes the CNT/Ag3PO4 hybrid absorb sunlight from the ultraviolet to the infrared region.