Structural, optical properties of ZnO doped SnO2 nanocomposites with enhanced photocatalytic performance under UV illumination

Abstract

ZnO doped SnO2 nanocrystallites are fabricated by the sol-gel technique in the existence of polyethylene glycol as a template and characterized by various techniques for structural, morphological and optical properties. The photocatalytic efficiency of the synthesized photocatalysts is assessed by photodegradation of methylene blue dye under ultraviolet light illumination. The ZnO/SnO2 molar ratios are changed in order to study their effect on the photocatalytic efficiency. The ZnO/SnO2 nanocrystallites are a most efficient photocatalyst with the efficiency of 1.0:1.0 in molar ratio and it is attributed to the existence of heterojunctions between the ZnO and SnO2. This allows increased charge parting of the photogenerated electron/hole pairs due to the energy difference amongst the two oxides.