Hydrothermal assisted synthesis and structural characterization of Zn doped SnO2 nanoparticles for catalytic reduction of 4-nitrophenol

Abstract

Monophasic pristine and 1 to 5 mol% Zn-doped SnO2 nanoparticles have been hydrothermally synthesized for catalytic reduction of 4-nitrophenol to 4-aminophenol. X-ray diffraction analysis confirms the formation of tetragonal crystal structure and successful doping of Zn over SnO2. The particle size and morphologies of as-synthesized nanoparticles was confirmed by transmission and scanning electron microscopic studies. Band gap variation with Zn doping was analysed with UV–visible diffused reflectance spectroscopy, which confirms the reduction of band gap upto 2.5 mol% doping of Zn. BET surface area analysis shows the decrease in surface area with increase in Zn concentration. All the synthesized samples show significant catalytic activity for reduction of 4-nitrophenol in the presence of NaBH4 as reducing agent. Catalytic studies indicate that 2.5 mol% Zn doped nanoparticles show 3 times enhanced catalytic activity as compared to that of pure SnO2 nanoparticles.