Transition metal oxide based TiO2 nanoparticles for visible light induced CO2 photoreduction

Abstract

The development of nanostructured visible light photocatalytic systems capable of harnessing the energy from the sun is imperative for producing carbon based fuels and chemicals. V-, Cr- and Co-TiO2 photocatalysts immobilized onto quartz plates were successfully prepared by sol–gel method, investigated as a function of metal concentration and tested for visible light induced CO2 reduction for the first time. Results established that introduction of these metal ions into the host framework not only modified the crystallinity of TiO2, but influenced its light absorption properties as well. Enhanced bathochromic shift from the UV region to longer wavelengths in the visible light region was observed with increasing metal concentrations for all samples especially Cr. The photoconversion rates were remarkably enhanced by the metal doped TiO2 supports when compared to pure TiO2, with the Co-TiO2 samples having the highest photoconversion rates.