Hydrothermal synthesis of TiO2 hollow spheres adorned with SnO2 quantum dots and their efficiency in the production of methanol via photocatalysis.

TiO2 hollow spheres and TiO2 hollow spheres adorned with SnO2 quantum dots were synthesized successfully under mild temperature and autogenous pressure using the hydrothermal route. X-ray diffraction, field emission scanning electron microscopy, scanning electron microscopy, transmission electron microscope, photoluminescence spectroscopy, and UV-vis spectroscopy were used to characterize the physical and chemical nature of the synthesized sample. The characterized samples were used in the photocatalytic applications to reduce the concentration of carbon dioxide in the presence of water under the influence of visible light. Our observation confirmed that with increasing SnO2 content there is a tremendous change in the photocatalytic performance of the samples, due to free mobility of the electrons and holes and decline in charge recombination centers formed with the formation of nano-heterojunction between SnO2 and TiO2. The greater photocatalytic production of methanol was achieved using 2ST sample, i.e., 1.61 μmol/g/h which tends to decrease with an increase in SnO2 content.