CTAB-aided surface-modified tin oxide nanoparticles as an enhanced photocatalyst for water treatment

The surfactant-assisted SnO2 nanoparticles were successfully prepared by a simple hydrothermal system with different reaction time intervals of 12 and 24 h. In this work, the cetyl trimethyl ammonium bromide (CTAB) surfactant used as the ligand as well as a morphology-controlling agent for SnO2 nanoparticles. The as-prepared and CTAB-assisted samples were systematically analysed by XRD, FTIR, UV, PL, SEM, TGA and DSC analyses. The XRD results clearly show that the formation of good crystalline SnO2 nanoparticles with tetragonal structure. The SEM images confirm the morphological influence of CTAB in SnO2 nanoparticles. The improved morphology gives a more active surface for the photocatalytic reaction and as a result, enhanced catalytic efficiency was observed. Similarly, the enhanced dye degradation ability was attributed to the effective production and use of photogenerated charge carriers on the surface of the tetragonal SnO2 nanoplates towards the free radical formation. The role of active species in the catalytic process was investigated through a radical trapping experiment. The prepared catalyst shows superior photocatalytic activity, even after three consecutive cycles.