SnO2nanoparticles endowed Pt-TiO2 bowl nanoarraysenhanced redox ability towards efficient tetracycline hydrochlorideremoval andH2 generation

A novel approach is developed to construct Z -scheme heterojunctions via growing SnO 2 nanoparticles on Pt decorated hollow TiO 2 bowl nanoarrays (TBN) towards efficient photogenerated charge carrier separation and transfer to enhance the redox ability of resulting catalysts. Namely, sample TBN was fabricated using hollow carbon spheres as templates, in which highly crystalline TiO 2 nanoparticles (less than 10 nm) were assembled into nanoarray to construct hollow bowl spheres. Homogeneously distributed small Pt nanoparticles in TBN govern the growth of SnO 2 nanoparticles via a solvent thermal route and finally to create Z -scheme TiO 2 /Pt/SnO 2 heterojunctions. Pt loading between SnO 2 and TBN components improved photogenerated charge carrier separation and transfer efficiencies and enhanced photocatalytic performance. TiO 2 /Pt/SnO 2 heterostructure samples exhibited improved performance for tetracycline hydrochloride removal with a pseudo-first-order kinetic reaction constant of k = 0.080 min −1 which were 3.8 and 6.7 times of those of TBN (k = 0.012 min −1 ) and TBN/SnO 2 composites (sample TS, k = 0.021 min −1 ), respectively. Moreover, the photocatalytic hydrogen generation rate of TiO 2 /Pt/SnO 2 heterostructures without using co-catalyst was 3511.9 μmol·g −1 ·h −1 which was 2.3 times of that of sample TS using Pt as co-catalyst. These results provided new sights for synthesis of photocatalysts especially for the removal of antibiotic pollutants.