Synthesis and Photocatalytic Activity of TiO/CdS Nanocomposites with Co-Exposed Anatase Highly Reactive Facets.

In this work, TiO/CdS nanocomposites with co-exposed {101}/[111]-facets (NH4F-TiO2/CdS), {101}/{010} facets (FMA-TiO2/CdS), and {101}/{010}/[111]-facets (HF-TiO2/CdS and Urea-TiO2/CdS) were successfully synthesized through a one-pot solvothermal method by using [TiO] colloidal solution containing CdS crystals as the precursor. The crystal structure, morphology, specific surface area, pore size distribution, separation, and recombination of photogenerated electrons/holes of the TiO/CdS nanocomposites were characterized. The photocatalytic activity and cycling performance of the TiO/CdS nanocomposites were also investigated. The results showed that as-prepared FMA-TiO/CdS with co-exposed {101}/{010} facets exhibited the highest photocatalytic activity in the process of photocatalytic degradation of methyl orange (MO), and its degradation efficiency was 88.4%. The rate constants of FMA-TiO/CdS was 0.0167 min, which was 55.7, 4.0, 3.7, 3.5, 3.3, and 1.9 times of No catalyst, CdS, HF-TiO/CdS, NHF-TiO/CdS, CM-TiO, Urea-TiO/CdS, respectively. The highest photocatalytic activity of FMA-TiO/CdS could be attributed to the synergistic effects of the largest surface energy, co-exposed {101}/{010} facets, the lowest photoluminescence intensity, lower charge-transfer resistance, and a higher charge-transfer efficiency.