Synthesis and Photocatalytic Activity of TiO2/CdS Nanocomposites with Co-Exposed Anatase Highly Reactive Facets

Yi-En Du; Xianjun Niu; Xinru He; Kai Hou; Huiling Liu; Caifeng Zhang

doi:10.3390/molecules26196031

Synthesis and Photocatalytic Activity of TiO₂/CdS Nanocomposites with Co-Exposed Anatase Highly Reactive Facets

Molecules. 2021 Oct 4;26(19):6031. doi: 10.3390/molecules26196031.

Authors

Yi-En Du¹, Xianjun Niu¹, Xinru He¹, Kai Hou¹, Huiling Liu², Caifeng Zhang³

Affiliations

¹ Department of Chemistry and Chemical Engineering, Jinzhong University, Jinzhong 030619, China.
² Department of Mechanics, Jinzhong University, Jinzhong 030619, China.
³ Department of Chemistry, Taiyuan Normal University, Jinzhong 030619, China.

Abstract

In this work, TiO₂/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 [Ti₄O₉]^2- 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 TiO₂/CdS nanocomposites were characterized. The photocatalytic activity and cycling performance of the TiO₂/CdS nanocomposites were also investigated. The results showed that as-prepared FMA-TiO₂/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-TiO₂/CdS was 0.0167 min^-1, which was 55.7, 4.0, 3.7, 3.5, 3.3, and 1.9 times of No catalyst, CdS, HF-TiO₂/CdS, NH₄F-TiO₂/CdS, CM-TiO₂, Urea-TiO₂/CdS, respectively. The highest photocatalytic activity of FMA-TiO₂/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.

Keywords: TiO2/CdS nanocomposites; highly reactive facets; photocatalytic activity; synergistic effects.