Synthesis and characterization of TiO2/ZnCr2O4 core-shell structure and its photocatalytic and antibacterial activity
| Autor: | Akbar Eshaghi, Mozhgan Salehi, Hamid Tajizadegan |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Materials science
Nanocomposite Absorption spectroscopy Precipitation (chemistry) Band gap Mechanical Engineering Spinel Metals and Alloys Heterojunction 02 engineering and technology engineering.material 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Chemical engineering Mechanics of Materials Materials Chemistry engineering Photocatalysis 0210 nano-technology Absorption (electromagnetic radiation) |
| Zdroj: | Journal of Alloys and Compounds. 778:148-155 |
| ISSN: | 0925-8388 |
| DOI: | 10.1016/j.jallcom.2018.11.025 |
| Popis: | A shell of ZnCr2O4 spinel was facilely covered on the surface of TiO2 nanoparticles to synthesize TiO2/ZnCr2O4 core-shell structure using TiO2 seed particles and heterogeneous precipitation. The as-prepared nanocomposite was characterized in terms of crystal structure, morphology and surface area, light absorption and band gap. After coupling TiO2 with ZnCr2O4, a heterojunction formed between the two semiconductor materials. UV–vis absorption spectra showed a red shift of the absorption edges and lower band gap of 3.0 eV for the composite system compared to the single phase TiO2 (3.4 eV) due to the formation of new energy level at the core-shell interface. Photocatalytic activity of the nanocomposites was evaluated by degradation of methylene blue under UV-light irradiation, revealing that the core-shell nanocomposite exhibits superior photocatalytic activity (99% yield) compared to the single phase TiO2 (40% yield) even after 4 consecutive reaction runs. In fact, this enhancement was attributed to the efficient separation and migration of the photogenerated electron–hole pairs at the core-shell interface due to the formation of energy bands heterojunction at the interface. Also, it was found that the synthesized core-shell structure is a highly effective antibacterial material against E. coli bacteria. |
| Databáze: | OpenAIRE |
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