TiO2/ZnO: Type-II Heterostructures for electrochemical crystal violet dye degradation studies

Abstract

Semiconductor nanomaterials with proper band edge alignments forming “heterostructure” assemblies have significant importance in water splitting, dye degradation, and other electrochemical studies. The formed heterojunction between material phases facilitates fast charge carrier transport and, thereby, improves electrochemical performance in associated processes. Herein, we report a type-II heterostructure combining TiO2 and ZnO nanomaterials for electrochemical crystal violet dye degradation studies. The rationale in choosing the above materials (TiO2, ZnO) in the present study includes stability, lack of toxicity, and high oxidation power, but they also facilitate fast charge carrier movements due to proper band edge alignments, forming a type-II heterostructure assembly. Cyclic voltammetry, combined with ultraviolet-visible analysis, was used to identify the cathodic and anodic peak currents and trace the exact mechanism of dye degradation. The electro-catalytic performance of TiO2/ZnO heterostructured materials fabricated on titania (Ti) substrate show higher performance, in comparison to all individual material interfaces, due to synergistic interaction and synchronized charge transport.

The Impact of Tilt Angle and Flowrate on Performance of Nanofluid Based Photovoltaic/ Thermal (PV/T) Solar Collectors

“…On the other hand, this amount is between 500-1000 in December and January for all working fluid and flowrates. Furthermore, the tangible impact of the nanofluid's concentration on output thermal energy also can be found in figure (8). For instance, in July, this amount surges from 1397 to 1851 MJ for water and Ag3.…”

“…The most determinative parameter in this study is output thermal energy decreasing the consumption of fossil fuels in conventional hot water supply system. The total amount of thermal energy producing in each months by PV/T solar collector is demonstrated in figure (8). Based on the figure (8), there are some critical design parameter affecting the total output thermal energy in different months.…”

“…The total amount of thermal energy producing in each months by PV/T solar collector is demonstrated in figure (8). Based on the figure (8), there are some critical design parameter affecting the total output thermal energy in different months. As it is understood from previous parts, the more solar radiation, the more thermal energy can be gained by PV/T solar collector.…”

“…Therefore, the enhancement of thermal conductivity engendering to more heat is dissipated from the photovoltaic panel and more energy is obtained by working fluid. Also, in recent years, with the advancement of nanotechnology, numerous researchers have studied the use of nanofluids to improve heat transfer in engineering applications [5][6][7][8][9][10]. Thus, by application of the properties of nanofluids in PV/T solar collectors, the performance of this solar system can be improved.…”

A Comprehensive Review on Modification of Titanium Dioxide‐Based Catalysts in Advanced Oxidation Processes for Water Treatment

“…The heterostructure of TiO 2 /ZnO composite used as electrode shows high performance with 85 % decolorization after 6.5 h. This increase in electrocatalytic activity is linked to the synergistic interaction between these two metal oxides with a synchronized charge transport (Figure 23) leading to a rapid elimination of pollutant with low energy consumption. [184] In addition, Mirmasoomi et al synthetized TiO 2 /Fe 2 O 3 nanocomposite by ultrasonic-assisted impregnation method. The prepared material was used as photocatalyst for degradation of diazinon.…”