Construction of 2D layered TiO₂@MoS₂heterostructure for efficient adsorption and photodegradation of organic dyes

Area of Science:

• Materials Science
• Environmental Science
• Nanotechnology

Background:

• Developing efficient photocatalysts and adsorbents is crucial for addressing water pollution.
• Titanium dioxide (TiO2) and molybdenum disulfide (MoS2) are promising materials for environmental applications.
• Heterostructuring TiO2 with MoS2 can enhance their combined properties for pollutant degradation and adsorption.

Purpose of the Study:

• To synthesize and characterize TiO2@MoS2 heterostructures with different MoS2 phases.
• To evaluate the photocatalytic degradation of methyl orange (MO) and adsorption of Rhodamine B (RhB) and methylene blue (MB) dyes using the synthesized nanocomposites.
• To investigate the structure-property relationships influencing the performance of TiO2@MoS2 heterostructures.

Main Methods:

• Hydrothermal synthesis of TiO2@MoS2 heterostructures.
• Comprehensive material characterization using XRD, SEM, TEM, BET, XPS, Zeta potential, and UV-vis spectroscopy.
• Photocatalytic degradation and adsorption experiments under visible light.

Main Results:

• TiO2@1T/2H-MoS2 heterostructures exhibited a narrow bandgap, promoting efficient electron transfer and carrier separation.
• Complete degradation of 20 ppm methyl orange within 60 minutes with high stability over four cycles.
• Rapid removal of 20 ppm Rhodamine B and methylene blue within 1 and 2 minutes, respectively, with high adsorption capacities (1200 mg/g for RhB, 970 mg/g for MB).

Conclusions:

• The TiO2@1T/2H-MoS2 heterostructure demonstrates superior photocatalytic and adsorption performance for water remediation.
• The enhanced efficiency is attributed to the unique heterostructure, aligned energy bands, high surface area, and active sites.
• This study presents a viable strategy for designing advanced TiO2-based nanocomposites for effective water purification.