Core-Shell Heterostructured and Visible-Light-Driven Titanoniobate/TiO₂ Composite for Boosting Photodegradation...

Area of Science:

• Materials Science
• Nanotechnology
• Environmental Chemistry

Background:

• Developing efficient photocatalysts for environmental remediation under visible light is crucial.
• Core-shell heterostructures offer unique advantages for charge separation and transport.
• Sulfur doping in titanium dioxide can create intra-band-gap states, enhancing visible light absorption.

Purpose of the Study:

• To synthesize and characterize a novel 1D S-doped K3Ti5NbO14@TiO2 (STNT) core-shell heterostructure.
• To investigate the enhanced photocatalytic degradation activity of STNT composites under visible light.
• To elucidate the role of sulfur doping and heterojunction formation in photocatalytic performance.

Main Methods:

• A simple reassembly-calcination method was employed using thiourea as the sulfur source.
• The morphology and structure of the synthesized materials were characterized.
• Photocatalytic degradation of methylene blue (MB) under visible light was evaluated.

Main Results:

• The synthesized STNT composite exhibited a 1D core-shell heterostructure with anisotropically shaped rods.
• Sulfur substitution into the TiO2 lattice created Ti-O-S bonds, enabling visible light response.
• STNT composites demonstrated significantly enhanced visible-light-driven photocatalytic degradation of MB compared to pure K3Ti5NbO14.
• The enhanced activity is attributed to synergistic effects of S doping and the nano-heterojunction structure, which promotes charge carrier separation and reduces recombination.

Conclusions:

• The S-doped K3Ti5NbO14@TiO2 core-shell heterostructure is a highly efficient visible-light photocatalyst.
• Sulfur doping and heterojunction formation are effective strategies for enhancing photocatalytic activity.
• This work provides insights into designing advanced photocatalysts for sustainable environmental remediation.