Improved Photocatalytic Performance via Air-Plasma Modification of Titanium Dioxide: Insights from Experimental and Simulation Investigation

TL;DR

This study demonstrates that ambient air-plasma treatment of titanium dioxide reduces crystallite size and creates oxygen vacancies, leading to enhanced photocatalytic degradation of pollutants, supported by experimental and simulation insights.

Contribution

It introduces a cost-effective plasma modification method that improves titanium dioxide's photocatalytic performance and stability, supported by experimental results and density functional theory calculations.

Findings

Plasma treatment reduces crystallite size and creates oxygen vacancies.

Enhanced photocatalytic degradation of methylene blue observed.

4-hour plasma-treated catalyst shows good stability and reusability.

Abstract

Commercial titanium dioxide is successfully plasma-treated under ambient conditions for different time periods, leading to reduced crystallite size and the creation of oxygen vacancies. Density functional theory-based calculations reveal the emergence of additional localized states close to the conduction band, primarily associated with under-coordinated titanium atoms in non-stoichiometric titanium-oxide systems. The plasma-treated samples exhibit improved photocatalytic performance in the degradation of methylene blue compared to untreated samples. Moreover, the 4-hour plasma-treated photocatalyst demonstrates commendable stability and reusability. This work highlights the potential of cost-effective plasma treatment as a simple modification technique to significantly enhance the photocatalytic capabilities of titanium dioxide.