A review on the synthesis of the TiO2-based photocatalyst for the environmental purification

TiO2 as a photocatalyst has been widely investigated and applied in many fields such as fuel cells, sterilization, and environmental decontamination. Some efforts, such as operation parameters, synthesis techniques, and improvements by doping have been made to improve its performance. To have a photocatalyst with high photocatalytic activity for environmental purification, the most important step is to know about the synthesis methods and the parameters and conditions that lead to preparing a highly photocatalytic active photocatalyst. This article paves the way in selecting the best synthesizing technique. In this article, the most common synthesis techniques of TiO2-based photocatalysts, including sol-gel, hydrothermal, solvothermal, chemical vapor deposition, and physical vapor deposition have been reviewed. The most important results that have been achieved in the field of synthesis were collected.