Comprehensive Review on Fabrication Techniques of Nitrogen and Iron Co-doped TiO2

TiO2 photocatalyst co-doped with iron and nitrogen have attracted great attention for environmental applications. This paper reviews preparation methods of this photocatalyst using sol-gel, hydrothermal, and impregnation–calcination techniques. Moreover, the photocatalytic activities for the degradation of various pollutants are evaluated under visible light. This paper also discusses the effect of Fe3+-doping concentration on the photocatalytic activities. Finally, it is concluded that the photocatalyst fabricated by hydrothermal method with small Fe3+ content (0.5% mole fraction) can remove pollutant (Rhodamine B) completely under visible light.