Comparative study of different nano-TiO_2 loaded cotton fabrics applied in dye degradation

Two low temperature synthesized nano-TiO2 hydrosols and two commercial nano-TiO2powders( 5 nm and 30 nm) were used to prepare four different nano-TiO2 loaded cotton fabrics using pad-dry process,respectively. After characterizing,their photocatalytic performance were evaluated and compared in the degradation of Acid Red 88. The results indicated that four nano-TiO2 were characterized to be anatase type. However,the nano-TiO2 particles in the hydrosols were imperfect crystals. The photocatalytic performance of two nano-TiO2 hydrosols and the nano-TiO2powder( with 5 nm size) loaded cotton fabrics were higher than that of nano-TiO2powder( with 30 nm size) loaded cotton fabric in acidic and neutral media. But,nano-TiO2powder( with 30 nm size) loaded cotton fabric had better catalytic activity than two nano-TiO2 hydrosols and the nano-TiO2powder( with 5 nm size) loaded cotton fabrics in alkaline medium or in the presence of Na Cl or SDBS.