Method of making photocatalysts by loading titanuim dioxide film on flexible substrates

A method of making a photocatalyst by loading titanium dioxide film on a flexible substrate, comprising the steps of:

• (1) preparing an active layer sol-gel by:
• (a) making a precursor solution comprising n-butyl titanate, ethanol, diethanolamine, and water in the volume ratio of n-butyl titanate ethanol:diethanolamine:water=1:8-12:0.1-0.15:0.05-0.06;
• (b) adding a pore-forming agent selected from the group consisting of polyglycol, octadecylamine, and mixtures thereof to the precursor solution of step (1) a), wherein the mass ratio of the amount of the pore-forming agent to the amount of the ethanol in the precursor solution is pore-forming agent:ethanol=1%-30%:1;
• and
• (c) placing the resulting solution in a sealed gelatinization process for at least 3 days;
• and
• (2) preparing an active TiO2 photocatalyst layer by:
• (a) coating a flexible substrate with the active layer sol-gel prepared according to step (1) using a pulling and coating method;
• (b) drying the coated flexible substrate;
• and
• (c) placing the coated, dried flexible substrate in a hydrothermal kettle for thermal crystallization in a mixed solvent of ethanol and water at 60-200° C.