A method for preparing for a photocatalyst. The method comprises steps of
providing a mixture of indium oxide and vanadium oxide and then calcining
the mixture to obtain a indium vanadium quadrioxide. Further, a nickel
nitrate solution is added to the indium vanadium quadrioxide to form a
catalyst with a nickel oxide supported amount of about 0.1-2.0 wt. % and
a post treatment is performed on the catalyst. In the post treatment, a
reduction process is performed and then an oxidation process is
performed.