Solar light driven water oxidation photocatalyst Bi20TiO32 has been successfully synthesized through sol gel process. Photocatalytic activity of Bi20TiO32 for oxygen evolution using silver nitrate as sacrificial agent under UV light and visible light irradiation have also been studied and enhanced by the addition of co-catalyst iridium oxide and platinum to the photocatalyst. Furthermore, overall water splitting reaction using Bi20TiO32 in combination with CuFeO2 has also been conducted by conventional and modified Z-scheme process in both single and twin reactor. Photo-reduced graphene oxide and co-catalyst iridium oxide and ruthenium have been used to enhance photocatalytic activity water splitting.