Preparation of amorphous and nanocrystalline sodium tantalum oxide photocatalysts with porous matrix structure for overall water splitting

► Synthesis of NaTaO3 and Na2Ta2O6 nanoparticle photocatalyst with porous matrix structure using single precursor. ► Amorphous porous photocatalyst synthesized using low temperature. ► Nano-photocatalysts display higher activity than bulk materials without co-catalyst. ► Amorphous photocatalyst displayed higher hydrogen production rates than nanocrystalline photocatalyst.