Photocatalytic hydrogen production over various sodium tantalates

• A series of NaTaO3, Na2Ta2O6 and composite sodium tantalates have been prepared via hydrothermal route. • The crystal structure, morphology and textural parameters of the materials could be controlled by changing the pH and reaction time. • The catalytic activities of the prepared samples were investigated for photolysis of water. • The highest photocatalytic activity is achieved with Na2Ta2O6 nanoparticles with the highest surface area. • An enhanced H2 production was obtained for composite materials that was attributed to junctions of sodium tantalate phases