Enhanced photocatalytic reduction of aqueous Re(VII) in ambient air by amorphous TiO2/g-C3N4 photocatalysts: Implications for Tc(VII) elimination

•A simple amorphous TiO2/g-C3N4 composite photocatalyst was fabricated.•This photocatalyst has the excellent specific surface area and narrow band gap.•XPS and XAFS results suggest that Re(VII) should be mainly reduced to Re(IV).•It exhibits the extremely slow re-dissolution of Re(IV) when compared with P25.•This photocatalyst containing amorphous TiO2 can be used for Tc elimination.