Template-free hydrothermal synthesis of SrSO4:Sm3+ microrods and its electron trapping luminescence properties

► SrSO4 samples obtained at different pH values have different morphologies. ► pH value is the key factor in the formation of rod-like morphology of SrSO4. ► The width of SrSO4 nanorods and microrods are 350 nm and 2 μm, respectively. ► The synthesis process does not use of any catalysts, toxic reagent or surfactants.