Solvothermal synthesis of CdS nanowires for photocatalytic hydrogen and electricity production

To investigate the formation of one-dimensional CdS nanowires, we synthesized them by a solvothermal method in ethylenediamine as a single solvent at different temperatures and times. The sample synthesized at 160 °C for 72 h had an average diameter of ca. 50 nm and a length of ca. 3-4 μm and hexagonal phase with high crystallinity. It was revealed that the formation of CdS nanowires followed three-step processes during the solvothermal synthesis; the seed formation process yielded nanosheets emanating from a mirosphere followed by the nanorod formation and growth of nanorods to nanowires. The CdS nanowires with higher crystallinity showed a higher rate of photocatalytic hydrogen production from water containing 0.1 M Na₂S and 0.0 2M Na₂SO₃ as sacrificial reagents under visible light irradiation (λ ≥ 420 nm). A high and stable photocurrent generation was also observed from the CdS nanowire film under visible light.