Hydrogen production from Hydrogen Sulfide Wastestream using Ru/Cd_0.6Zn_0.4S Photocatalyst

Thangam N, Suganya Devi B, Lalitha Muthu AC

The depletion of non-renewable energy source and increasing levels of environmental pollution are both becoming serious global concerns. The conversion of solar energy into hydrogen via H₂S splitting process assisted by semiconductor photocatalysts is one of the most attractive and focused way of achieving clean and renewable energy systems. A novel Ru ²⁺ doped Cd_0.6Zn_0.4S nanophotocatalyst was synthesized by co-precipitation method. The physical characterization of the nanophotocatalyst had been carried out by XRD, SEM, UV-DRS and EDS. The XRD patterns showed that a new structural peak was found instead of original peaks with mixture of Ru doped Cd_0.6Z_0.4S having a particle size of 4.9 nm. The band gap energy of 2.61 eV and threshold wavelength of 475 nm were found using UV-DRS.The photocatalytic generation of H₂ from simulated sulfide wastewater under visible light irradiation were conducted with two different reactors viz., trapezoidal and cylindrical tapered bottom reactors. The comparison of performance also reveals that the trapezoidal reactor produce higher rate of H₂ production (4063 µmol/h) than the cylindrical tapered bottom reactor (3169 µmol/h). The quantum efficiency of 10.1% at 560 nm was found in trapezoidal reactor. This composite exhibited much higher photocatalytic activity for the generation of hydrogen (H₂).