A new strategy is reported for the synthesis of supported metal sulfides with high dispersion by sulfidation in dielectric barrier discharge (DBD) plasma under ambient conditions. According to the characterization data obtained by XRD, BET, UV-vis, TEM, XPS, ICP, and elemental analysis, the DBD plasma method not only reduces the preparation time but also achieves an increased dispersion, small particle size and uniform distribution compared to the traditional thermal method. These results prove that the plasma preparation method is a facile and flexible approach for the synthesis of metal sulfides. The plasma-prepared CdS/Al2O3 and ZnS/Al2O3 catalysts exhibited high performances for hydrogen production from H2S with reduced energy costs. The enhancement might be attributable to the smaller particle size, higher surface area and dispersion, which enhances the semiconductor catalytic efficiency.

The decomposition of hydrogen sulfide (H2S) has attracted increasing attention because it produces hydrogen from a hazardous waste gas. However, the thermal equilibrium limitation in the decomposition gives rise to low H2S conversion and high energy costs for hydrogen production. In the present work, we demonstrate that alumina-supported CdS and ZnS significantly enhanced the conversion in the non-thermal plasma-induced decomposition of H2S, achieving full conversion at reasonably low energy consumption. It appears that the enhancement might be attributed to the conversion of H2S by its reaction with h+ and e− on the surface of the CdS and ZnS semiconductors, which are generated by the strong electric field and plasma-induced photons.

•Full conversion was achieved in H2S decomposition by plasma plus semiconductor.•The enhancement is attributable to the surface hole–electron pairs.•The performance of the semiconductor catalysts was stable in the 100 h runs.•Zn0.4Cd0.6S/Al2O3 exhibited higher performance than ZnS/Al2O3 and CdS/Al2O3.Direct H2S decomposition induced by plasma with an aid of alumina-supported metal sulfide semiconductors (ZnS/Al2O3 and CdS/Al2O3) for the production of hydrogen was investigated in a dielectric barrier discharge (DBD) reactor. Effects of specific input energy (SIE), feed flow rate, metal sulfide loading, and added hydrogen on the performance of H2S decomposition were studied. With the aids of ZnS/Al2O3 and CdS/Al2O3, full conversion was obtained at reasonably low energy costs. The 100-h test runs indicated that both ZnS/Al2O3 and CdS/Al2O3 were stable in the course of H2S decomposition. A supported metal sulfide solid solution (Zn0.4Cd0.6S/Al2O3) exhibited higher performance than ZnS/Al2O3 and CdS/Al2O3, achieving full conversion at a reduced energy cost. The mechanism of the plasma-induced H2S decomposition with an aid of a semiconductor catalyst was tentatively proposed.