Na2S/Na2SO3溶液促进NiS2/Mn0.5Cd0.5S肖特基/S型孪晶同质结光催化转化H2SOA

The concurrent production of hydrogen(H2)and high-value products from waste and toxic hydrogen sulfide(H2S)has long been a goal in the field of photocatalytic decomposition of H2S.In this study,the twinned Mn0.5Cd0.5S(T-MCS)was selected for its combination of solid solution and twin structure advantages,significantly promoting the bulk phase separation of CdS-based photocatalysts.Furthermore,the highly conductive nickel disulfide(NiS2)was loaded onto T-MCS to create a NiS2/T-MCS composite photocatalyst that features both a bulk phase S-scheme homojunction and an interface Schottky junction.NiS2 not only introduces a large number of active sites,but also improves the separation of surface charges obviously.Utilizing a 0.1 mol L-1(M)sodium sulfide(Na2S)and 0.6 M anhydrous sodium sulfite(Na2SO3)solution saturated with H2S as the reaction solution,the 8 wt%NiS2/T-MCS composite achieves a remarkable hydrogen production rate of up to 59.95 mmol h-1 g-1.Fourier Transform Infrared(FTIR)spectroscopy and Ultraviolet-Visible(UV-Vis)spectroscopy confirm that the sulfur compounds in the reaction solution are nearly completely converted into high-value sodium thiosulfate(Na2S2O3).The S2O32-was also quantitatively determined by titration.This work presents a novel solid solution twin crystal-based homojunction and Schottky junction for both the photocatalytic treatment of H2S and the production of Na2S2O3.