In　the　present　study,　the　authors　found　that　the　growth　of　sulfide　catalyst　crystals　involved　the　dissolution-recrystallization　process,　resulting　in　the　formation　of　stacking　fault　structured　homojunctions　through　the　theoretical　calculation　and　analysis　of　the　chemical　equilibrium　in　the　synthetic　process　for　sulfide　catalysts.　It　was　also　revealed　that,　compared　with　the　alkali　solution,　using　an　alkaline　ammonia　solution　as　the　hydrothermal　solvent　could　promote　more　NiS　cocatalysts　to　be　distributed　on　the　surface　of　the　sulfide　catalysts,　leading　to　the　formation　of　more　p-n　junctions.　Both　the　p-n　junctions　and　the　stacking　fault　structures　effectively　promoted　the　separation　of　photogenerated　charges,　leading　to　a　quantum　efficiency　at　420　nm　of　up　to　74.6%,　which　is　the　highest　efficiency　reported　to　date　among　visible-light-driven　photocatalysts　without　noble　metal　cocatalysts.　Research　of　chemical　equilibrium　in　the　synthetic　process　for　the　CdZnS　solid　solution,　it　was　revealed　that　certain　amounts　of　CdS　and　ZnS　may　exist,　thus　forming　a　three-phase　detached　catalyst　(CdS　and　ZnS　single-phases　and　CdZnS　solid　solution　phase).　In　this　way,　the　structure　could　improve　the　hydrogen　production　performance　of　the　CdZnS　solid　solution.　The　results　were　also　confirmed　by　characterization　of　the　catalysts.　©　2020　Hydrogen　Energy　Publications　LLC