The　conversion　of　solar　energy　into　H2　energy　by　photocatalytic　biomass　decomposition　has　become　a　research　hotspot　in　recent　years.　In　this　work,　Co3S4/Zn0.5Cd0.5S　(CS/ZCS)　composites　with　a　series　of　mass　ratio　were　prepared　by　loading　ZCS　nanoparticles　on　the　surface　of　Co3S4　polyhedron,　and　characterized　by　many　advanced　tests.　Moreover,　their　photocatalytic　activity　of　H2　production　were　explored　by　biomass　decomposition,　like　lactic　acid　(LA)　and　benzyl　alcohol　(PhCH2OH).　When　the　amount　of　Co3S4　cocatalyst　is　4　wt%,　the　H2　production　of　the　composite　photocatalyst　reaches　the　highest,　which　is　17.86　mmol·g−1·h−1　for　LA　and　20.07　mmol·g−1·h−1　for　PhCH2OH,　much　higher　than　ZCS　nanoparticles.　Co3S4　cocatalyst　as　the　electrons　(e−)　trapper　of　ZCS,　enhances　the　absorption　of　visible　light　and　improves　the　migration　efficiency　of　the　photogenerated　charge　carriers　(PCCs),　thus　greatly　increasing　the　photocatalytic　H2　production.　This　work　may　play　an　important　role　in　improving　H2　production　from　biomass　decomposition　for　metal　sulfide.　©　2023　Elsevier　B.V.