Hydrogen　sulfide　(H2S)　is　considered　to　be　a　broad-spectrum　toxicant,　and　it　is　crucial　to　address　this　problem　due　to　its　serious　health　and　climate　change　impacts.　Photocatalysis　can　be　effectively　applied　for　the　reduction　of　H2S　molecules　to　S　and　other　products.　We　synthesized　sandwich-structured　composite　materials　with　internally　immobilized　SiO2　nanospheres　and　externally　wrapped　COF　layers　co-modified　with　iron　oxide　nanoparticles.　Furthermore,　originally　looked　at　the　efficiency　of　photocatalysis　in　reducing　hydrogen　sulfide　to　sulfur.　In　this　paper,　a　sandwich　structure　of　core–shell　composite　photocatalysts　based　on　SiO2　was　prepared　by　a　multi-step　method　including　Stöber　and　double　ligand-regulated　solvent　heat,　and　these　sandwich　core–shell　structures　exhibited　high　hydrogen　sulfide　reduction　and　stability　in　applications.　In　addition,　characterization,　degradation　studies,　active　substance　trapping　studies,　and　energy　band　structure　analysis　showed　that　S-type　heterojunctions　could　effectively　increase　photo-generated　carrier　separation.　This　research　advanced　knowledge　of　photocatalytic　hydrogen　sulfide　reduction　and　offered　a　novel　approach　for　catalysts　in　COF　sandwich　core–shell　structures.　©　2023