We　report　a　photochemical　bismuth　vanadate　(BiVO4)　sensing　material,　which　possesses　a　large　proportion　of　(110)　and　(011)　facets　combined　with　the　additional　(111)　facets,　for　the　selective　detection　of　ultra-low　concentration　hydrogen　sulfide　(H2S)　driven　by　visible　light.　Specifically,　the　obtained　octadecahedron　BiVO4　(Octa-BiVO4)　performs　a　high　response　value　(67)　and　short　response　time　(47.4　s)　to　100　ppm　H2S　with　good　stability　for　nearly　100　days,　as　well　as　undisturbedness　by　moist　air.　With　the　combination　of　experimental　and　theoretical　calculation　results,　the　adsorption　and　carrier　transfer　behaviors　of　H2S　molecules　on　the　Octa-BiVO4　crystal　surface　are　investigated.　By　adjusting　the　ratio　of　different　crystal　facets　and　controlling　the　facets　with　characteristic　adsorption,　we　achieve　improved　anisotropic　photoinduced　carrier　separation　and　high　selectivity　for　a　specific　gas.　Furthermore,　this　facial　facet　engineering　can　be　extended　to　the　synthesis　of　other　sensing　materials,　offering　huge　opportunities　for　fundamental　research　and　technological　applications.