Mustard　gas　is　a　kind　of　erosive　poison　with　great　harm　and　used　as　a　chemical　weapon　since　World　War.　It　has　suggested　that　the　photocatalytic　technology　is　an　effective　method　to　eliminate　it.　Because　the　small　difference　in　molecular　structure　between　2-CEES　and　Mustard　gas,　and　the　less　toxic　of　2-CEES,　2-CEES　is　often　used　as　a　simulator　to　evaluate　the　photocatalytic　activity　of　catalysts.　In　this　work,　symbiotic　mixture　of　Bi2WO6　and　Bi6O6(OH)3(NO3)3·1.5H2O　nanosheets　doped　with　Mo　(Mo-B-B)　have　been　synthesized　by　a　facile　hydrothermal　treatment.　The　samples　were　characterized　by　XRD,　DRS,　XPS,　SEM,　TEM,　Raman,　and　PL.　The　photocatalytic　activity　of　the　samples　was　evaluated　by　measuring　the　degradation　of　2-CEES　under　visible　light　irradiation.　The　results　showed　that　the　doped　Mo　reduce　the　Eg　of　bare　symbiotic　mixture　and　improve　the　separation　efficiency　of　photo-generated　carriers　that　is　beneficial　to　photocatalytic　activity.　The　optimum　amount　of　doped　Mo　is　5%　that　exhibits　the　best　activity　for　degradation　for　2-CEES.　©　2022,　The　Author(s),　under　exclusive　licence　to　Springer　Nature　B.V.