Bi2Sn2O7 nanoparticles are loaded onto CeO2 microspheres via hydrothermal method to produce Z-type heterojunction for photocatalytic degradation of contaminants in water.Results show that the degradation efficiency of tetracycline hydrochloride by the optimized Bi2Sn2O7/CeO2(BSC-5)reaches 88.4%after 60 minutes of exposure to light(reaction rate constant k=0.033 4 min-1),which is 8.25 times that over CeO2 and 4.71 times that over Bi2Sn2O7.Z-type heterojunction can form more exposed active centers,presenting better photoelectron-hole pair separation efficiency and excellent redox ability,and effectively generating superoxide radicals(·O2-)and hydroxyl radicals(·OH).In addition,Bi2Sn2O7/CeO2 shows good stability in photocatalytic degradation experiments,and delivers a degradation efficiency above 85%after 5 cycles.Meanwhile,the photocatalytic mechanism of Bi2Sn2O7/CeO2 photocatalyst is elucidated on the basis of experimental study.