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It is highly desirable to exploit semiconductor materials with high photocatalytic degradation activity,es-pecially bismuth oxyhalide semiconductor photocatalysts with special layered structure and suitable bandgap width.The low utilization rate of visible light and high recombination rate of photogenerated electron-hole of BiOI photo-catalyst severely restrict its development.Herein,a heterojunction photocatalyst of α-Bi2O3-BiOI hollow nanotube was prepared by electrospinning method,solvothermal method and ion-exchange method.The α-Bi2O3-BiOI(BB-4,the stirring time of Bi2O3 in KI solution was 4 h)exhibited the best photocatalytic performance towards degrading the tetracycline hydrochloride(TC)solution,which could remove 85%of TC(10 mg/L)in 2 h under visible light irradia-tion.The estimated krc of α-Bi2O3-BiOI(BB-4)was ca.3.9 and 1.8 times as much as that of α-Bi2O3 and pure BiOI,respectively.It indicated that the formation of α-Bi2O3-BiOI heterojunction can significantly improve the separation efficiency of photogenerated electron-hole pairs,therefore the photocatalytic ability was enhanced.Furthermore,a corresponding photocatalytic mechanism was proposed that·O2-radical and holes are the main active components in the photodegradation through trapping experiment.