Design and fabrication of ellipsoidal α-Fe 2 O 3 @SnO 2 core-shell microspheres with heterostructures for improving photocatalytic performance

alpha-Fe2O3@SnO2 2 O 3 @SnO 2 core-shell microspheres with heterostructures were successfully designed and fabricated using Na2SnO3 & sdot;4H2O 2 SnO 3 & sdot;4H 2 O as the tin source. The influence of Sn/Fe molar ratio and calcination temperature on the morphology and structures of alpha-Fe2O3@SnO2 2 O 3 @SnO 2 microspheres were systematically investigated. For the Sn/Fe molar ratio between 0.5 and 1.0, the optical absorption capacity of alpha-Fe2O3@SnO2 2 O 3 @SnO 2 microspheres is higher than that of pure SnO2 2 because of the heterostructures. With increasing the calcination temperature, the degree of crystallization and specific surface area of alpha-Fe2O3@SnO2 2 O 3 @SnO 2 microspheres also are progressively improved. The photocatalytic performance for Rhodamine B (RhB) degradation was subsequently assessed under sunlight-like irradiation. After calcination at 600 degrees C, the Fe/Sn-0.75 sample demonstrates the significant acceleration of photocatalytic degradation rates. The photocatalytic degradation rate under light irradiation after 8 h reaches 93.30 % and maintains at 89.98 % even after five cycles.