ZnIn2S4 has emerged in water splitting and degradation ot dyes due to its good stability and light absorption properties.However,there are still few reports of CO2 photoreduction.Herein,we successfully synthesized Znln2S4 and obtained a series of ZnIn2S4-CdIn2S4 hetero-structured microspheres through the ion exchange method,and first used them in photocatalytic CO2 reduction in noble-metal-free systems.The activity results showed that these ZnIn2S4-CdIn2S4 photocatalysts exhibit excellent catalytic activity under visible light,and the best CO yield is as high as 33.57 μmol.h-1 with a selectivity of 91%.Furthermore,the stability and reusability of ZnIn2S4-CdIn2S4 was firmly confirmed by diverse characterizations,including X-ray diffraction (XRD),scanning electron microscopy (SEM),transmission electron microscopy (TEM),X-ray photoelectron spectroscopy (XPS),energy-dispersive X-ray spectroscopy (EDX) and N2 adsorption measurements.