Facile synthesis of Sb2S3/ultrathin g-C3N4 sheets heterostructures embedded with g-C3N4 quantum dots with enhanced NIR-light photocatalytic performance

In recent years, exploiting novel photocatalysts with a broad range of wavelengths photoresponse is undoubtedly interesting in photocatalytic field. Here, a novel Sb2S3/ultrathin g-C3N4 sheets heterostructures embedded with g-C3N4 quantum dots (CNS) was successfully fabricated via a facile hydrothermal process. The samples were systematically characterized by the field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV–vis-NIR diffuse reflection spectroscopy (UV-vis-NIR DRS) and photoluminescence (PL) spectroscopy. It is indicated that the composites have fast electron transport and enhanced solar light absorption. Moreover, the CNS composite exhibits a significant photoelectric conversion property in near-infrared (NIR) wavelength range. The photocatalytic activities of the samples were evaluated by the degradation of methyl orange (MO) upon NIR irradiation. The photodegradation rate of the optimal CNS for MO was 0.0103 min−1, about 2.6 times higher than that of pure Sb2S3. The improved NIR photocatalytic activity may base on the improved absorption in the NIR region, efficient electron-hole separation and the up-converted PL property of g-C3N4 quantum dots (CNQD).