A novel nanocomposite, SnO₂/ZnS, was successfully synthesized via a one-step hydrothermal method. The composite was characterized by several techniques such as XRD, SEM, TEM, XPS and UV–vis spectrum, and utilized for photocatalytic degradation of refractory dye Rhodamine B (RhB) under simulated and natural sunlight. It was found that the composite prepared at the molar ratio of n(SnCl₄·5H₂O)/n(Zn(NO₃)₂·6H₂O) = 1.5 and hydrothermal temperature of 180 °C showed the highest photocatalytic activity. The photocatalytic degradation of RhB reached the maximum of 95% at the 1 g/L SnO₂/ZnS dosage, 10 mg/L initial RhB concentration, 4.59 initial solution pH and 23 °C. The RhB photocatalytic degradation fitted well to the first-order kinetics model, and the increased SnO₂/ZnS dosage, decreased initial RhB concentration and optimal initial solution pH were responsible for the increase of RhB photocatalytic degradation rate. The composite also displayed stable performance during 5 runs of reuse. Quenching tests demonstrated that the dominant active species generated in SnO₂/ZnS-RhB-H₂O-simulated sunlight system was O₂⁻; nevertheless, h⁺ and OH also contributed to RhB degradation. The formation mechanism of the SnO₂/ZnS nanosphere and RhB photocatalytic degradation mechanism were proposed. Moreover, the composite has proved to have the high efficiency for the degradation of RhB under natural sunlight irradiation.

中文翻译：

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在模拟和自然光下水热合成SnO ₂ / ZnS纳米复合材料作为光催化降解罗丹明B的光催化剂

通过一步水热法成功合成了新型纳米复合材料SnO ₂ / ZnS。该复合材料通过XRD，SEM，TEM，XPS和UV-vis光谱等多种技术进行了表征，并在模拟和自然日光下用于光催化降解难降解染料若丹明B（RhB）。发现以n（SnCl ₄ ·5H ₂ O）/ n（Zn（NO ₃）₂ ·6H ₂ O）= 1.5的摩尔比制备的复合材料具有180℃的水热温度，具有最高的光催化活性。在1 g / L SnO _2下，RhB的光催化降解达到最大95％/ ZnS剂量，10 mg / L初始RhB浓度，4.59初始溶液pH和23°C。RhB光催化降解与一级动力学模型非常吻合，增加SnO ₂ / ZnS用量，降低初始RhB浓度和最佳初始溶液pH值是RhB光催化降解速率增加的原因。在5次重复使用期间，该复合材料还显示出稳定的性能。淬火的测试表明，以SnO产生的占主导地位的活性种₂ /的ZnS-罗丹明B-H ₂ O形模拟太阳光系统使用邻₂ ^- ; 然而，h ⁺和OH也会导致RhB降解。SnO ₂的形成机理提出了/ ZnS纳米球和RhB光催化降解机理。此外，已证明该复合物具有在自然阳光照射下降解RhB的高效率。