Abstract Metal oxide/graphene composite has become a promising electrode material to improve the performance of electrochemical sensor. Here SnO2 decorated graphene (SnO2-RGO) composite was facilely fabricated by a hydrothermal reduction of graphene oxide with SnCl2, and applied as active electrode material into constructing electrochemical sensor for caffeic acid (CA). The SnO2-RGO composite was characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The electrochemical sensor (SnO2-RGO/GCE) obtained from SnO2-RGO coating of glass carbon electrode showed excellent electrocatalytic performance for the redox reaction of CA. A linear range of 0.15–25 μM and a detection limit of 80 nM (S/N = 3) were achieved in 0.1 M phosphate buffer (pH 7.0). The present electrochemical sensor also showed high selectivity for CA, excellent reproducibility and stability. Eventually, the sensor SnO2-RGO/GCE was successfully applied for CA detection in commercial red wine samples with satisfactory recovery results.

中文翻译：

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SnO2修饰石墨烯复合材料的制备及其在红酒中咖啡酸电化学检测中的应用

摘要 金属氧化物/石墨烯复合材料已成为一种很有前景的电极材料，可提高电化学传感器的性能。在这里，SnO2 装饰的石墨烯（SnO2-RGO）复合材料是通过用 SnCl2 对氧化石墨烯进行水热还原而制备的，并将其作为活性电极材料应用于构建咖啡酸（CA）的电化学传感器。通过 X 射线光电子能谱 (XPS)、X 射线衍射 (XRD) 和透射电子显微镜 (TEM) 对 SnO2-RGO 复合材料进行表征。从玻璃碳电极的 SnO2-RGO 涂层获得的电化学传感器 (SnO2-RGO/GCE) 对 CA 的氧化还原反应显示出优异的电催化性能。在 0.1 M 磷酸盐缓冲液 (pH 7.0) 中实现了 0.15–25 μM 的线性范围和 80 nM (S/N = 3) 的检测限。本电化学传感器还显示出对 CA 的高选择性、优异的重现性和稳定性。最终，传感器 SnO2-RGO/GCE 成功应用于商业红葡萄酒样品中的 CA 检测，回收率结果令人满意。