Abstract A novel 3D straw-bundle-like Mn-La oxides/reduced graphene oxide composite (Mn-La oxides/rGO) has been successfully synthesized by a facile thermal evaporation method. The products were investigated by means of scanning electron microscopy (SEM), energy dispersive X-ray spectrum (EDS), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electrochemical method. The possible growth mechanism was tentatively proposed. The application of the 3D straw-bundle-like Mn-La oxides/rGO as electrode-modified material for electrochemical oxidation of L-cysteine was studied. The prepared Mn-La oxides/rGO modified electrode expressed prominent electrocatalytic ability for the electrochemical oxidation of L-cysteine. Under optimum experimental conditions, the current response of L-cysteine were linear with its concentration in the range of 0.5–832.5 μM with a low detection limit of 0.1 μM (S/N = 3). The proposed sensor was used to evaluate its application for the detection of L-cysteine in the real samples.

中文翻译：

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基于分层3D稻草束状Mn-La氧化物/还原氧化石墨烯复合材料的高性能电化学L-半胱氨酸传感器

摘要 通过简便的热蒸发方法成功合成了一种新型 3D 秸秆束状 Mn-La 氧化物/还原氧化石墨烯复合材料（Mn-La 氧化物/rGO）。通过扫描电子显微镜（SEM）、能量色散X射线光谱（EDS）、X射线粉末衍射（XRD）、X射线光电子能谱（XPS）和电化学方法对产物进行了研究。初步提出了可能的增长机制。研究了 3D 秸秆束状 Mn-La 氧化物/rGO 作为电极修饰材料在 L-半胱氨酸电化学氧化中的应用。制备的Mn-La氧化物/rGO修饰电极对L-半胱氨酸的电化学氧化表现出显着的电催化能力。在最佳实验条件下，L-半胱氨酸的电流响应与其浓度在 0.5–832.5 μM 范围内呈线性关系，检测限低至 0.1 μM (S/N = 3)。所提出的传感器用于评估其在实际样品中检测 L-半胱氨酸的应用。