Abstract A novel 3D prickly ball-like Co–La oxides/reduced graphene oxide composite (Co–La oxides/rGO) has been successfully synthesized by a facile thermal evaporation method. Co–La oxides were hierarchical spiny globular structure made up of numerous radially-grown nanowires with the size of about 50 nm in width. Some of the nanowires grow vertically on the surface of rGO nanosheets. GO was thermally reduced to rGO. XPS data showed that the Co3+, Co2+ and La3+ existed in the prepared samples. The possible growth mechanism was tentatively proposed. The application of the 3D prickly ball-like Co–La oxides/rGO as electrode-modified material for electrochemical oxidation of l -cysteine was studied. The prepared prickly ball-like Co–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 1.0–888.0 μM with a low detection limit of 0.1 μM (S/N = 3). The 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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用于l-半胱氨酸电化学传感的分层3D刺球状Co-La氧化物/还原氧化石墨烯复合材料的制备

摘要 通过简便的热蒸发方法成功合成了一种新型 3D 刺球状 Co-La 氧化物 / 还原氧化石墨烯复合材料（Co-La 氧化物 / rGO）。Co-La 氧化物是由许多直径约 50 nm 的径向生长的纳米线组成的分级多刺球状结构。一些纳米线在 rGO 纳米片的表面垂直生长。GO 被热还原为 rGO。XPS 数据表明制备的样品中存在 Co3+、Co2+ 和 La3+。初步提出了可能的增长机制。研究了 3D 刺球状 Co-La 氧化物/rGO 作为电极改性材料用于 l-半胱氨酸电化学氧化的应用。制备的刺球状Co-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 1.0–888.0 μM 范围内呈线性关系，低检测限为 0.1 μM (S/N = 3)。该传感器用于评估其在实际样品中检测 l-半胱氨酸的应用。