Sari Trisna K, Takahashi Fumiki, Jin Jiye, Zein Rahmiana, Munaf Edison
Department of Chemistry, Faculty of Science, Shinshu University.
Department of Chemistry, Faculty of Mathematics and Natural Science, Andalas University.
Anal Sci. 2018;34(2):155-160. doi: 10.2116/analsci.34.155.
In this study, nanocomposites of ligand-free gold nanoparticles that are anchored onto the graphene surface (Graphene/AuNPs) were synthesized by a sonochemical method in a single reaction step. A highly sensitive amperometric sensor using Graphene/AuNPs is proposed for the determination of trace hexavalent chromium Cr(VI) in environmental water samples. Compared with a gold electrode, a glassy carbon electrode and a AuNPs modified glassy carbon electrode, the Graphene/AuNPs modified glassy carbon electrode exhibits the highest electrocatalytic activity and stability towards the reduction of Cr(VI), based on the results by cyclic voltammetry and electrochemical AC impedance studies. This study shows that the Graphene/AuNPs-based sensor can detect Cr(VI) with a low detection limit of 10 nM (∼0.5 μg/L), a wide dynamic range of 0 to 20 μM (R = 0.999) and very good selectivity and reproducibility. The electrode is applied to the determination of Cr(VI) in river samples with satisfactory recovery values.
在本研究中，通过声化学方法在单一反应步骤中合成了锚定在石墨烯表面的无配体金纳米颗粒的纳米复合材料（石墨烯/金纳米颗粒）。提出了一种使用石墨烯/金纳米颗粒的高灵敏度安培传感器，用于测定环境水样中的痕量六价铬Cr(VI)。循环伏安法和电化学交流阻抗研究结果表明，与金电极、玻碳电极和金纳米颗粒修饰的玻碳电极相比，石墨烯/金纳米颗粒修饰的玻碳电极对Cr(VI)的还原表现出最高的电催化活性和稳定性。本研究表明，基于石墨烯/金纳米颗粒的传感器能够检测Cr(VI)，检测限低至10 nM（约0.5 μg/L），动态范围宽达0至20 μM（R = 0.999），并且具有非常好的选择性和重现性。该电极用于测定河流样品中的Cr(VI)，回收率令人满意。
