Background: Benzoic acid is widely applied in the food field, including beverages as the antimicrobial preservative due to its strong inhabitation role to bacteria and yeasts. However, excessive intake of benzoic acid can easily cause abdominal pain and diarrhea and can even result in metabolic diseases. Hence, it is important to seek simple, accurate and sensitive strategies to detect low-trace benzoic acid. Objective: The aim of this study is to synthesize dysprosium oxide/bismuth oxide nanocomposites using dysprosium sulphate and sodium bismuthate as the raw materials and research the electrochemical sensing properties for the detection of benzoic acid. Methods: Dysprosium oxide/bismuth oxide nanocomposites were synthesized by a facile hydrothermal route. The dysprosium oxide/bismuth oxide nanocomposites were characterized by X-ray diffraction, electron microscopy, X-ray photoelectron spectroscopy and electrochemical impedance spectroscopy. Results: The dysprosium oxide/bismuth oxide nanocomposites are composed of nearly circular-shaped particles with polycrystalline cubic Dy2O3 and triclinic Bi2O3 phases. The size of the nearly circular-shaped particles is about 50 to 200 nm. The electrons are easier to transfer by the dysprosium oxide/bismuth oxide nanocomposite-modified electrode than the bare electrode. A pair of quasi-reversible cyclic voltammetry (CV) peaks located at -0.155 V and -0.582 V exist in the CV curve of 0.1 M KCl buffer solution containing 2 mM benzoic acid. The nanocomposite-modified electrode shows a linear detection range and detection limit of 0.001-2 mM and 0.18 μM, respectively, for benzoic acid detection. Conclusion: The dysprosium oxide/bismuth oxide nanocomposite-modified electrode reveals superior electro-catalytic activity towards benzoic acid.

中文翻译：

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轻松合成具有良好电催化性能的氧化镝/氧化铋纳米复合电极材料

背景：苯甲酸因其对细菌和酵母菌有很强的抑制作用，作为抗菌防腐剂广泛应用于食品领域，包括饮料。但过量摄入苯甲酸很容易引起腹痛、腹泻，甚至引起代谢性疾病。因此，寻找简单、准确、灵敏的方法来检测低痕量苯甲酸非常重要。【摘要】：目的:以硫酸镝和铋酸钠为原料合成氧化镝/氧化铋纳米复合材料,并研究检测苯甲酸的电化学传感性能。方法：通过简便的水热路线合成氧化镝/氧化铋纳米复合材料。通过X射线衍射对氧化镝/氧化铋纳米复合材料进行了表征，电子显微镜、X射线光电子能谱和电化学阻抗谱。结果：氧化镝/氧化铋纳米复合材料由具有多晶立方Dy2O3和三斜Bi2O3相的近圆形颗粒组成。近圆形颗粒的尺寸约为50至200nm。与裸电极相比，氧化镝/氧化铋纳米复合材料修饰电极更容易传输电子。含有 2 mM 苯甲酸的 0.1 M KCl 缓冲溶液的 CV 曲线中存在一对位于 -0.155 V 和 -0.582 V 的准可逆循环伏安 (CV) 峰。对于苯甲酸检测，纳米复合材料修饰电极的线性检测范围和检测限分别为0.001-2 mM和0.18 μM。结论：