静电纺丝法制备高熵合金及其蔬果中重金属离子电化学传感应用

Preparation of High-Entropy Alloy by Electrospinning and Its Application in Electrochemical Sensing for Detection of Heavy Metal Ions in Vegetables and Fruits

采用静电纺丝结合高温石墨化技术,以静电纺丝碳纳米纤维(carbon nanofibers,CNFs)串联多金属,再通过高温石墨化技术成功在碳纳米纤维上原位合成了均一的高熵合金纳米颗粒(high-entropy alloy nanoparticles,HEA NPs)。基于FeCoNiCrCe/CNFs构建的重金属离子电化学传感器能实现同时对3种重金属离子的灵敏检测。在pH 5的0.1 mol/L醋酸-醋酸钠缓冲液中,沉积电压和时间分别为-1.3 V和300 s条件下,本研究所构建的电化学传感器对Cd^(2+)、Pb^(2+)和Cu^(2+)的检测限分别为0.06、0.005μmol/L和0.005μmol/L(信噪比=3)。分析认为其优异的性能归因于特定的HEANPs提供了良好的导电性和催化活性,以及CNFs较高的比表面积暴露出更多活性位点,二者的协同作用有利于重金属离子的吸附和脱附,促进了重金属离子的氧化还原反应以及电荷转移。本研究所制备的FeCoNiCrCe/CNFs/GCE电化学传感器在蔬果中检测重金属离子领域具有一定应用前景。

In this study,electrospinning was used to connect carbon nanofibers(CNFs)with multiple metals.Then,through high-temperature graphitization technology,uniformly sized high-entropy alloy nanoparticles(HEA NPs)were successfully synthesized in situ on CNFs.An electrochemical sensor for the simultaneous and sensitive detection of three heavy metal ions was fabricated based on FeCoNiCrCe/CNFs.In 0.1 mol/L acetic acid-sodium acetate buffer solution at pH 5,at deposition voltage and time of-1.3 V and 300 s,respectively,the limits of detection(LOD)of the electrochemical sensor were 0.06,0.005 and 0.005μmol/L(signal-to-noise ratio=3)for Cd^(2+),Pb^(2+),and Cu^(2+),respectively.The excellent performance was considered to be attributed to the good conductivity and catalytic activity provided by HEA NPs and the higher specific surface area of CNFs exposing more active sites,which were synergistically conducive to the adsorption and desorption of heavy metal ions,thereby promoting the redox reaction and charge transfer of heavy metal ions.The FeCoNiCrCe/CNFs/GCE electrochemical sensor prepared in this study has promising application prospects in the detection of heavy metal ions in vegetables and fruits.