碳纳米管和镍共修饰BDD电极及其在非酶葡萄糖电化学传感器中的应用

Carbon Nanotubes and Nickel Co-modified BDD Electrodes and Their Application for Non-enzymatic Glucose Electrochemical Sensor

目的制备碳纳米管-镍/掺硼金刚石复合电极(CNTs-Ni/BDD),并用于非酶葡萄糖电化学检测。方法采用热丝化学气相沉积(HFCVD)在硅基体上沉积BDD,然后采用物理气相沉积(PVD)技术在BDD上沉积Ni薄膜,最后在管式炉中对Ni/BDD样品进行900℃热催化处理,调控热处理时间分别为30、90 min,得到不同微观结构的CNTs-Ni/BDD复合电极。采用扫描电子显微镜(SEM)、Raman光谱和电化学工作站分别表征电极的表面形貌、成分和电化学性能。结果在Ni的高温催化作用下,BDD作为基体和唯一碳源,在其表面直接生长出CNTs,实现Ni纳米颗粒和CNTs共修饰BDD。热处理时间由30 min增加到90 min,CNTs长度明显增加,对BDD的覆盖程度增加,且顶端的Ni颗粒消失。CNTs和Ni的共修饰作用极大地提升了葡萄糖的电化学检测性能,且30min-CNTs-Ni/BDD复合电极性能更优异,其灵敏度在葡萄糖浓度0.005~0.02mmol/L、0.02~1mmol/L、1.0~5.5mmol/L线性范围内分别为475、42、19μA/((mmol/L)·cm2),检测限为0.42μmol/L(S/N=3)。结论热催化处理可以简单高效地实现CNTs、Ni共修饰BDD,该复合电极能够有效地提升葡萄糖电化学检测性能。

The work aims to prepare carbon nanotube-nickel/boron-doped diamond composite electrode(CNTs-Ni/BDD)and use it in non-enzymatic glucose electrochemical detection.Hot filament chemical vapor deposition(HFCVD)was adopted to deposit BDD on silicon substrate and physical vapor deposition(PVD)was used to deposit Ni film on BDD.Then the Ni/BDD samples were put into a tube furnace for heat treatment at 900℃for 30 min and 90 min respectively,to obtain CNTs-Ni/BDD electrodes with different microstructures.The surface morphology,composition and electrochemical performance of the films were characterized with scanning electron microscope(SEM),Raman spectroscope and electrochemical workstation,respectively.Finally,the CNTs grew from BDD directly with BDD as the substrate and the only carbon source at the high-temperature catalyst of Ni to modify BDD by Ni nano-particles and CNTs.In addition,if the heating time was increased from 30 min to 90 min,the length of CNTs increased significantly,the coverage degree on BDD improved and the Ni nano-particles disappeared.The joint modification of CNTs and Ni significantly improved the electrochemical detection performance of glucose.The 30 min-CNTs-Ni/BDD composite electrode showed a superior electrochemical performance and the sensitivity in the linear ranges of glucose concentration of 0.005~0.02 mmol/L,0.02~1 mmol/L and 1.0~5.5 mmol/L was 475,42,and 19μA·(mmol/L)?1·cm?2,correspondingly.In addition,the detection limit was 0.42μmol/L(S/N=3).The heat treatment can simply and effectively prepare a CNTs-Ni/BDD composite electrode which can effectively improve the electrochemical detection performance of glucose.