功能化金刚石薄膜制备及其应用研究

【作者】 赵建文；

【导师】 只金芳；

【作者基本信息】 中国科学院研究生院（理化技术研究所） ， 物理化学， 2008， 博士

【摘要】 金刚石薄膜材料具有极高的稳定性、极高的硬度、较宽的禁带宽度、传播声波速度快、负电子亲和势、以及化学惰性等性质,使得金刚石薄膜材料在场发射、微电子器件、电化学、生物医用器件、表声波器件以及微机电一体化等方面有广泛的应用前景。作为新型碳素电极材料,高掺杂硼复合多晶金刚石薄膜具有许多目前使用的电极材料所不可比拟的优异特性,如宽电化学势窗,低背景电流,极好的电化学稳定性,表面不易被污染以及良好的生物兼容性。本文在金刚石薄膜可控制备、电化学性质、表面功能化修饰钯纳米粒子和氧化锌纳米棒等方面开展了如下工作:1通过控制反应室中的生长压力,得到不同粒径大小的金刚石薄膜。金刚石晶粒大小随生长压力减小而减小,当压力为725 Pa时,可以得到粒径约为20-30 nm的金刚石薄膜。相对于掺硼微米金刚石薄膜电极而言,掺硼纳米金刚石薄膜电极表现出更优越的电化学性质。2制得的掺硼纳米和微米金刚石薄膜电极,不需要进行任何修饰,在碱性条件下有干扰物质如抗坏血酸和尿酸存在时可对葡萄糖进行选择性检测。同时具有很高的灵敏度、较宽的线性范围、很好的稳定性和重复性。3结合光刻技术通过化学镀方法,在金刚石薄膜表面实现了铜、镍和金微图形化。得到的金属镀层非常均匀、致密,且与基体结合力强,同时不会对金刚石薄膜表面造成任何破坏。此外,该方法操作简单、不需要昂贵的仪器设备。4通过化学镀方法在巯基功能化的金刚石薄膜表面得到了一层银纳米叶薄膜,银纳米叶薄膜厚度随着沉积时间增加而增加。与此同时调查了银纳米叶薄膜拉曼性质,结果表明得到的银纳米叶薄膜相对于通过银镜反应和自组装得到的银膜具有更强的拉曼增强性质。5采用沉淀法在掺硼纳米金刚石薄膜电极表面修饰一层氧化锌纳米棒束,并通过氧化锌与低等电点蛋白质酪氨酸酶之间的静电作用力,把酶固定到电极表面,构建了酪氨酸酶传感器。利用该传感器检测了对甲基苯酚,得到了较好的实验结果。6通过种子诱导法在纳米金刚石表面得到氧化锌纳米棒阵列,然后通过共缩聚方法使氧化锌纳米棒表面生物功能化,再把探针DNA固定到功能化氧化锌纳米棒表面,制成DNA荧光传感器。该传感器具有较好的荧光增强效果以及稳定性。更多还原

【Abstract】 Owing to its chemical stability, high heat conductivity, negative or slight electron affinity, high phase velocity and excellent biocompatibility, diamond film, especially nanocrystalline diamond film, has recently come to be seen as the promising material for the high-efficiency electron emitters used in flat panel displays, conventional electronics applications, high frequency surface acoustic wave (SAW) devices, biomedical devices, microelectromechanical systems (MEMS) and so on. Furthermore, boron-doped diamond (BDD) thin-film electrodes have been regarded as attractive new electrode materials because of their properties including: 1) low and stable voltammetric background current, 2) wide working potential window in aqueous electrolyte solutions, 3) extreme electrochemical stability and high resistance to deactivation by fouling, 4) excellent biocompatibility, so the BDD electrodes are widely used for a variety of electrochemical and biological sensing applications. We have done the following research work based on the functional diamond films.1 Different size grain of diamond films are prepared by controlling the pressure of reaction chamber using hot filament chemical vapor deposition (HFCVD) method. The grain size decreases with decreasing the pressure of reaction chamber and boron-doped nanocrystalline diamond films are obtained at 725 Pa. Furthermore, the electrochemical behaviours of as-prepared electrodes are investigated, and the results show that boron-doped nanocrystalline diamond film electrodes exhibit excellenter electrochemical properites than those of boron-doped microcrystalline diamond film electrodes.2 It is find that glucose can be directly oxidized and selectively detected in the presence of ascorbic acid (AA) and uric acid (UA) on the as-prepared BDD electrode surfaces, and the nonenzymatic glucose sensor based on as-prepared BDD electrode shows high sensitivity, good reproducibility and stability.3 The compact and favorable copper, nickel and gold micropatterns are successfully fabricated on as-grown and amino-modification diamond substrates by electroless deposition in combination with lithography. The adhesion interaction between metal films and diamond substrates are so great that the metal films are not obviously changed after sonication for 15 min. In contrast to other methods, the proposed method is facile and need not the expensive apparatus.4 An approach for simultaneously synthesizing and immobilizing silver nanoleaves (SNLs) onγ-mercaptopropyltrimethyoxysilane (MPTS)-modified diamond thin film surface has been developed. The thickness of SNL layer deposited onto the CVD diamond substrate increases with increasing the deposition time. Furthermore, compared with self-assembled silver nanoparticle film and silver film from the mirror reaction, the SERS signal of R6G is obviously improved on the SNL films.5 An approach for depositing ZnO nanorod clusters on the nanocrystalline diamond film has been developed. Tyrosinase is firstly immobilized on ZnO nanorod clusters by electrostatic force, and then p-cresol is detected with the tyrosinase-modified electrode and good results are obtained.6 Micropatterned ZnO/SiO2 core/shell nanorod arrays are successfully fabricated on nanocrystalline diamond (NCD) film surfaces, and the performance as the fluorescence signal enhancing platform for DNA hybridization detection is also investigated. The use of ZnO/SiO2 nanorod arrays not only greatly enhance the fluorescence signal collected but also decrease the nonspecific adsorption effect of ZnO nanomaterials after carrying out hybridization reaction.更多还原