【作者】 陈建；

【导师】 王艳；

【作者基本信息】 中南大学 ， 制药工程， 2014， 硕士

【摘要】 本论文以二氧化钛纳米管阵列作基底材料,在其表面负载纳米铂颗粒,制备一种新颖的无酶葡萄糖传感器。二氧化钛纳米管阵列采用阳极氧化法合成,为平行整齐直立排列的二氧化钛纳米管,其比表面积大,耐热耐酸碱,机械性能好,具有光催化降解能力,是一种很好的载体材料；铂颗粒采用离子交换法原位负载于二氧化钛上,铂颗粒粒径为5nm,比表面积大,分散均匀,催化活性高。制备的铂／二氧化钛复合纳米材料电极对葡萄糖表现了很好的催化活性,电化学检测电位负(-0.5V vs.SCE),同时电极具有自清洁能力,为开发新型无酶葡萄糖传感器提供了一种新的可能,对于血糖浓度的检测和作为葡萄糖燃料电池的阳极具有很好的应用前景。制备了两种类型的电极：一次煅烧法电极采用阳极氧化法制备二氧化钛纳米管阵列作为载体材料,空气煅烧3h,碱-酸处理,以二氯四氨合铂为铂的前驱体,采用离子交换法将其负载于二氧化钛纳米管表面,经NaBH4还原,制备铂/二氧化钛电极。采用扫描电镜(SEM)表征二氧化钛形貌,管径为200nm,管长4μm；采用透射电镜(TEM)表征纳米铂颗粒的负载情况,纳米铂颗粒在二氧化钛基底上负载均匀,粒径为5nm；X-射线衍射仪(XRD)表征二氧化钛的晶型,阳极氧化的二氧化钛为无定型,煅烧后二氧化钛晶型为锐钛矿型；X-射线光电子能谱仪(XPS)表征铂的价态,还原后铂的价态为零价；对铂/二氧化钛电极进行电化学性能检测,电化学检测电位为-0.5V (vs. SCE),灵敏度为63.77μA·mM-1·cm-2,检测限为0.2mM (S/N=3),线性范围为1-15mM,0.1mM尿酸对1mM葡萄糖的干扰为0.2%,0.1mM抗坏血酸的干扰为6.7%(电流比),对1mM葡萄糖溶液经过两个星期的定时检测,检测电流值下降3%,电极具备很好的稳定性。二次煅烧法电极采用阳极氧化法制备二氧化钛纳米管阵列作为载体材料,N2煅烧3h,碱-酸处理,以二氯化四氨合铂为铂的前驱体,采用离子交换法将其负载于二氧化钛纳米管表面,再一次N2煅烧3h,经NaBH4还原,制备铂／二氧化钛电极。SEM, TEM, XRD, XPS表征与一次煅烧法电极类似。制备的电极进行电化学性能检测,检测电位为-0.4V (vs. SCE),灵敏度为1.01386E-4A·mM-1·cm-2,检测限为0.2mM (S/N=3),线性范围为0.5-4.5mM,0.1mM尿酸对1mM葡萄糖的干扰为0.93%,0.1mM抗坏血酸的干扰为4.99%(电流比),对1mM葡萄糖溶液经过两个星期定时检测,电流值下降2.22%。同时对葡萄糖在电极表面电催化氧化机理进行研究,氧化峰电流与扫速的平方根成正比,证明葡萄糖在电极表面的反应为扩散控制；葡萄糖在电极上发生两质子-两电子转移反应；并采用交流阻抗法对电极进行了详细的自清洁过程的研究,证明铂/二氧化钛电极具有很好的光-电催化自清洁能力,保证了电极电催化氧化葡萄糖的性能。更多还原

【Abstract】 In this paper, a novel non-enzymatic glucose sensor was developed based on TiO2nanotube array as a substrate material and loading Pt nanoparticles on TiO2nanotube array (NTA). The regular orientation perpendicular TiO2NTA was prepared by method of anodization with properties of containing large specific surface area, thermal and acid-base tolerance and photocatalytic degradation ability, being a excellent suppoting material. The Pt particles were loaded on TiO2in situ by ion-exchange and the particle size of Pt was5nm with large specific surface area and high catalytic activity. Pt/TiO2NTA composite electrode showed high catalytic activity to glucose, negative detection potential (-0.5V vs. SCE)and highly self-cleaning ability, which provides a new possibility for developing new glucose sensors and has promising applications in blood glucose measurement and meidiator-free anodes for glucose biofuel cells.Two kinds of non-enzymatic glucose sensors were fabricated:One-time calcination electrode was developed based on TiO2NTA as supporting material prepared by anodizaton, calcined for3h in air atmosphere and treated by base-acid. Pt(NH3)4Cl2, as the Pt precursor, was ion-exchanged on the TiO2nanotube surface and reduced by NaBH4and the Pt/TiO2electrode was prepared well. SEM was carried out to investigate TiO2NTA morphology. The results of SEM show that the tube diameter and length were200nm and4um; TEM was carried out to investigate the Pt nanoparticles dispersion, of which the results demonstrate that the Pt nanoparticles uniformly deposited on TiO2surface with average grain size of5nm. XRD was used to characterzize TiO2crystal form. The anodized TiO2was amorphous, while the calcined TiO2was anatase. XPS was performed to investigate the valence state of Pt, of which the results showed that the deposited Pt was zero valent. The Pt/TiO2electrode can detect glucose at an applied potential of-0.5V(vs. SCE) with a linear range of1-15mM, a sensitivity of63.77μA·mM-1· cm-2and a detection limit of0.2mM at a signal-to-noise ratio of3. The interfering current ratio of0.1mM uric acid (UA) was0.2%, while that of0.1mM ascorbic acid (AA) was6.7%; The current response of1mM glucose only decreased by3%after2weeeks of regular measurements, showing good stability.Two-time calcination electrode was developed based on TiO2NTA as supporting material prepared by anodizaton, calcined for3h in N2atmosphere and treated by base-acid. Pt(NH3)4Cl2, as the Pt precursor, was ion-exchanged on the TiO2nanotube surface and subsequently calcined for3h in N2atmosphere again and finally reduced by NaBH4, and the Pt/TiO2electrode was prepared well. SEM, TEM, XRD, XPS characterizations were the same to that of above. The Pt/TiO2electrode can detect glucose at an applied potential of-0.4V(vs. SCE) with a linear range of0.5-4.5mM, a sensitivity of1.01386μ·AmM-1·cm-2and a detection limit of0.2mM (S/N=3). The interfering current ratio of0.1mM UA was0.93%and that of0.1mM AA was4.99%; The current response to1mM glucose only decreased by2.22%after2weeeks of regular measurements. Meanwhile, glucose electrocatalytic oxidation mechanism on the surface electrode was investigated. The oxidation peak current linearly increased with the square root of the scan rate, which indicated that the electrode reaction of glucose was a typical diffusion-controlled process. The glucose electrocatalytic oxidation was two-electron and two-proton process. The electrochemical impedance spectroscopy was carried out to detailed self-cleaning process research, of which the result indicated Pt/TiO2electrode contained the excellent photoeletrocatalysis ability and ensured the electrocatalytic oxidation ability of electreode to glucose.更多还原