物理化学学报 >> 2015, Vol. 31 >> Issue (9): 1715-1726.doi: 10.3866/PKU.WHXB201506231

电化学和新能源 上一篇    下一篇

固酶氮掺杂碳纳米复合物基燃料电池性能

库里松·哈衣尔别克,赵淑贤,杨阳,曾涵*()   

  • 收稿日期:2015-03-31 发布日期:2015-09-06
  • 通讯作者: 曾涵 E-mail:zenghan1289@163.com
  • 基金资助:
    国家自然科学基金(21363024);新疆师范大学博士科研启动基金(XJNUBS1228);新疆维吾尔自治区2013年度高校科研计划青年教师培育项目(XJEDU2013S29)

Performance of Nitrogen-Doped Carbon Nanocomposite with Entrapped Enzyme-Based Fuel Cell

HAYIERBIEK Kulisong,Shu-Xian ZHAO,Yang YANG,Han ZENG*()   

  • Received:2015-03-31 Published:2015-09-06
  • Contact: Han ZENG E-mail:zenghan1289@163.com
  • Supported by:
    the National Natural Science Foundation of China(21363024);Ph. D. Scientific Initiate Funding Project of XinjiangNormal University, China(XJNUBS1228);Xinjiang Autonomous Region 2013 Annual Colleges and Universities Scientific Research PlanYoung Teacher Cultivation Project, China(XJEDU2013S29)

摘要:

利用掺杂氮介孔材料(NDMPC)和羧甲基壳聚糖(CMCH)机械共混的纳米复合物作为固酶载体,以滴涂-干燥法分别制备了固定漆酶(Lac)阴极和固定葡萄糖氧化酶阳极,组装了有Nafion离子交换膜的葡萄糖/O2酶燃料电池.固定漆酶电极作为燃料电池阴极和氧电化学传感器的性能以结合旋转圆盘电极技术的循环伏安法、线性扫描伏安(LSV)法以及计时电流法进行表征,同时使用紫外-可见分光光度法和石墨炉原子吸收光谱法研究酶分子在电极表面的构型和估算电极表面载体对酶的担载量.测试结果表明:固酶阴极在无电子中介体时可以实现漆酶活性中心T1与导电基体之间的直接电子迁移(表观电子迁移速率为0.013 s-1),而且具有较小的氧还原超电势(150 mV).通过进一步定量比较分子内电子传递速率(1000 s-1)、底物转化速率(0.023 s-1)以及前述酶-导电基体间电子迁移速率,可以发现此电极催化氧还原循环受制于酶-电极之间的电子迁移过程;这种电极对氧的传感性能良好:低检测限(0.04 μmol·dm-3)、高灵敏度(12.1 μA·μmol-1·dm3)和良好的对氧亲和力(KM = 8.2 μmol·dm-3),这种固酶阴极还具有良好的重现性、长期使用性、热稳定性和pH耐受性.组装的生物燃料电池的开路电压为0.38 V,最大能量输出密度为19.2 μW·cm-2,最佳工作条件下使用3周后输出功率密度仍可保持初始值的60%以上.

关键词: 漆酶, 氮掺杂介孔碳材料, 羧甲基壳聚糖, 直接电子迁移, 氧还原反应, 电化学传感器, 生物燃料电池

Abstract:

A nanocomposite composed of N-doped mesoporous carbon material (NDMPC) and carboxymethylated chitosan (CMCH) was fabricated by mechanical co-mixing and used as an enzyme matrix. A novel glucose/O2 enzymatic biofuel cell was fabricated with a Nafion ion-exchange membrane consisting of a laccase (Lac)-entrapped biocathode and glucose oxidase-incorporated bioanode. Enzyme electrodes were prepared by the dripping coat and air-dried method. The performance of the laccase-based electrode as a biocathode in a fuel cell and an oxygen electro-chemical sensor was characterized by cyclic voltammetry in combination with the rotating disk electrode technique, linear scanning voltammetry (LSV), and chronoamperometry. UV-Vis spectrometry and graphite furnace atomic absorption spectroscopy were used to investigate the configuration of enzyme molecules on the surface of electrode and to evaluate the enzyme loading of the matrix on the electrode interface. The results from the experiments showed that the laccasebased cathode displayed direct electron transfer between the active centre in laccase (T1) and the conductive matrix without any external electron mediators (apparent electron transfer rate 0.013 s-1). A minor overpotential for oxygen reduction (150 mV) was also observed. Through further comparison of the intra-molecule electron relay rate (1000 s-1), substrate turnover frequency (0.023 s-1), and previous enzyme-conductive matrix electron transfer rate, quantitative analysis showed that the latter was the rate-determining step in the whole catalytic cycle of the oxygen reduction reaction. This laccase-based electrode as an oxygen electrochemical sensor for detecting oxygen showed a low detection limit (0.04 μmol·dm-3), high sensitivity (12.1 μA·μmol-1·dm3), and affinity for oxygen (KM = 8.2 μmol·dm-3). This laccase-based cathode also had advantages such as excellent reproducibility, long-term usability, thermal stability, and pH endurance. The results for the fabricated biofuel cell showed an open circuit voltage of 0.38 V and a maximal energy output density of 19.2 μW·cm-2, maintaining greater than 60% of the initial value even after continuous work for 3 weeks under optimal conditions.

Key words: Laccase, Nitrogen-doped meso-porous carbon material, Carboxymethylated Chitosan, Direct electron transfer, Oxygen reduction reaction, Electrochemical sensor, Bio-fuel cell