环糊精调制杂化石墨烯双重电子转移网络酶电极及其燃料电池的性能

In recent years, considerable interest has focused on the development of enzymatic biofuel cells (EBFC) because they can act as an in-vivo power source for implantable medical devices such as pacemakers, micro drug pumps, and deep brain stimulators, etc. The most attractive feature of these EBFC is that they can utilize glucose or other carbohydrates abundantly presented in the human body as a fuel. Until now, numerous efforts among many researchers have aimed at fabricating practical EBFC devices by different theoretical concepts. However, low power density and short lifetime of EBFC are the two major challenges in practical applications. Thus, to seek a proper methodology for enzyme immobilization on the EBFC electrode is the key strategy to overcome above-mentioned disadvantages. Accordingly, we propose a three-dimension electrode architecture which could provide indirect/direct binary electron transfer mechanism by Layer-by-Layer assembly (LbL) using three ingredients, including (1)direct electron transfer layer of gold hybrid graphene (Au@rGC), built by self-assembly of reduced graphene oxide, cyclodextrin and gold precursor, (2)indirect electron transfer layer of cyclodextrin-ferrocene inclusion complex (CFc), and (3)assembly of cyclodextrin and enzyme (EnC). Enzymatic electrode network ([Au@rGC-CFc-EnC]n/GCE) is constructed by depositing Au@rGC, FrMC and EnC on glass carbon electrode(GCE) sequentially through LbL route, and the final structure is crosslinked by glutaraldehyde. The micro-structure and micro-environment of three-dimension electrode can be tuned conveniently by controlling the structure of each assembling component combined with the depositing process of enzymatic electrode to achieve indirect/direct binary electron transfer mechanism and extend lifetime of enzymatic cell, in which the properties of assembling components as well as depositing process can be controlled by the functional groups of cyclodextrin. The constructed enzymatic electrode should possess a high efficiency of electron transfer and longer stability. The strategy that we proposed will open up a new potential way for the realization of practical enzymatic biofuel cell applications. In addition, the proposal could facilitate the application in sensor, analytical chemistry, and the enzymatic catalyst in industry.

酶生物燃料电池（EBFC）是一种可再生、绿色能源，但其输出功率密度低、寿命短等问题是其应用的瓶颈。本项目提出利用纳米金杂化石墨烯（Au@rGC）、二茂铁等通过层层组装方法构筑具有直接与间接电子转移双重导电机制的三维立体网络酶电极，利用环糊精的多重自组装特性及生物相容性调控酶电极的微结构与酶的微环境，提高电池功率密度并延长其寿命。重点探讨电极组装组成：Au@rGC、环糊精包合二茂铁（CFc）、环糊精与酶的组装体（EnC）的形成机制；揭示各组成性能、组装工艺等对酶电极[Au@rGC-CFc-EnC]n/GCE微观结构与性能的影响规律；通过调整环糊精上取代基的结构与自组装特性，实现对Au@rGC、CFc及EnC的组成、电极导电网络微结构与环境的调控；探讨酶电极网络组成、结构等对酶电极及其电池性能的影响规律，获得兼具高电子转移效率与长寿命的酶电极，为高功率、长寿命EBFC的工程化应用奠定理论基础。

酶生物燃料电池（EBFC）是一种可再生绿色新能源，但其电子传递效率差、输出功率密度较低、循环稳定性差等问题是其应用的瓶颈。.本项目利用环糊精调制导电纳米杂化还原氧化石墨烯改善电极的直接电子传导性；利用环糊精与二茂铁的主客体作用，改善电极的间接电子传导性，构筑具有直接-间接双重电子传递机制的酶电极，分析了该电极电子传递机制及其对葡萄糖的电催化性能，发现该双重电子传递通道的电子传递效率明显高于同一条件下的单一直接电子传递通路，构筑的酶电极对葡萄糖的电化学性能较优。利用电化学聚合和电化学沉积的方法制备了电聚合环糊精/电沉积纳米金电极，发现该电极对葡萄糖和多种生物质的选择性检测性能优良。.探索了静电吸附、包埋法等酶的固定方法及其对酶电极性能的影响规律，发现利用适当的阳离子表面活性剂（十八烷基三甲基溴化铵，STAB）产生的静电吸附的方法固定酶电极性能比包埋法固定酶电极的开路电压高、循环性能稳定，可以实现葡萄糖氧化酶与漆酶的有效固定，为组装开路电压较高、性能稳定的双酶燃料电池奠定基础；通过巯基共价结合酶制备纳米金复合酶电极，获得的酶电极的最大输出功率达2.84±0.09 mW cm-2，该酶燃料电池在室温条件下持续运行70天，最大输出功率可保持85.5%；利用静电纺丝聚丙烯腈螯合定向固定漆酶，可以在泡沫镍基底上构筑载酶量大、长期稳定性优异的漆酶电极。.利用三维泡沫镍为基底，构筑导电性良好的纳米粒子，并利用共价固定、定向固定的方法分别固定葡萄糖氧化酶及漆酶，进而构建全酶燃料电池。分析发现，全酶燃料电池的开路电压(OCV)约为0.66 V，在0.15 V处呈现的最大输出能量密度大约是1.53mW cm-2。.另外，我们还研究了所构筑电极的传感性能，发现适当控制电极的表面结构，可以构筑灵敏度高、检出限低、线性范围好的传感器。探索了光响应电极的制备、结构与性能、刺激响应酶电极的构筑与性能等相关工作。.本项目的研究为酶生物燃料电池及相关传感器的应用奠定了基础；项目设计的导电性能良好的纳米电极的构筑方法、酶的定向固定方法等对相关领域的研究与应用也具有一定的借鉴价值。发表学术论文15篇，SCI 收录 13 篇；申请发明专利4件，获得授权1 件。