一种含铜固体电极在新型无膜生物电化学系统中的应用研究

采用壳聚糖修饰电极吸附溶液中Cu(Ⅱ)制得含铜固体电极,将其用做新型无膜生物电化学系统(MACMCB)阴极。研究固体电极Cu(Ⅱ)质量和外阻对MACMCB电压的影响。结果表明,系统电压与含铜固体电极Cu(Ⅱ)质量及系统外阻正相关,最大输出电压达0.6346 V。该系统Cu(Ⅱ)还原效率高于92.75%,表明Cu(Ⅱ)做电子受体得电子能力强,Cu(Ⅱ)几乎被全部还原。MACMCB与微生物燃料电池(MFC)的效率对比结果表明,在一定时间内,MACMCB在底物降解效率和产能输出方面明显优于MFC,推荐含铜固体电极更换时间为10~30小时。含铜固体电极中Cu(Ⅱ)主要以Cu SO4分子形式存在,放电后Cu(Ⅱ)的主要还原产物为单质Cu,含少量Cu2O,另外掺杂部分Cu元素的磷化物和氯化物沉淀。

Solid Electrodes with Cu(Ⅱ) Applied in Free-membrane Bioelectrochemical System

A solid electrode with Cu(Ⅱ) was prepared by utilizing chitosan modified electrode to adsorb Cu(Ⅱ) in the solution, which was used as the cathode of microbial anode and chitosan modified cathode based battery (MACMCB). Different Cu(Ⅱ) masses and external loadings were tested to study the discharge property of MACMCB system. Results indicate that better discharge process relies on a larger amount of Cu(Ⅱ) or a higher external loading in this work. The highest cell voltage is 0.6346 V. The Cu(Ⅱ) reduction efficiency of MACMCB system is higher than 92.75%, indicating a nearly complete reduction of Cu(Ⅱ). The comparison between MACMCB and MFC indicates that MACMCB showes better performance than MFC on substrate consume and electricity output within a period of time. Changing the solid electrode within 10- 30 hours is recommended. CuSO4 is directly adsorbed inside the solid electrode. The major reduction product is copper, while the left included Cu2O, phosphide of copper and chloride of copper.