百香果内膜生物炭作为微生物燃料电池阴极催化剂的产电性能研究

摘要

Biochar nano-sheets ( BXG-AC) with high surface area and porous structure were prepared by direct pyrolysis of the inner membrane of passion fruit and subsequent KOH activation. The morphology and surface elemental composition of BXG-AC were characterized by scanning electron microscopy ( SEM ) and X-ray photoelectron spectroscopy ( XPS ) and the electrochemical behaviors were investigated by cyclic voltammetry and linear sweep voltammograms ( LSV) . The results indicate that in neutral media, the as-prepared BXG-AC catalyst exhibits remarkable electrocatalytical activity;a maximum power density of 1153. 3 mW/m2 is achieved in the microbial fuel cells ( MFCs), which is comparable to that of commercial Pt/C (1214. 3 mW/m2 ). Furthermore, the BXG-AC cathode also displays a great long-term stability; the MFC output decreases slightly after operation for more than 60 cycles. This study demonstrates that the biochar nano-sheets derived from the inner membrane of passion fruit is probably a cost-efficient and promising cathodic catalyst for the scale-up MFCs.%以天然来源的生物质百香果内膜为原料,采用热解炭化-KOH活化的方法制备出比表面积大、孔隙结构好的纳米片生物炭(BXG-AC),并通过扫描电子显微镜(SEM)、X射线光电子能谱(XPS)等方法对所制备催化剂进行了元素组成和微观形貌表征,采用循环伏安扫描(CV)和线性伏安扫描(LSV)对材料的电化学性能进行分析.结果表明,百香果内膜生物炭经过KOH活化后,在0.1 mol/L的磷酸缓冲液(PBS)中表现出良好的电催化活性.将所制备的催化剂应用于单室MFCs阴极时,对应的MFC最大功率密度达1153.3 mW/m2,略低于Pt/C的1214.3 mW/m2,且此MFC运行60 d后,其性能未见明显降低.表明BXG-AC催化剂具有显著的催化活性和稳定性,为开发高效MFC阴极催化剂提供了新途径.