中文摘要：

微生物燃料电池是一种可以从污水中直接回收能量的新型装置。然而，相对低的输出功率密度严重限制了它的应用。阳极材料对于提高其功率密度和能量转换效率至关重要。本文利用一步碳化法基于农业废弃物木薯秸秆制备了先进的三维多孔碳阳极，用扫描电子显微镜观察了所制备的材料的形貌，发现其内部呈现天然筛管式大孔结构，可有利于增大阳极生物负载量和优化传质作用。利用交流阻抗谱、循环伏安技术以及双室微生物燃料电池结构研究了材料的电化学性能，结果发现，800℃下碳化得到的三维多孔碳具有最优的电化学活性和最佳功率输出，其最大功率密度高达73.0W/m3，是商业碳纸的3.7倍。此研究为构筑高效生物化学体系电极材料提供了新思路和新方法。

英文摘要：

Microbial fuel cells(MFCs)are emerging as an energy conversion device to directly harvest electricity energy from wastewater,of which the power density is relative low,which limited its applications to a great degree.The anode material is crucial for the improvement of power density and the energy conversion efficiency of MFCs.In this study,an advanced three-dimensional(3D)carbon anode with macropore structure was obtained by the one-step carbonization of cassava straws which are agricultural solid residues.The morphology of the3D porous carbon(3DPC)was observed using scanning electron microscope(SEM).The results showed that the3DPC consists of sieve-like tube structure with macropore,which is beneficial for biomass loading and mass transfer.The electrochemical performance of the3DPC was measured by electrochemical impedance spectroscopy(EIS),cyclic voltammetry(CV)as well as dual-chamber microbial fuel cells(MFCs)device.It was found that the3DPC obtained at800℃had the best electrochemical activity,and the highest power density was as high as73.0W/m3,which was3.7-fold higher than that of commercial carbon paper.This study provided new ideas and methods for the construction of highly efficient biochemical system electrode materials.