以硫酸亚铁铵为铁源和氮源,利用水热反应和冷冻干燥法制备了铁/氮掺杂的介孔还原氧化石墨烯气凝胶(FNGA)。采用扫描电镜(SEM)、X射线衍射仪(XRD)、比表面分析仪对材料结构进行表征;采用循环伏安法和交流阻抗法对其电化学性能进行研究。结果表明,与直接水热还原得到的石墨烯气凝胶相比较,铁/氮掺杂的石墨烯气凝胶不仅具有孔径在10~20μm之间的三维多孔结构,而且还具有10nm以下的介孔结构并且具有较高的比表面积,当其作为电极材料时可以为电解液中的小分子氧化还原反应提供更多反应位点,将其作为阳极材料应用于希瓦氏菌微生物燃料电池中后,显著提高了电池的放电功率密度与电流密度,电池的最大功率密度可达到10.94 W/m2。为开发低成本高效的微生物燃料电极阳极材料提供了新的思路。
Reduced graphene oxide(rGO)aerogel with three dimensional porous structure and highly biocompatibility is a kind promising electrode materials for fuel cells and super capacitors.The most often used method for rGO aerogel preparation are hydrothermal reduction but the raw product always possess hydrophobic surface that can't accessed by electrolyte as well as the bacteria cells in microbial fuel cells(MFCs).In this work,an iron decorated rGO with hierarchical porous structure was developed via freeze-drying assisted hydrothermal method.The ferrous and nitrogen doped rGO aerogel(FNGA)with optimized ratio was developed for MFC anode with ferrous ammonium sulfate as the Fe/N source.The FNGA possesses three dimensional hierarchical porous structure with mesopores,high specific surface area and hydrophilic surface,which deliver high redox peak current and lowest interfacial charge transfer resistance.When it is used in Shewanella putrefaciens MFC anode,the MFC achieves maximum power density of 10.94 W/m2,which is 1.8fold higher than GA anode.This work will provide a new strategy for developing high performance MFC anode materials.