Reduced graphene oxide aerogels (RGOAs) were obtained through steam reduction of freeze-dried graphene oxide hydrogels with different suspension pH. X-ray diffraction and field-emission scanning electron microscope were used to characterize the structures of graphene oxide aerogels (GOAs), and electrochemical measurements were used to study the electrochemical performance of RGOAs. The results show that the structure of GOA is greatly affected by the suspension pH, and the GOA prepared at pH 3 has low restacking degree. The RGOAs obtained by steam reduction can retain the 3D structure well. The RGOAs reduced at 180 ℃ exhibits a high specific capacitance of 265 F g⁻¹ at a current density of 1 A g⁻¹, and excellent rate capability. This work suggests that steam reduction of freeze-dried GO hydrogels with a low degree of stacking is a feasible approach to prepare RGOAs as electrode material for supercapacitor application.

通过蒸汽还原具有不同悬浮液pH值的冻干氧化石墨烯水凝胶可得到还原的氧化石墨烯气凝胶（RGOAs）。用X射线衍射和场发射扫描电子显微镜表征了氧化石墨烯气凝胶（GOAs）的结构，并通过电化学测量研究了RGOAs的电化学性能。结果表明，悬浮液的pH值对GOA的结构有很大的影响，pH值为3时制备的GOA的重堆积度较低。通过蒸汽还原获得的RGOA可以很好地保留3D结构。在180℃下还原的RGOA在电流密度为1 A g ^-1时表现出265 F g ^-1的高比电容，以及出色的评分功能。这项工作表明，以较低的堆叠度对冻干的GO水凝胶进行蒸汽还原是制备RGOA作为电极材料用于超级电容器的一种可行方法。