A facile route to prepare nitrogen-doped carbon microspheres/graphene aerogel with high compressibility and superior capacitive property

A facile strategy of spacer functionalization-lyophilization-annealing treatment is designed to synthesize nitrogen-doped carbon microspheres/graphene aerogel (N-CMS/GA) with three-dimensional (3D) hierarchical structure, high compressibility and excellent capacitive property. The as-synthesized PPy by weak oxidant (FeCl2/H2O2) owns high water wettability favorable for the self-assembly of the precursor into high-performance graphene-based aerogel. The N-CMS/GA exhibits a Young's modulus of 8.7 kPa, even compressed to epsilon = 90%, it could still rebound to nearly its initial volume. Besides, high specific capacitance (346 F g(-1)) at a current density of 1 A g(-1), superior rate capability (92 % of initial capacitance value kept at the current density increasing from 0.1 to 2.0 A g(-1)) and excellent cycle life (98.7% after cycling 10 000 times in 1.0 M KOH electrolyte) can be obtained. This research provides contributions to large scale and simple preparation of graphene-based hybrid aerogels for application in flexible devices whose mass and volume are limited seriously.