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Three-dimensional (3D) interconnected porous nitrogen-doped carbon aerogels (CAs) have been successfully prepared with polyvinyl alcohol and nitrogen-containing N-phenylethanolamine as carbon and in-situ nitrogen sources, and boric acid as both crosslinking agent and 3D self-template. After drying, carbonization and KOH-activation treatment, the as-obtained CAs exhibit large specific surface area, hierarchically porous structure, heteroatom doping and superhydrophilicity. The optimal sample shows a high surface area up to 2016 m 2 g −1 with a total pore volume of 1.179 cm 3 g −1 . The synergistic effect of the reasonably hierarchical porosity, high effective surface area utilization, superhydrophilicity, and heteroatom pseudocapacitance are in favor of high specific capacitance of 467 F g −1 in three-electrode system and considerable cycle performance of 85.7%, 90.9% retention over 10,000 cycles at 20 A g −1 and 30 A g −1 . Moreover, the symmetric supercapacitor configuration delivers an energy density of 22.75 Wh kg −1 at power density of 262.5 W kg −1 and 7.6 Wh kg −1 at power density of 9572 W kg −1 . Here, we pioneer an in-situ self-template approach for fabricating hierarchically porous aerogels with a potential application in supplying a peak power for hybrid electric vehicles, memory backup systems, cold-starting assistants and especially electrochromic devices as demonstrated in our case. [ABSTRACT FROM AUTHOR]

• As-prepared carbon aerogels derived from PAAM-PANI xerogels with host-guest structures exhibits ultra-high BET surface area of 2805.07 m2 g−1. • Abundant functional groups form host-guest precursors can be well inherited, which exhibit high pseudo-capacitive performance. • The host-guest carbon aerogels have controllable specific surface area, adjustable pore size distribution and continuously interconnected porous structures and cross-linked mutual-supported networks. • The target carbon materials have displayed robust energy storage capability through EDLCs measurements, where the optimal sample shows 523 F g−1 at the current density of 1 A g−1. As a type of promising candidates for electric double-layer capacitors (EDLCs) electrodes, carbon aerogels should possess large surface area, hierarchical porous structures and abundant surface groups. However, ordinary carbon aerogels derived from their aerogel precursors with a single component will not have the possibility to fit some key requirements for energy storage as expected, one of which is mainly generated by the damage of the original structures of the aerogel precursors during preparation processes (like drying, calcining, etc). In this work, polyacrylamide and polyaniline as the two component precursors of host-guest structure carbon aerogels, and such in-suit combination strategy let as-prepared hybrid gels have continuously interconnected porous structures and cross-linked mutual-supported networks so as to form more stable skeleton for resisting the damage of their precursor original structures during preparation processes. After the carbonization and activation treatment, the resulted host-guest carbon areogel exhibits high BET surface area of 2805.07 m2 g−1 and huge pore volume of 1.46 cm3 g−1, which is almost the sum of the host-carbon aerogel with the single component of polyacrylamide and the guest-carbon aerogel with the single component of polyaniline. When they are assembled as electrodes in a symmetric capacitor device, the host-guest carbon aerogels present high specific capacitance of 523 F g−1 (1 A g−1) and long term charge-discharge stability over 10,000 cycles. Host-guest strategy will help to construct the carbon aerogel with controllable specific surface area, adjustable pore size distribution and continuously interconnected porous structures, cross-linked mutual-supported networks and abundant functional groups, which are most crucial factors to electrochemical performance of final carbon based EDLCs electrode materials. Image, graphical abstract [ABSTRACT FROM AUTHOR]