Organic 3D interconnected graphene aerogel as cathode materials for high-performance aqueous zinc ion battery

Aqueous rechargeable zinc ion batteries are very attractive in large-scale storage applications, because they have high safety, low cost and good durability. Nonetheless, their advancements are hindered by a dearth of positive host materials（cathode） due to sluggish diffusion of Zn2+ in the solid inorganic frameworks. Here, we report a novel organic electrode material of poly 3,4,9,10-perylentetracarboxylic dianhydride（PPTCDA）/graphene aerogel（GA）. The 3D interconnected porous architecture synthesized through a simple solvothermal reaction, where the PPTCDA is homogenously embedded in the GA nanosheets.The self-assembly of PPTCDA/GA coin-type cell will not only significantly improve the durability and extend lifetime of the devices, but also reduce the electronic waste and economic cost. The self-assembled structure does not require the auxiliary electrode and conductive agent to prepare the electrode material, which is a simple method for preparing the coin-type cell and a foundation for the next large-scale production. The PPTCDA/GA delivers a high capacity of ≥200 m Ah g–1 with the voltage of 0.0～1.5 V. After 300 cycles, the capacity retention rate still close to 100%. The discussion on the mechanism of Zn2+ intercalation/deintercalation in the PPTCDA/GA electrode is explored by Fourier transform infrared spectrometer（FT-IR）, X-ray diffraction（XRD） and X-ray photoelectron spectroscopy（XPS） characterizations.The morphology and structure of PPTCDA/GA are examined by scanning electron microscopy（SEM） and transmission electron microscopy（TEM）.