Hierarchically Divacancy Defect Building Dual‐Activated Porous Carbon Fibers for High‐Performance Energy‐Storage Devices

Renewable and environmentally friendly biomass‐based carbon electrode materials naturally possess fast ion transport, high adsorption, and excellent chemical stability for high‐performance energy‐storage devices. However, intelligently building the effectively biomass‐transferred carbon materials for the requirement of high energy density is still a big challenge to date. Here, a hierarchically divacancy defect building platform is reported for effectively biomass‐transferred and highly interconnected 3D dual‐activated porous carbon fibers (DACFs) based on the internal−external dual‐activation function of the pre‐embedded KOH and CO2 molecular. This uniquely interconnected frameworks not only fully provide the abundant active sites for ion interaction, but also efficiently guarantee the substantial accommodation for ion storage. Based on this, the as‐prepared DACFs‐based supercapacitors deliver a high energy density of 61.3 Wh kg−1 at a power density of 875 W kg−1 in the EMIMBF4 ionic liquid. This work not only provides a simple and efficient technique to enhance the energy density of carbon materials, but also probably promotes its additional application in environmental remediation. Renewable and environmentally friendly biomass‐based carbon materials has become a trend in the development of energy‐storage devices. A hierarchically divacancy defect building platform for effectively constructing biomass‐transferred and highly interconnected 3D dual‐activated porous carbon fibers not only fully provides the abundant active sites for ion interaction, but also efficiently guarantees substantial accommodation for ion storage.