Graphene-based Aerogels Derived from Biomass for Energy Storage and Environmental Remediation

To resist the energy crisis and increasingly environmental pollution, there is a great demand for the development of sustainable materials for use in high-performance energy storage devices and environmental applications. However, it is a great challenge to realize both ultrahigh power density and high energy density in symmetric supercapacitors (SCs) by using materials synthesized from bio-resources. Herein, we report the synthesis of hierarchical and lightweight graphene aerogels (GAs) with interconnected three-dimensional (3D) nanostructures for the fabrication of high performance coin cell-type SCs. GAs synthesized from pear exhibited high surface area (1001 m2 g-1) and pore volume (0.68 cm3 g-1), which tremendously increase its surface area up to 2323 m2 g-1, and pore volume of 1.15 cm3 g-1 after chemical activation. SCs based on activated GAs delivered both high energy density of 56.80 Wh kg-1 and high power density of 620.26 kW kg-1. The capacitance retention was ~83% after 10,000 successive cycles...