Activated graphene nanosheets (AGNs) are fabricated from graphene nanosheets (GNSs) by the facile KOH activation process. It displays that the obtained AGNs have a hierarchical porous structure, leading to the superhigh specific surface area of 2662 m² g⁻¹. The obtained AGNs electrode exhibited high specific capacitance (238 F g⁻¹ at 1 A g⁻¹) and remarkable rate performance (79.41% at 10 A g⁻¹), exhibiting higher rate performance than reported carbon materials. Furthermore, the AGNs also show exceptional cycling capacity (99% after 20,000 cycles at 5 A g⁻¹) in 1.0 M TEA BF4/AN electrolyte with an ultra-high potential range from 0 to 3.5 V. The symmetric supercapacitor displays a high energy density of 42.78 Wh kg⁻¹ at a power density of 2071 W kg⁻¹ and excellent cycle stability. The superior electrochemical performance can be attributed to the high specific surface area that has a larger contact area with the electrolyte, and the porous structure which provides a richer ion transport channel.

活化石墨烯纳米片（AGNs）是通过便捷的KOH活化过程由石墨烯纳米片（GNS）制成的。结果显示，所获得的AGN具有分层的多孔结构，导致超高比表面积2662 m ²  g ^-1。将所得到的类星体电极表现出高的比电容（238 F G ^-1 1 A G ^-1）和显着的速率性能（在10甲克79.41％^-1），表现出速率的性能比报告的碳材料高。此外，AGN还显示出出色的循环能力（在5 A g ^-1的20,000次循环后，99％）在1.0M TEA BF4 / AN电解质中，其超高电位范围为0至3.5V。对称超级电容器在2071 W kg ^-1的功率密度下显示出42.78 Wh kg ^-1的高能量密度，并具有出色的循环稳定性。优异的电化学性能可归因于与电解质具有更大接触面积的高比表面积，以及提供更丰富的离子传输通道的多孔结构。