• 文献标题:   Microcrack Arrays in Dense Graphene Films for Fast-Ion-Diffusion Supercapacitors
  • 文献类型:   Article, Early Access
  • 作  者:   LI CM, LI XM, LIU GQ, YU W, YANG ZJ, WANG L, WANG C, YANG QZ, XIAO RL, HUANG F, TIAN HM, WANG CH, CHEN XL, SHAO JY
  • 作者关键词:   compact supercapacitor, fast ion diffusion, graphene, microcrack, roll to roll
  • 出版物名称:   SMALL
  • ISSN:   1613-6810 EI 1613-6829
  • 通讯作者地址:  
  • 被引频次:   0
  • DOI:   10.1002/smll.202301533 EA MAR 2023
  • 出版年:   2023

▎ 摘  要

Laminated graphene film has great potential in compact high-power capacitive energy storage owing to the high bulk density and opened architecture. However, the high-power capability is usually limited by tortuous cross-layer ion diffusion. Herein, microcrack arrays are fabricated in graphene films as fast ion diffusion channels, converting tortuous diffusion into straightforward diffusion while maintaining a high bulk density of 0.92 g cm(-3). Films with optimized microcrack arrays exhibit sixfold improved ion diffusion coefficient and high volumetric capacitance of 221 F cm(-3) (240 F g(-1)), representing a critical breakthrough in optimizing ion diffusion toward compact energy storage. This microcrack design is also efficient for signal filtering. Microcracked graphene-based supercapacitor with 30 mu g cm(-2) mass loading exhibits characteristic frequency up to 200 Hz with voltage window up to 4 V, showing high promise for compact, high-capacitance alternating current (AC) filtering. Moreover, a renewable energy system is conducted using microcrack-arrayed graphene supercapacitors as filter-capacitor and energy buffer, filtering and storing the 50 Hz AC electricity from a wind generator into the constant direct current, stably powering 74 LEDs, demonstrating enormous potential in practical applications. More importantly, this microcracking approach is roll-to-roll producible, which is cost-effective and highly promising for large-scale manufacture.