2D metal-organic framework Cu3(HHTP)2 composite electrode for flexible energy storage applications

Hydrothermally synthesized 2D metal-organic framework (MOF) Cu3(HHTP)2 was modified with carbon black (CB) and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT: PSS) to develop a flexible energy storage device. The efficiency of electron transfer and ionic diffusion within the pristine MOF was enhanced in the composites of MOFs. The MOF/CB/PEDOT: PSS (20 %) composite demonstrated more than 110 times higher capacitance compared with pristine MOF-based devices, reaching 336.93 mF cm-2 (146.51 F g -1 ) at 0.1 mA cm-2 . The developed device exhibited energy and power densities of 29.31 mu W h cm-2 (12.86 Wh.kg-1 ) and 39.38 mu W cm-2 (17.28 W kg-1 ), respectively. The addition of CB and PEDOT: PSS into the Cu3(HHTP)2 MOF decreased the pore structure due to the incorporation of solid materials in the pores and an excellent conductive channel for ion transfer. The study reveals that modifying the electrical, mechanical, and electrochemical properties of a 2D MOF can lead to the design of a highperformance flexible energy storage device for portable and wearable electronics.