Versatile Strategy to Design Flexible Planar-Integrated Microsupercapacitors Based on Co₃O₄-Decorated Laser-Induced Graphene

Abstract

Flexible planar microsupercapacitors (MSCs) have become one of the most crucial energy storage devices for wearable and portable electronics on account of the superiorities of miniature size and easy integration with on-chip electronics. Under this background, we creatively design a versatile and facile strategy for in situ fabrication of flexible shape-controllable, planar microsupercapacitors based on Co 3 O 4 -decorated laserinduced graphene (LIG) on various substrates. This laser direct writing (LDW) patterning technique with advantages of simplicity, convenience, and low budget is applicable to customized polyimide films containing metal heterogeneous precursors coated on different flexible substrates to in situ generate metal oxide nanoparticles embedded in LIG patterning electrodes. These flexible designable-shaped, planar-integrated Co 3 O 4 /LIG MSCs exhibit excellent electrochemical performances, including high area-specific capacitances, excellent cycling stability, outstanding flexibility, and mechanical stability. Using this universal route, it can be proposed that flexible planar MSCs with desired shapes are fabricated on a variety of substrates for facilitating modular integration and biocompatibility to satisfy the requirements of microelectronics in the future.

Simple fabrication of Co3O4 nanoparticles on N-doped laser-induced graphene for high-performance supercapacitors

“…Therefore, efforts have been made to modify the LIG surface by heteroatom doping (N, S, B, and P), 16–18 functionalization, 19 and producing hybrid composites with pseudocapacitive materials. 20–22 For instance, heteroatom-doped LIG electrode material exhibited significantly improved capacitive performance compared with pristine LIG, as previously reported by our research group. 18 The integration of heteroatom-doped LIG with pseudocapacitive material is also a viable strategy to boost the electrochemical performance of SC electrode materials.…”

Recent trends in graphene supercapacitors: from large area to microsupercapacitors

“…By compositing these laser-processed graphene materials with pseudocapacitive elements, for example Co 3 O 4 (ref. 174) or Fe 3 O 4 (ref. 173), the energy density is being pushed towards the thin lm battery region, which are the best performing devices in terms of areal energy density nowadays.…”

“…An Fe 3 O 4 NP decorated LIG MSC achieved an outstanding capacitance of 719 mF cm À2 , and an energy density of 60.2 mW h cm À2 at 0.3 mW cm À2 power density, 173 while LIG with Co 3 O 4 achieved a much higher energy density of 286.38 mW h cm À2 at a similar power. 174 However, the achieved capacitance was much smaller, 1.9 mF cm À2 .…”

“…This electrode showed a high capacitance of 49 mF cm À2 and the symmetric MSC delivered a maximum energy density of 3.1 mW h cm À2 and a power density of 2.5 mW cm À2 . Following a similar approach but condensing the two laser irradiations into one, Liu et al 173 and Xu et al 174 pre-treated a polyimide lm with metallic precursors, which became metallic oxides at the same time as the polymer transformed into LIG. An Fe 3 O 4 NP decorated LIG MSC achieved an outstanding capacitance of 719 mF cm À2 , and an energy density of 60.2 mW h cm À2 at 0.3 mW cm À2 power density, 173 while LIG with Co 3 O 4 achieved a much higher energy density of 286.38 mW h cm À2 at a similar power.…”

Compared EC-AFM Analysis of Laser-Induced Graphene and Graphite Electrodes in Sulfuric Acid Electrolyte

“…The rapid growth of portable electronics, remote control systems, radio-frequency detectors, and micro-electro-mechanical systems has significantly increased the need for device miniaturization [ 18 , 19 , 20 ]. Currently, their potential is becoming more evident with respect to a fast charging–discharging rate, a long cycling life, flexibility, and shape diversity, together with their functional convenient size and their lightweight [ 21 , 22 ]. In addition, global climate change calls for the urgent development of carbon-neutral and renewable-energy rechargeable devices, such as batteries, and hybrid technologies, including electric vehicles [ 23 , 24 , 25 , 26 ].…”