Preparation And Performance Of High-performance Flexible Microsupercapacitors Based On Laser-induced Techniques

With the rapid development of the portable and wearable microelectronic products,the market demands for flexible energy storage devices are expanding gradually.As one kind of high-performance energy storage devices,supercapacitors（SCs）demonstrated the high power density and long cycle life,are attracting great attention for industry and scientific research.Among them,flexible microsupercapacitors（FMSCs）have been showing huge potentials in the field of scientific research and market demand owing to their foldable and lightweight properties.In this paper,a series of high-performance FMSCs were prepared by combining electrodeposition,papermaking technology and other technical methods on the basis of laser-induced graphene（LIG）electrodes.The main research works are as follows:（1）The FMSCs are fabricated through the layer-by-layer（LBL）electrodeposition of porous polyaniline（PANI）and the metal-organic frameworks（MOFs）crystals on LIG substrate.The conductive PANI chains are connected as a bridge to enhance the conductivity of the MOFs,and the MOF crystals are interspersed in the PANI chain layers to weaken the dense structure of PANI.Owing to the synergic effect of MOFs with highly porous structure and the PANI chains with the excellent conductivity,the resulting FMSCs exhibit improved capacitance performance with the largest areal specific capacitance of 719.2 m F·cm^-2at a current density of 0.5 m A·cm^-2,which is almost 370 times higher than that of FMSCs prepared by the bare LIG.（2）In order to break the limitations of traditional substrates in the field of FMSCs,we report a new method to prepare high-performance FMSCs via the combination of papermaking technique and laser-induced graphene technique.The papermaking technique allows the massive production of poly（p-phenylene benzobisoxazole）（PBO）paper,and the LIG process can directly convert the PBO paper into graphitized material.The resulting material exhibits excellent capability as electrode materials for FMSCs in terms of high power density,excellent cycle life,and good mechanical flexibility.The largest areal specific capacitance can reach as high as 44.4 m F·cm^-2and is 12 times higher compared to that of FMSCs prepared with the polyimide（PI）as a LIG substrate.Meanwhile,thanks to the unique hydrophobicity of the PBO paper,the LIG electrode prepared by the PBO paper can be used as an electrode substrate for electrodeposition,which provides the possibility to further improve the capacitance of the FMSCs.