Patterned Supercapacitors Based On Laser-induced Graphene

In the context of today’s era,the development of society is increasingly inseparable from electronic equipment,and therefore there is a greater demand for electrical energy.Although new energy industries such as wind energy,solar energy,and tidal energy have been developed for energy harvesting,due to time and space constraints,these energies cannot generate continuous and stable electrical energy for various devices.Therefore,explore how to prepare Efficient and stable energy storage devices are of great significance.Compared with traditional energy storage devices such as batteries,supercapacitors have the characteristics of high power density,fast charge and discharge capacity,and long cycle life,and have shown great application potential in various fields.The current shortcoming of supercapacitors is the low energy density.Therefore,how to improve the energy density of supercapacitors has become one of the focuses of research.Many studies have shown that electrode materials are the key factor determining the performance of supercapacitors.Among many materials,graphene is widely used in the field of supercapacitors due to its excellent physical and chemical properties.However,it still faces challenges such as complex preparation methods,high preparation costs,performance still needs to be improved,and low degree of patterning.In response to the above problems,we use iron-nickel layered hydroxide(Ni Fe-LDH),which with high specific capacitance properties,combine with laser-induced graphene(LIG)to fabricate a patterned,flexible,high-performance supercapacitors,and its application performance is demonstrated,the details are as follows:1.The LIG with interdigital electrode pattern is prepared on a polyimide(PI)film by a laser-induced method,which is simple in process and low in preparation cost.Then,the composite of electrode materials was efficiently completed by drop coating and drying,after that,the electrolyte was coated to assemble the patterned supercapacitor.The device performance was optimized from the perspective of equivalent series resistance,electrode pattern spacing,concentration of Ni Fe-LDH dispersion and other parameters.The morphology and composition of the composite electrode were characterized and analyzed by various testing methods.The porous structure of LIG and the high specific capacitance of Ni Fe-LDH jointly improve the performance of supercapacitors.At a scan speed of 10 m V/s,the area specific capacitance can reach8.45 m F/cm~2,which is 10 times that of the pure LIG case.In addition,the device can maintain the original performance under different bending angles,and the performance does not decrease significantly in the 400 times bending cycle test,showing excellent flexibility performance.2.We first test the actual power supply performance of Ni Fe-LDH@LIG supercapacitors,the supercapacitor banks constructed in series and parallel modes showed electrical performances in line with theoretical expectations.In order to demonstrate the practical application capability of the device,we built a flexible display system with STM32F103C8T6 as the main control chip and GDEW029I6F flexible display module as the main component,and successfully realized the switching and image switching functions using supercapacitor bank with three supercapacitors connected in series.In addition,since both the flexible display screen and the supercapacitor bank are based on PI,they can be integrated,and the integrated part can achieve repeated bending and multi-directional bending without affecting the system operation.In summary,the composite of Ni Fe-LDH material with high specific capacitance and LIG with loose and porous structure can prepare supercapacitors with excellent performance,then we use the supercapacitor group based on this supercapacitor to successfully light up the self-built flexible display.At the same time,an attempt was made to integrate the supercapacitor bank with the existing flexible circuit,which provided a new solution for the preparation of a fully flexible circuit system in the future.