Controllable Preparation Of Large-Area Flexible Low-Haze Conductive Film For Energy Storage Devices

Due to the wide application prospects in commercial electronic devices,medical testing,wearable electronic devices,etc.,flexible electronic devices have received continuous attention from researchers and made a series of breakthroughs.The transparency of flexible electronic devices has attracted extensive research interest in recent years.The transparent flexible supercapacitor is considered to be the key energy storage component for the development of wearable and fully transparent electronic devices.However,the development of current transparent supercapacitor electrode materials is in an awkward situation where good electrical conductivity and high energy storage capacity cannot be simultaneously achieved.And there are many challenges in the low-cost,large-area preparation of flexible transparent electrodes.In addition,the realization of high-definition for transparent energy storage electrode materials,especially transparent energy storage devices with visual applications and image functions,has been ignored by researchers.Herein,we developed a facile interfacial polymerization approach for the large-area preparation of flexible polypyrrole/polyethylene terephthalate(PPy/PET)transparent conductive films in a cost-effective way.PPy/PET film has a highly uniform surface morphology and good light transmittance.During the synthesis process,PPy/PET obtained different conductivity,light transmittance and haze performance by controlling the reaction time.Finally,a high-definition(2% haze level)PPy/PET transparent storage electrode film was obtained.Furthermore,by cyclic voltammetry,constant current charge and discharge and characterization of AC impedance,it is proved that PPy/PET materials have good tantalum energy storage behavior.It has great application potential in high performance energy storage.A facile strategy of etchant-written on the PPy/PET film is developed to fabricate the patterned micro-supercapacitors,which show a low haze level of 1.66% and a high transparency of 70.2%.Significantly,the low-haze micro-supercapacitor possesses high energy storage capacity and presents almost no capacitance loss at an extreme bending state.This work demonstrates a facile preparation of large-area and low-haze transparent flexible supercapacitors,and also enlightens broad interests in their potential integrity towards the fully transparent wearable electronics.Finally,PPy/PET films were used to prepare electrochromic-energy storage dual function devices and exhibited excellent electrochromic activity.Subsequently,we improved the storage capacity of PPy/PET and the stability of electrochromic cycle by means of a composite carbon nanotube grid structure.