Surface Defect Modification Technology Of Graphene Based On ALD

Graphene has excellent optoelectronic and mechanical properties that can contribute to the future development of energy,industry,agriculture,and medicine.Graphene is soft and resistant to bending,and the transmittance of a single layer of graphene can reach over 95%.In addition,graphene has a mobility of up to 15,000cm²/V.s at room temperature,which has led to the increasing presence of graphene in cutting-edge research and the emergence of graphene-based composite devices in products.Energy storage devices based on graphene have also emerged in large numbers,taking advantage of its high specific surface area and high electrical conductivity,as well as its ease of doping modifications.To prepare graphene-based composites requires enhancing the surface adsorption capacity of graphene,because graphene itself is inert.However,graphene after modification can enhance the adsorption capacity of graphene,which also enhances the adsorption of functional groups,and it is based on this point that treats graphene modification by using UV/O₃.In this paper,because the adsorption ability of the defects and folds of graphene is a little stronger than other regions,and the purpose of our research is to use the defects of graphene itself for the growth of energy storage materials,and to prepare composite energy storage materials.But graphene itself has fewer defective spots and graphene has limited intrinsic adsorption capacity.Therefore,we chose to enhance the adsorption capacity of graphene by using UV and ozone treatments of different lengths of time.The experimental results show that the treated graphene has a stronger adsorption capacity than the untreated graphene,and it is found that the longer the UV and ozone treatment,the more easily the sp²hybridization of the carbon atoms in graphene is converted into sp³hybridization linkage.The longer the graphene is treated,the thicker the Zn O film grows on the surface of the graphene.We prepared a graphene/Zn O（20 nm）composite film through atomic layer deposition technique.We performed electrochemical tests on the prepared composite films by constant current charging and discharging and obtained a maximum surface capacitance value of 53.337m F/cm²at 4m A/cm².Finally,we assembled electrochromic devices using electrodes with the following structure:FTO/molybdenum oxide/electrolyte/graphene Zn O composite film/FTO.The device has a maximum optical modulation rate of 30%at 550 nm,and the device can be stable within 10 cycles,and it takes 91.2 seconds for coloring and 29.7 seconds for fading.