Study On Flexible Electrode Material Of Attapulgite/Nano-Cellulose Composite Aerogel

In recent years,with the rapid development of science and technology,flexible electronic products that are portable,wearable,and easy to fold have entered people’s field of vision and caused a boom in people’s consumption.At the same time,research and development of energy storage devices compatible with these flexible electronics has become crucial.Common energy storage devices currently on the market,such as lithium batteries,solar cells,and ordinary capacitors,limit their development in the field of flexible electronics due to various factors.As a new type of energy storage device,supercapacitors have gradually become one of the main energy storage devices for powering flexible electronic products due to their advantages of small size,light weight,fast charging and discharging,long cycle life,and good stability.In order to meet the requirements of use,flexible supercapacitors first need to realize the flexible preparation of electrode materials during the assembly process.As a porous and lightweight three-dimensional flexible material,nanocellulose aerogel has become one of the candidate materials for flexible electrodes.However,when it is used as a flexible substrate,nanocellulose aerogel has some problems,such as poor stability and no electrochemical activity.In order to better solve the above problems,this subject chooses nanocellulose fibrils as raw materials,and attapulgite loaded with manganese dioxide as reinforcing and electroactive materials to prepare flexible electrode materials.On this basis,the stability and electrochemical performance of flexible electrode materials are further improved by in-situ polymerization of polyaniline.The results show that the flexible electrode material has a good application prospect in the field of flexible supercapacitors.The main results obtained are as follows:(1)Under the premise of retaining the original chemical and physical structure of CNF,the natural rigid attapulgite ATP is used as the reinforcement material,and the structural changes and performance differences of the composite aerogels at different mass ratios were explored.The experimental results show that when the mass of CNF and ATP is 2:1,the comprehensive performance of the prepared composite aerogel is outstanding.The composite aerogel at this ratio not only maintains the flexibility of the CNF aerogel itself to the greatest extent,but also shows better results in physical strength,thermal stability and moisture stability.In addition,the internal void structure of the composite aerogel prepared by liquid nitrogen pre-freezing is evenly distributed,and the longitudinally arranged straight-through tubular structure provides a good path for subsequent electrolyte and ion transport.(2)The preparation process of the electroactive material MnO2 nanoflowers was explored,and on this basis,the electroactive material MnO2 was loaded onto ATP by a one-step hydrothermal method.When the molar ratio of KMnO4 and MnSO4 was 3:1,birnessite-type MnO2 nanoflowers and ATP/MnO2 electroactive materials were successfully prepared after reaction at 160℃ for 15 h.The research results show that,compared with pure MnO2 nanoflowers,the MnO2 nanoflowers on the ATP/MnO2 electroactive material are more uniformly dispersed,smaller in volume,and larger in specific surface area can also provide more sites for charge exchange.When the current density is 0.5 A/g,the specific capacitance of ATP/MnO2 electroactive material can reach 138.2 F/g,which is 13.4%higher than that of pure MnO2 nanoflowers under the same conditions.(3)CNF-ATP/MnO2 flexible electrode materials were prepared using CNF and ATP/MnO2 electroactive materials.In order to further improve the performance of the electrode material,the in-situ polymerization of PANI was carried out on this basis,and the CNF-ATP/MnO2-PANI flexible electrode material was successfully prepared.The test results showed that with the introduction of PANI,the stability,strength and electrochemical performance of the original electrode material were improved.At a current density of 0.5 A/g,the specific capacitance of CNF-ATP/MnO2-PANI electrode material is 62.5 F/g,which is 61.25 F/g higher than that of CNF-ATP/MnO2 under the same conditions.At the same time,due to the redox property of PANI,the CNF-ATP/MnO2-PANI electrode material also exhibits pseudocapacitive characteristics on the electric double layer characteristics of the original electrode materials,forming a complementarity between the two.