| In recent years,wearable smart textiles with portability,wearability,and easy care have been developed rapidly,and their needs are increasing in various fields.For example,fabric electrodes can be woven into textiles for the collection of electrical signals in wearable smart clothing and also can be assembled into supercapacitor as a flexible energy storage component in wearable smart devices,providing continuous energy supply with small volume and good flexibility.The cotton fibers have the advantages of porosity,ight weight,softness,foldability and easy processing.Polypyrrole exhibits a combination of ease of preparation,good environmental stability,large theoretical specific capacitance,high biocompatibility,stretchable and soft.Metal organic framework has been widely studied in energy storage due to its porous structure,high specific surface area and sufficient number of redox active sites.Among them,Zr-MOF（UIO-66）itself has a certain pseudo capacitance,and the high-valence metal center Zr（IV）can enhance the strength of metal-organic crosslinking groups in water,ethanol and DMF.At the same time,it has excellent chemical stability under acidic conditions.In this thesis,combining the above advantages,UIO-66/Polypyrrole composite electrode materials were deposited on the cotton fabric as a flexible substrate,which can be used in flexible supercapacitors and wearable smart textiles.The main research contents are as follows:（1）The PPy@UIO-66@CT fabric composite electrode was successfully prepared by solvothermal method and introduction of"soft template"in-situ polymerization method on the fabric of UIO-66 and nano-tubular PPy.The conductivity of the PPy@UIO-66@CT fabric electrode was increased to 14.29S·cm-1.A specific capacitance of 565F·g-1(1993.44mF·cm-2)at a current density of 1.6mA·cm-2 was obtained for the PPy@UIO-66@CT fabric electrode.In addition,the proposed fabric electrode exhibited good cycling stability with capacitance retention of 95%after 500 charge-discharge cycles and excellent rate capability.The mass ratio specific capacitance of the PPy@CT fabric electrode prepared 301F·g-1 under the same conditions and After 500 cycles,only 46%of the capacitance remains.This is because the PPy nanotubes could serve as conductive connectors to bridge the UIO-66 particles due to their superior conductivity with one-dimensional structure.And UIO-66 not only provides its own tantalum capacitor,but also acts as a mechanical buffer.The capacitance is almost unchanged after 150 flexes and a peel test.This study confirmed the combination of MOFs and PPy nanotubes has great application prospect in fabric-based flexible supercapacitors.（2）The UIO-66 is deposited on the cotton woven fabric by solvothermal method,and the polypyrrole is loaded onto the cotton cloth by the freezing interface polymerization method.Successfully prepared PPY/UIO-66/Cwf fabric composite electrode.The electrode active material loading is commercially demanded and has a high electrical conductivity(18.89S·cm-1),and a large specific capacity of 3888mF·cm-2(410.4F·g-1)is achieved at a current density of1.6mA·cm-2.In addition,the capacity retention rate after the 1000 cycles was 73%.As a comparison,the specific area capacity of the PPy/Cwf fabric electrode prepared under the same conditions was 2724mF·cm-2,and the capacitance was few after 1000 cycles.This is because the freezing interface polymerization reacts under the condition of low temperature and multiphase to obtain more dense PPy,and the porous property of UIO-66 provides more growth active sites for PPy,due to the proper PPy loading at the polymerization time of 18h.The amount allows it to adapt to the powder expansion of PPy during the charge and discharge cycle.Therefore,we can think that the addition of UIO-66 improves the effective activity of the electrode material.At this time,the higher area capacitance is more prominent,Therefore it has a place in the energy storage of wearable textiles. |
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