Multi-functional PET Fabric Based On 3D Hierarchically Structured TiO₂ Nanowires

Combination of nanomaterials with textiles can prepare functional fabrics with high performance such as antibacterial,anti-static,anti-ultraviolet,smart wearable,self-cleaning propertites,which makes them an indispensable materials of the textile field.Because of its larger specific surface area and volume ratio,three-dimensional graded materials can effectively prevent nanomaterials from agglomerating,maintain the material's own structure without damage,and promote the coupling and synergy between materials,three-dimensional(3D)nano-building blocks have attracted wide attention from researchers.Construction of 3D nano-building blocks on fabric is very desirable in the field of high-performance fabric.On the other hand,TiO₂ material has the advantages of environmental protection,pollution-free,good stability,non-toxicity,etc.,and under the irradiation of a certain wavelength of light,it will generate photo-generated electrons and holes,which can further generate a certain amount of active hydroxyl radicals,degrading organic matter into CO₂ and H₂O.It is widely used in photocatalytic degradation,antibacterial,catalytic hydrogen production,air purification,sewage treatment,self-cleaning and other fields.In recent years,TiO₂ nanomaterials have been attempted in fabrication of various functional fabric composites.In this study,commercial polyester(PET)was used as the substrate,and the 3D hierarchical structure was organically combined with TiO₂ nanowires to prepare multifunctional textiles with photocatalytic degradation of organic pollutants,antibacterial and super-diphobic properties.Through the synergy of micro/nano effects,exploring the construction of functional 3D micro/nano structures with multi-scale levels provides new potential for improving the versatility of original textiles.The specific content is as follows:(1)Using Mg-Al LDH microchips as a template and Ti Cl₃ as the precursor of TiO₂,a low-temperature hydrothermal method was used to prepare a multifunctional polyester PET with3D hierarchical rutile TiO₂ nanowires(THNWP)coating in a supersaturated Na Cl solution.Fabric.By adjusting the concentration of the Na Cl solution,the amount of Ti Cl₃added and the template effect,the preparation mechanism of hierarchical TiO₂ nanowires was explored.The results showed that the concentration of Na Cl plays an important role in the crystal growth of TiO₂ nanowires.With the increase of Ti Cl₃ addition,the length of TiO₂ nanowires increases,and the denser the packing,the LDH template is very important for the growth of hierarchical structure.The supersaturated Na Cl solution,the addition amount of Ti Cl₃ and the template function are essential conditions for the construction of 3D hierarchical TiO₂ nanowires.(2)THNWP fabric with 3D hierarchical structure,the composite fabric exhibits good photocatalytic performance under ultraviolet radiation and sunlight.Under ultraviolet radiation,the composite fabric exhibits excellent antibacterial properties against both Escherichia coli and Staphylococcus aureus.The unique 3D hierarchical nanostructure constructed on the surface of the fabric,after further simple fluorination treatment,exhibits excellent super-biphobic properties.The experimental results showed that the contact angle of THNWP composite fabric to water is 169.1°,the rolling angle to water is 0.1°,n-hexadecane 156.2°/3.2°,n-tetradecane154.3°/5.1°,n-dodecane 152.7°/9.0°and n-decane 151.0°/14.0°.The air pockets trapped in the unique three-dimensional micro/nano structure of the composite fabric is an important factor for the fabric to have a higher contact angle.The theoretical calculation of the super-double phobic performance of the composite fabric is consistent with the experimental data.The higher surface roughness is more conducive to improving the non-wetting performance of the fabric.