Preparation Of Tungsten Oxide And Its Application In Functionalized Fibers

Tungsten oxide(WO3)is a low-cost,multi-functional semiconductor material with various properties such as electrochromism,photocatalysis,photochromism,gas-sensitive properties,and information storage.In recent years,due to nano-effects,the performance of nano-tungsten oxide materials have greatly improved and attracted more and more attention.In this paper,photochromic tungsten oxide with nanostructures was prepared by hydrothermal method.The preparation process,structure and photochromic properties of photochromic nanomaterials were studied.At the same time,photochromic fibers and fabrics were prepared by wet spinning process and coating method using the prepared photochromic materials.In addition,the one-dimensional structure of PVA/Tungsten oxide precursor nanofibers was also prepared by electrospinning.The tungsten oxide nanofibers were prepared by calcining,and the photocatalytic degradation of Rhodamine organics was investigated.The main research work is as follows:Sodium Tungstate Dihydrate was used as the tungsten source,Oxalic Acid was used as the auxiliary agent,Potassium Sulfate was used as the inducer,and Tungsten Oxide Nanosheets were synthesized.The size of the nanosheets was about 500 nm,and the color change occurred rapidly under UV irradiation.The color of tungsten oxide changes from yellow to blue within 1 min as UV light gradually deepens within 5 min,and the colored tungsten oxide will gradually return to its original state during the infrared heating process.It shows that the prepared photochromic tungsten oxide material possesses a reversible effect.The color began to become light within 5 minutes,and began to turn yellow after 30 minutes.After 2 hours,the sample can basically return to its original state.In the process of preparing the photochromic fiber,two methods are selected: one is to mix the PVA and the tungsten oxide uniformly by the wet spinning method to prepare the PVA/WO3 composite filament,and another method is to use the PVA/WO3 coating liquid to make a photochromic yarn.The prepared composite filaments or yarns all have a color changeunder the induction of ultraviolet light.The strength of the prepared composite filaments is generally low,easily broken,and the maximum strength is 16 c N.The prepared photochromic yarns had good photochromic reversible properties,and the reflectance spectrum was reduced from ~38% to ~19% under UV irradiation,backing to ~36% by Infrared heating treatment.The prepared photochromic yarn still has the ability of the photochromic after washed,and its mechanical strength can reach ~12N,which can be used to weave various interesting fabrics.In the experiments of preparing tungsten oxide nanofibers by electrospinning for the organic degradation of organic materials,tungsten oxide nanofibers prepared at 450°C can degrade 63% of Rhodamine under UV light at 72 W and 254 nm wavelength.In summary,the photochromic powder material prepared by the hydrothermal method has been successfully combined with the fiber or yarn to prepare an inorganic photochromic yarn with a photochromic function,and the application direction of the tungsten oxide has been expanded.At the same time,a reliable method for preparing a large number of photochromic fibers based on inorganic photochromic materials has been explored.The electrospinning has been successfully explored.Inorganic nanofibers were prepared,and their catalytic degradation of organic materials was studied.This has a certain guiding significance for the application of inorganic macromolecules made of nontoxic materials for the treatment of water pollution.