Preparation And Properties Nanocopper/Graphic Carbon Nitride Functional Fibers

In recent years,with the continuous improvement of people’s living standards,the requirements for the indoor environment have also been continuously improved.The problem of indoor second-hand smoke pollution has always attracted people’s attention.Indoor second-hand smoke not only causes harm to the indoor environment,but also brings a series of physical health problems.The new crown pneumonia epidemic that broke out in the winter of 2019 has not yet completely eliminated the hazards,and the demand for antibacterial and antiviral materials for indoor degradation of pollutants has increased.Semiconductor photocatalysis technology has always been regarded as one of the most promising pollutant treatment technologies,which can effectively eliminate some organic pollutants at low cost.Inorganic nano-metal materials have been widely used in various applications such as indoor air purification because of their excellent antibacterial properties.However,most of the photocatalysts exist in the form of powder,which is easy to agglomerate and deposit or dissipate when in use,which is not convenient for recycling and reuse.Therefore,it is necessary to load the catalyst powder on a suitable carrier to solve the problem of dispersion and recovery.Compared with inorganic carriers,organic materials are more suitable due to their superior flexibility and ease of processing.In recent years,the two-dimensional layered material graphite phase carbon nitride（g-C₃N₄）has been widely used for photocatalytic degradation of pollutants in water and air due to its low cost,non-toxicity,stable chemical properties and visible light response.However,pure carbon nitride materials still have problems such as weak visible light absorption and low photo-generated carrier separation efficiency.In order to improve the photocatalytic efficiency and solve the problem of catalyst dispersion,this paper uses nanocopper to modify g-C₃N₄,and fibers were used as the carriers.The catalyst was loaded on the fiber to prepare a multifunctional photocatalytic composite fiber material.The composite material not only had effectively photocatalytic activities,but also had excellent antibacterial properties.In the second chapter,the nanocopper particles were firstly deposited on the surface of g-C₃N₄ by in-situ reduction method.The reduction method using L-ascorbic acid could effectively protect the Cu particles on the surface from oxidation.Then the low melting point sheath-core polyester fiber（LMPET）was chosen as the carrier,and Cu-g-C₃N₄ composite was loaded on the surface of LMPET through the padding-baking method to prepare Cu-g-C₃N₄@LMPET.Characterization results such as field emission scanning electron microscopy and Fourier infrared spectroscopy all proved that Cu-g-C₃N₄ were successfully loaded on LMPET.Cu-g-C₃N₄@LMPET exhibited excellent photocatalytic degradation performance and excellent cycle stability to organic pollutants nicotine under the irradiation;Cu-g-C₃N₄@LMPET also had high antibacterial activity to both S.aureus and E.coli.In the third chapter,in order to further improve the catalytic performance of photocatalytic materials in water environments and solve the problem of poor hydrophilicity of polyester fiber carrier materials,cotton fibers with better hydrophilicity and environmental friendliness were selected as the carrier.At the same time,in order to make g-C₃N₄ more firmly supported on the carrier and the loading method more universal,g-C₃N₄ was modified to obtain g-C₃N₄-CONH-KH550 by introducing silance coupling agent.g-C₃N₄-CONH-KH550 was bonded to the cotton fiber surface,and then the Cu particles were reduced on the surface by adding L-ascorbic acid using the in-situ reduction method to prepare Cu@g-C₃N₄-cotton.The tensile performance test showed that Cu@g-C₃N₄-cotton still maintained strong mechanical properties and could meet the requirements for regular use.Photocatalytic experiments showed that Cu@g-C₃N₄-cotton had excellent photocatalytic degradation ability and cycle stability for organic pollutants nicotine.Antibacterial experiments showed that Cu@g-C₃N₄-cotton had excellent antibacterial ability of E.coli and S.aureus.The bacteriostatic reduction rates reached over 99.5%.The degradation products and process of the substrate were explored by UPLC Synapt G2-S HDMS.This paper provides a new idea for constructing a highly efficient and stable multifunctional photocatalytic composite fiber material,which is expected to be applied in the field of environmental purification.