Research On Self-assembly Technique Building Hollowcopper Sulfide And Their Catalytic Properties

In recent years,nanomaterials with a hollow structure have received extensive attention,due to their special structures and excellent properties.Among various kinds of nanomaterials with hollow structures,copper sulfide with a hollow structure is widely studied by researchers,because of its unique structure and application.A large specific surface area makes it possible for CuS hollow nanomaterials to have excellent catalytic properties,due to its special structural characteristics.In addition,CuS nanomaterials has been paid much attention,because the chemical composition itself is harmless to the humans' body and is friendly to the environment.At present,the methods for preparing the hollow structure are mainly divided into two major categories: the template method and the non-template method.Among them,the template method is widely used to prepare hollow nanomaterials.The template method has the advantages of its simple operation and the large amount of prepared production.However,it is difficult to completely remove the template when building the hollow structure with this method.Also,there will be some remains in the process of preparing,so the purity is relatively low.Although the non-template method can prepare such materials with a higher purity,the solvent used in this method is always toxic and the reaction conditions are a little severe.Therefore,the preparation process is harmful to the environment.In order to solve the two problems above,our study proposes a technology called the self-assembly technique.Green dissolution,such as ethanol were used to prepare morphology-controlled copper sulfide hollow nanoparticles.The work with details included the following two aspects:Firstly,the hollow nanostructures were constructed by self-assembly techniques using methacrylic acid anion?MAA-?,Cu²⁺ ions and thiourea with the help of desolvation.And then,the solvothermal method was used at low temperature.The constructed hollow structure was vulcanized to prepare the copper sulfide nanospheres with the hollow structure.Through the catalytic degradation of two cationic organic dyes,rhodamine B and methylene blue,the catalytic performance of CuS hollow nanospheres was examined.And the oxidation color reaction of 3,3',5,5'-tetramethylbenzidine as the substrate was also observed.The rate change verified the catalytic performance of the CuS hollow nanospheres.The results showed that CuS hollow nanospheres have a good catalytic performance and the fast catalytic rate to degradate the cationic organic dyes.The catalytic degradation reaction of Rhodamine B dye solution can be completed in 35 minutes.For the methylene blue dye solution,its catalytic degradation reaction can be completed within 70 minutes.Also,for the oxidation color reaction of TMB,the catalytic reaction yield was about 88.69%.Secondly,in order to further improve the catalytic performance of hollow structure CuS nanomaterials,the preparation method was changed and the preparation process was performed step-by-step.Firstly,Cu?MAA?2 microflowers with hollow structures were prepared by self-assembly technique using the ions of methacrylic anions?MAA-?and Cu²⁺ ions with the help of desolvation.And then,sulfur was added by the solvothermal method.Urea was used to vulcanize nanoflowers so that CuS hierarchical porous microspheres with the hollow structure were obtained.For this material,the same two types of catalytic systems were used to investigate its catalytic performance.The results showed that for two kinds of cationic organic dyes,the CuS hierarchical microflowers with the hollow structure showed more remarkable catalytic performance than the CuS nanospheres.In the meanwhile,the degradation of catalytic reaction to the dye was achieved mostly in the first 5 minutes.Rhodamine B could be largely degraded in 15 minutes,and completely degraded in 20 minutes.For methylene blue dye,the time of the reaction could be shortened to 20 minutes,which greatly improveed the catalytic efficiency.Also,in the oxidation color reaction of TMB,the reaction rate was also greatly increased,and the catalytic reaction yield was up to 94.50%.In addition,pure inorganic CuS particles were prepared by the laboratory preparation method and the application performance of the above two kinds of hollow nanomaterials were verified by comparative experiments.The results showed that the hollow-structured copper sulfide nano-materials was significantly better than ordinary inorganic copper sulfide particles.