Preparation Catalytic And Adsorption Properties Of Hollow Sphere CuS

Copper sulphide(CuS)is a P-type semiconductor material.The band gap is between 1.2 eV and 2.0 eV.It is widely used in superconducting,solar energy conversion,optical filters,catalysis and gas sensing due to unique physical,chemical and optoelectronic properties.The multi-stage geometry of copper sulfide has a higher specific surface area,better catalytic and optoelectronic properties than bulk CuS.Copper sulfide of hollow sphere,hollow tube,and rod have been prepared at present.However,The method of preparation need organic solvent,a high reaction temperature or a long reaction time,which is harmful for environmentally friendly,low energy and,mass production in practical applications.Based on the cognition of green chemistry.It is necessary and worthwhile to use a preparation method with low cost,simple and green reagent.In this paper,copper nitrate and thioacetamide(TAA)were used as copper sulfur sources respectively.Coprecipitation method was used to prepare copper sulfide with hollow sphere structure at low temperature.The crystal phase,structure,morphology and optical properties of the sample were characterized.Rhodamine B(20 mg/L)solution was used as simulated wastewater.The adsorption,photocatalytic properties and the relationship between them about the as-prepared were studied.The effects of copper sulfur source concentration,sulfur-copper molar ratio,reaction temperature,reaction time and pH value on the morphology,structure and catalytic adsorption properties of copper sulfide were investigated.The results show that:(1)CuS has been successfully synthesized.When the concentration of Cu(NO3)2 exceed 0.167 mol/L(CCu2+,0.167mol/L),CuS has a hollow sphere structure,and the outer diameter of the hollow sphere is 400-3500 nm,the shell thickness is 10-400 nm,When the molar ratio of sulfur to copper increases from 1 to 4,the outer diameter of the hollow sphere beccomes smaller,the shell becomes thinner,and the structure of the shell becomes loosened.When the molar ratio of sulfur to copper is 1(CCu2+= 0.33 mol/L),the obtained hollow sphere has a clear interface and a spherical shape.When the molar ratio of sulfur to copper is 4,the integrity of the obtained hollow sphere deteriorates.If CCu2+<0.167 mol/L,the morphology of CuS is flake or spherulitic.The formation mechanism of hollow spherical copper sulfide was affected by pH during the reaction.Because the hydrolysis of the sulfur source in the reaction system was acidic,TAA rapidly decomposed to form H2S gas,H2S as a sulfur source and soft template for nucleation growth of CuS.At the same time,the acidity of the solution playd a key role in the formation of hollow spheres.(2)As-samples have good catalytic and adsorption properties.The adsorption removal rate of RhB was 30%-87%,The photocatalytic efficiency was 50%-5%(The concentration of reaction solution was 20 mg/L.The reaction time was 120 min).When the adsorptivity was improved,the photocatalytic efficiency was lowered.When a small amount of H2O2 was added to the reaction system,the degradation efficiency was greatly improved.In this study,Three anionic dyes,cationic dyes and antibiotic wastewater were treated,When the concentration was 50 mg/L,reaction time was 40 min,the removal eff-iciency of RhB,malachite greenwas and tetracycline hydrochloride were 95%?94%and 90%.It can be seen that it has a good effect on the application of high concentration and high chroma wastewater.After 4 cycles,the sample still has 90%degradation eff-iciency,indicating that it has good stability.As-prepared sample of copper sulfide is a multifunctional material with good adsorption and catalytic performance.It exhibits unique treatment effect in high concentration and high chroma wastewater treatment.The pollutants is adsorbed,then it is degraded,which solved the problem that the catalytic material has poor treatment effect on high chroma wastewater and the regeneration of the adsorbent after treating the wastewater.It provides a better choice for the treatment of high concentration dye wastewater.At the same time,the green preparation method was easy to used in large scale,which lays a foundation for the practical application of catalytic materials.