Synthesis Of Copper-based Nanomaterials And Their Adsorption And Photocatalytic Properities

In recent years,with the decrease of the fresh water on which human beings live,so the research of treating dye wastewater is of great practical significance.Inorganic nanomaterials have always attracted much attention in which copper-based materials are potential materials could applicate on adsorption and photocatalysis for the removal of dyes pollutions and performed well.Its main contents are as follows:(1)A series of cuprous oxide(Cu2O)and sulfur-incorporated cuprous oxide(S-Cu2O)nanomaterials were synthesized by a facile chemical reduction method,in which CuCl2·2H2O and thioacetamide(TAA)were selected as copper and sulfur precursors,respectively.S-Cu2O particles with different doping amount of sulfur were prepared by changing molar ratio of TAA to CuCl2·2H2O.Sulfur incorporation favors the formation of small sized S-Cu2O particles compared with Cu2O.(2)Adsorption behaviors of Cu2O and S-Cu2O nanomaterials were evaluated on adsorption of MO from aqueous solution.The adsorption capacities of the liquor were determined under UV-vis spectrophotometer(TU-1901,Beijing,China).Sulfur incorporation is provided for enhancing adsorption performance for the removal of MO on S-Cu2O and the superior adsorption capacity of 954.69 mg·g-1 is achieved on the S15%-Cu2O adsorbent.Adsorption reactions of the S15%-Cu2O adsorbent for MO were well described by pseudo-second-order kinetic model and Langmuir isotherm.The maximum adsorption capacity was 1485.24 mg·g-1.The value of free energy(E,KJ·mol-1)calculated from D-R model indicated the adsorption process was physical adsorption.Adsorption thermodynamic proved the adsorption process was exothermic and spontaneous.Anionic dyes could be adsorbed selectively on the S15%-Cu2O adsorbent and separated from cationic dyes.The adsorption mechanism could involve electrostatic attractions and n-?interactions of S-Cu2O and MO.Density functional theory calculations showed a pronounced electron accumulation on the sulfur sites,benefiting to the adsorption on S-Cu2O.Since these accumulated electrons strengthened the n-? interactions between the sulfur and MO.(3)Copper sulfide(CuxS)nanoparticles were synthesized through chemical precipitation,the effect of copper source,temperature,reaction time and the ratio of copper to TAA were adjusted to get Cu7S4 with high crystallinity.Cu7S4/CdS nanocomposite materials were prepared by hydrothermal reaction and photocatalytic activities were evaluated.The H2 generation rate is 6.16 mmol·g-1·h-1,and the degradation rate reached 92.1%for methyl blue(MB).