Preparation And Adsorption Properties Of One-dimensional Cu-based Nanomaterials

In recent years,copper-based nanomaterials with one-dimensional linear structures have attracted extensive attention in adsorption applications due to their controllable size,diversified morphology,excellent physical-chemical properties.The emergence of these new adsorbents will provide new ideas for the treatment of dye wastewater.In this paper,one-dimensional Cu nanowires(NWs)were oxidized and sulfurized,and used to test the adsorption properties of Congo red(CR)and other dyes.The main work is as follows:(1)The oxidation and adsorption properties of Cu NWs were studied as follows:The first method was to anneal the Prepared Cu NWs in a tubular furnace under circulating air environment to obtain Cu@Cu₂O nanotubes(NTs);The second method is to oxidize Cu NWs in a hydrogen peroxide solution to form Cu@Cu O binary nanowires(Cu@Cu O NWs)modified with ultrathin Cu O ultrathin nanosheets(NSs).The adsorption test of Cu@Cu₂O NTs and Cu@Cu O NWs on CR solution with concentration of 100 mg/L showed that the final adsorption rates were 50%and 65%,respectively.(2)In order to improve the adsorption performance of Cu@Cu₂ONTs,it was combined with graphene oxide(GO)to successfully prepare Cu@Cu₂O@GO-NT-S ternary composite.The optimal ratio was explored by changing the GO compound amount.The experimental results showed that when the amount of GO was 20 mg,the maximum adsorption capacity of CR dye was 424.47 mg/g,which could be attributed to the fact that GO improved the dispersion of the material and increased the contact area with the dye.The adsorption of CR dye by Cu@Cu₂O@GO-NT-S conforms to the Langmuir isotherm and pseudo-second-order kinetic model,indicating that the adsorption behavior is dominated by the monolayer chemisorption.(3)In order to improve the adsorption capacity of Cu@Cu O NWs,the material was further vulcanized to obtain Cu₇S₄-NS-T composed of Cu₇S₄ NTs and Cu₇S₄ NSs.The formation of the hollow structure can be attributed to ion exchange and the Kirkendall effect.Cu₇S₄-NS-T is composed of both porous nanotubes and ultra-thin two-dimensional nanosheets.It shows remarkable adsorption capacity for CR and other anionic dyes,with a maximum adsorption capacity of 1166.07 mg/g.The adsorption behavior accords with the Langmuir isotherm and the pseudo-second-order kinetic model,which proves that chemisorption is the main control process of anionic dye enrichment.