Preparation Of Metal-Based Nano-materials And Their Research On Catalytic Degradation Of 4-Nitrophenol

P-nitrophenol(PNP)has high toxicity and good stability,which will cause serious harm to ecosystem due to their long-term existence.Over recent years,hydrogenation reduction method and advanced oxidation processes(AOPs)method have attracted intensive attention in the field of p-nitrophenol's treatment due to their high conversion efficiency,rapid degradation rate and eco-friendly advantages.4-NP removed by catalytic reduction process can be converted into organic substance p-aminophenol(4-AP)which has low-toxicity and can be degraded easily and used as an important chemical raw material.Therefore,the reduction method has appealing commercial value.The mechanism of advanced oxidation processed(AOPs)is to active oxidant to generate free radicals by an efficient catalyst,which can degrade 4-NP into harmless or low-toxic small molecular compounds.Exploring a low-cost,high-stability metal nanomaterial is of great significance to the development of two new technologies.In this paper,we improved the catalytic performance of catalysts by adjusting their morphology,the morphology and component composition of these catalysts were characterized by a variety of methods.This work can be divided into three parts as following:(1)We prepared PdFe alloy nanosheets with clear morphology by solvothermal method.The experimental results show that CO resolved from Fe(CO)₅plays a crucial role in the formation of the nanosheets.On the one hand,the CO can be used as a reducing agent to reduce Pd²⁺ions to Pd⁰atoms.On the other hand,CO can be uesd as a structure-directing agent to make the nanosheets grow laterally until forming PdFe alloy nanosheets.The electronic effect and synergistic effect between Pd and Fe are the main reasons why the catalyst has higher catalytic activity in the reduction of 4-NP system.(2)A novel carbon material particles(C-dots)were prepared by hydrothermal method,the particles'size was about 2.6 nm.Then PtRu/C-dots catalysts with different metal molar ratios were prepared by adjusting the amount of metal precursor solution.We can see that the bimetallic nanoparticles were wrapped by quantum dots and formed a chain shape through the TEM characterization.The synergistic effect between Pt and Ru alloy particles enhance the catalytic activity of catalyst,the high surface area of the carbon layer supports make the catalyst exhibit good stability.(3)We prepared highly uniform and well-dispersed Cu₂O nanomaterials with different morphologies by the one-pot method.The Cu₂O catalysts were used to activate peroxymonosulfate(PMS)to generate free radicals,which had high oxidizing ability to oxide 4-NP.The results show that the Cu₂O catalyst has good catalytic performance and stability.The influence of the experimental factors affecting degradation efficiency were discussed in detail,the experimental conditions for oxidative degradation of 4-NP in Cu₂O/PMS system were optimized.