Plasma Induced Liquid Phase Synthesis Of Metal Nanomaterials And Their Photocatalytic Properties

Photocatalytic technology can realize the conversion of organic pollutants and plays a vital role in environmental governance.Photocatalyst is the soul of photocatalytic oxidation technology.Choosing a suitable photocatalyst is the key to achieve the catalytic degradation of pollutants.Ce/Mo metal oxides have been widely studied in the field of catalysis as redox catalysts.The interaction between different elements of Ce and Mo intensifies the generation of abundant defects(such as oxygen vacancy)in the conversion process between high and low state ions of elements,thus obtaining new materials with good light response ability.In this paper,Ce/Mo metal oxides were synthesized by hydrothermal method,co-precipitation method and plasma method in the mixed solvent of water/ethanol,respectively,and used for photocatalytic degradation of methyl orange wastewater.Different preparation methods determine the growth and formation of the material,and affect the light absorption capacity and photocatalytic effect of the material.The effects of different preparation methods on the photocatalytic performance of Ce/Mo metal oxides were discussed.Among them,the Ce/Mo metal oxide(P_o)prepared by plasma method showed better photocatalytic performance.In water/ethanol mixed solvent,the molar ratio of reactant Ce(NO₃)₃·6H₂O to(NH₄)₆Mo₇O₂₄·4H₂O was 3:1,the volume ratio of surfactant oleic acid(OA)to oleylamine(OAm)was 1:1,the discharge time was120 min,and the discharge voltage.The photocatalytic performance of Ce/Mo metal oxide synthesized under the condition of 7.12 kV was the best.Under ultraviolet light irradiation,0.5 g/L Ce/Mo metal oxide was used to degrade 1000 mL methyl orange(MO)solution with a concentration of 50 mg/L,and the degradation rate reached 98%in 18 minutes.The preparation of low-temperature plasma method can prepare more surface defect materials while shortening the preparation time of the material.The regular flower-like structure of Ce/Mo metal oxide greatly promotes the close contact between its flake and flake structure.The transfer between electrons led to a reduction in the probability of photo-excited electrons and holes recombination due to the small distance,which was the preparation of high catalytic activity effective preparation method of Ce/Mo metal oxide.Using plasma preparation method,using Ce(NO₃)₃·6H₂O?(NH₄)₆Mo₇O₂₄·4H₂O as the source of cerium and molybdenum,the surfactants cetyltrimethylammonium bromide(CTAB)and polyethylene glycol(PEG),in a water solvent Induce the synthesis of Ce/Mo metal oxide(P_w).Study the effect of preparation conditions such as the molar ratio of reactants,reactant concentration,discharge voltage,discharge time,mass ratio between metal oxides and surfactants,and mass ratio of surfactant CTAB/PEG on the photocatalytic performance of Ce/Mo metal oxides.The molar ratio of the reactant cerium nitrate and ammonium molybdate was 4:1,the mass ratio between the metal reactant and the surfactant was 1:0.41,the mass ratio of the surfactant CTAB/PEG was1.22:1,and the reactant concentration was 12 g/L,discharge The Ce/Mo metal oxide synthesized under the condition of 60 min and 6.20 kV discharge voltage showed better photocatalytic performance.Under ultraviolet light irradiation,using 0.8 g/L Ce/Mo metal oxide to degrade 1000 mL of 50 mg/L methyl orange solution,the degradation rate reached 98%in 12 minutes.In the photocatalysis process,the active radical hydroxyl radical(·OH),superoxide radical(·O₂^-)and holes(h⁺)are the main driving forces in the degradation of methyl orange solution.Ce/Mo metal oxide has excellent UV photocatalytic properties for organic dyes,and has potential application prospects in dye wastewater treatment.