Study On Preparation And Performance Of Potocatalytic Degradation Of Cuprous Oxide Powder And Film

Cuprous oxide (Cu2O) is a kind of important inorganic material, which is extensively used in the fields of coating, glass, porcelain, plastics, agriculture, and the industrial catalyst. Cu2O is a metal-oxide p-type semiconductor with a band gap of about 2.2eV, which has wide applications in solar cells, catalyst and gas sensors. In addition, Cu2O has attracted much current interest because of its superior photocatalytic properties in the field of pollution control.Cu2O powder was prepared by homogeneous reduction using CuSO4 and Na2SO3 (CuSO4:Na2SO3=1:1.2) in HAc-NaAc buffer solution. All the powders were characterized by X-rays diffraction (XRD), scan election microscopy (SEM) and Malvern Zetasizer Nano ZS laser particle size analyzer. The results show that all the microcrystals have even grain size and good dispersibility. The results of the orthogonal test show that there are three influencing factors on the granularity of Cu2O:reagent concentration, reaction time, temperature. The optimum conditions are 0.05mol/L,85℃,180min, the granularity of the powders obtained was 300nm. The photocatalytic of phenol in seawater with the as-prepared Cu2O powders under the visible light was investigated. The effects of chlorine ion on the photocatalytic activity of the Cu2O powders were investigated and discussed. The results show that the degradation efficiency of Cu2O decreased with the increase of the chlorine ion concentration. The efficiency in seawater is 23.3% in the condition of phenol initial concentration 80.0mg/L, radiation time 80min, amount of catalyst 2.0g/L. Under the same condition, the efficiency in solution can be 66.1%. The effects of catalyst amount and pH on the degradation of phenol are large.Cuprous oxide thin films have been prepared by chemical bath deposition method and liquid reduction approach on glass and copper surface, respectively. Effects of some technological factors for Cu2O thin films preparation and properties of the films have been investigated. Chemical bath deposition method is a simple preparation process, it has many advantages such as low cost, high purity, and can prepare large-size film used this method. With CuSO4 and Na2S2O3 mixed solution and NaOH solution as the reaction solution prepared Cu2O film on the glass surface. The results show that the chemical bath deposition method benefits the preparation of nano-Cu2O thin films with high quality and the optimal bath temperature is 60℃, control cyclic reaction times between 40 to 60, the optimum reaction solutions concentration are CuSO4 1.00mol/L, Na2S2O3 1.00mol/L, NaOH 1.00mol/L, in such conditions, high purity Cu2O films can be prepared. The photocatalytic activity of the as-prepared Cu2O film was evaluated by the photocatalytic degradation of methyl orange solution under visible light irradiation, methyl orange (10.0mg/L) has slight degradation with the participation of Cu2O film. We used a simple liquid reduction approach to prepare Cu2O film. At first, Cu(OH)2 film was prepared on the surface of pre-treated Cu foil with NaOH and (NH4)2S2O8 mixed solution; Cu(OH)2 as precursor and hydrazine hydrate or ascorbic acid as the reductant to prepare Cu2O film with different microstructure. With hydrazine hydrate as reducing agent prepared Cu2O film crystal is octahedral shape, crystal size is smaller; with ascorbic acid as reducing agent prepared Cu2O film crystal size larger, crystallization is not complete and apparent reunion grains. Reaction conditions have great influence on the Cu2O thin films, the reaction concentration:hydrazine should be controlled in 0.10～0.20mol/L, ascorbic acid should be controlled in 0.01～0.05 mol/L; the optimum temperature for hydrazine hydrate solution is 40℃, ascorbic acid is 60℃.