Study On Preparation And Photocatalytic Properties Of Cu₂O With Different Morphologies And Its Nanocomposites

Cuprous oxide?Cu₂O?is a kind of p-type narrow band gap semiconductor material.The band gap is about 2.2eV.Because of its good absorption in the visible light,Cu₂O has been widely used in the field of photocatalysis,solar cell,gas sensing element and so on.Due to the high recombination rate of electron and hole generated by Cu₂O semiconductor in the light,the photocatalytic efficiency is low.Compared with the bulk materials,nanometer Cu₂O has better photocatalytic properties,but it is difficult to recycle and reuse because of its small particle size.In this paper,we mainly study the preparation of Cu₂O nanomaterials with different morphologies,TiO₂/Cu₂O,P25/Cu₂O and zeolite/Cu20 composite nanomaterials.Besides,we not only studied the influence of preparation conditions in the structure,morphology and photocatalytic properties of Cu₂O and its composite nanomaterials,but also explored the best conditions for the catalytic degradation of MO by zeolite/Cu₂O composite nanomaterials.The content of this paper mainly includes the following contents:1,Using a simple solvothermal method,the Cu₂O nanomaterials with irregular diamond,spherical,chamfer eight surface,and bundles morphologies were prepared.The photocatalytic degradation of methyl orange solution with different morphologies of Cu₂O nanomaterials under visible and no light conditions was analyzed.The experiment shown that at the low temperature and alkaline conditions and with glucose and hydrazine hydrate as reducing agent,Cu₂O with chamfer eight surface and irregular surface morphologies were obtained by reducing the Cu?NO₃?₂·3H₂O.The photocatalytic degradation efficiency of MO was 56.95%and 5.5%,respectively under visible light irradiation for 60 min.With glucose and hydrazine hydrate as surface active agent,the spherical and bundles Cu₂O were prepared under the condition of high temperature.The photocatalytic degradation efficiency of MO was 95.32%and 98.45%,respectively under visible light irradiation for 60 min.In the absence of light conditions,the four kinds of Cu₂O nano-materials with different morphologies all have good catalytic properties.The catalytic degradation efficiency of S1,S2,S3 and S4 were 75.75%,67.18%,95.32%and 98.45%,respectively.2,Anatase TiO₂ nanospheres were prepared by two step method,and the degradation performance of anatase TiO₂ nanospheres under UV light was compared with that of P25 TiO₂.TiO₂/Cu₂O and P25/Cu₂O composite nanomaterials were prepared by a simple hydrothermal method.The effect of TiO₂/Cu₂O molar ratio on the morphology and catalytic degradation of the composites was studied.Spherical titanium glycolate precursor was prepared at room tempreature,and the spherical TiO₂ was prepared by hydrothemal method at a certain temperature.Under UV irradiation for 60 min,the photocatalytic degradation of spherical TiO₂ and P25 were 94.72%and 99.46%,respectively.The spherical TiO₂ had the higher photocatalytic degradation than P25.P25/Cu₂O and TiO₂/Cu₂O nanocomposites were prepared by chemical reduction method using CuSO₄·5H₂O as the copper source and P25 and spherical TiO₂ as raw materials respectively.By changing the molar ratio of P25 and Cu₂O,the nucleation and growth happened on the surface of P25,which forming the small particles.When the molar ration is 1.0,the photocatalytic efficiency of composites reached the maximum which is 92.99%under visible light irradiation for 100 min.However,the photocatalytic degradation efficiency reduced with increasing the molar ratio.The catalytic efficiency of P25/Cu₂O composites reached the maximum at the molar ratio of 1.0 with no light irradiation,which was up to 87.98%.And the TiO₂/Cu₂O nanocomposites had the same variation law,the maximum photocatalytic efficiency was 92.99%at molar ratio of 1.0 under visible light irradiation for 100 min.The maximum catalytic of efficiency was up to 89.79%.Compared with P25/Cu₂O nanocomposites,TiO₂/Cu₂O nanocomposites had higher catalytic degradation efficiency and better recycling performance.3,Selecting methyl orange as the organic pollutants to analysis the photocatalytic degradation performance of zeolite/Cu₂O nano composite material in different concentration of MO and temperature.It is found that no photocatalytic activity exits for pretreated zeolite.Pure Cu₂O with chamfer eight suface structure own good photocatalystic activity which reached up to 55.95%under visible light irradiation for 60 min.The degradation effect of zeolite/Cu₂O nano composite material was the best,and the photocatalytic degradation efficiency was up to 89.55%at the same condition.With the increase of-the initial concentration of MO solution,the photo catalytic degradation efficiency of zeolite/Cu₂O nanocomposites increased firstly and then decreased.When the initial concentration of MO solution was 10 mg/L,the degradation efficiency was the highest?89.55%?.In addition,the the photocatalytic degradation performance of zeolite/Cu₂O nanocomposites increased with the increasing of reaction temperature at the initial stage of reaction and decreased in the later stage of the reaction.With the increase of temperature,the photocatalytic degradation of the composites firstly increased and then decreased.When the reaction temperature is 25?,the degradation efficiency is the highest?74.39%?.At the same time,the zeolite/Cu₂O nanocomposites has good recycling performance.The preparation methods used in the issue are relatively simple and easy to operate and control,which can prepared Cu₂O nanomaterials with different morphologies.And the production cost is greatly reduced.The prepared composite material in the light irradiation and no light irradiation all has better catalytic degradation to methyl orange,which own great potential application value.