Methyl Orange Degradation Under Visible Light Over The Heterojunction CuO/ZnO MPs Prepared With Precipitation Assisted Biosynthesis

Research on microstructures has become increasingly popular due to their peculiar physicochemical and catalytic features compared to bulk ones.The damaging effects of carbon-based contaminants particularly dyes have received important attention owing to its influence on human exists and the setting.Photocatalytic degradation of these color contaminants employing semiconductors has been proven as efficient means of eliminating these pollutants.Dissimilar semiconductors have been applied as a photocatalyst to remove these contaminants,amongst these materials;zinc oxide(ZnO)has attracted great attention because of its many superior properties.At room temperature ZnO a part from its wide band gap of 3.34 eV shows a large exciton binding energy of(60 meV)attractive for photocatalytic applications.ZnO due to its wide band hardly undergo degradation under visible light.However,doping with other metals or the formation of a heterojunction could improve its visible light application.Copper oxide(CuO),with a 1.2 eV narrow band gap and a variety of attractive physicochemical characteristic in several domains is reacted with ZnO to form a heterojunction through precipitation assisted biosynthesis method.However,previous works on producing heterojunction(CuO/ZnO)were limited to purely physical and chemical routes.Not only are these methods costly and require multiple reaction paths but they rely solely on the use of chemical substrates and environmentally unfriendly surfactants.Biological routes,on the other hand are classified as environmentally benign routes.Their limitations lie in their inability to effectively control the evolving morphology of nanomaterials.Compared to traditional chemical and physical methods or biological routes of fabricating CuO/ZnO MPs,a combined method founded on the use of plants extracts and some chemical methods have arisen as cost effective method to reach extremely steady and fewer toxic CuO/ZnO MPs at lower pH medium.In this thesis,we report the use of precipitation assisted by Cinnamomum Camphora(C.camphora)leaf extract to synthesize CuO/ZnO MPs.The prepared CuO/ZnO MPs are characterized based on morphology,structure and optical properties.And the as-produced heterojunction CuO/ZnO MPs are applied as visible light photocatalyst to degreed methyl orange(MO).The detailed structural,compositional,and optical characterization of the as-produced CuO/ZnO MPs are evaluated by TEM,XRD,FT-IR,EDX,PL and UV Vis spectroscopy.Distinct CuO/ZnO MPs manufactured by reacting 30 ml of aqueous Cu(NO3)2.3H2O and Zn(NO3)2.6H2O(0.1 M)with Cinnamomum camphora leaf extract(0.1 g/mL)at room temperature.Adjusting the pH of the mixture to 6 and annealed at 450 ? for 4 h.The BET surface area was found 15 m2/g.XRD analysis confirmed the purity and high crystalline nature of the CuO/ZnO MPs and EDX spectrum verified that pure CuO/ZnO was produced as it showed only peaks of Cu,Zn and O.Moreover,regulat:ing the synthesis limits such as the forerunner concentration,amount of leaf extract,and pH of the reaction solution affected the morphology of the as-formed CuO/ZnO MPs.The analytical application of CuO/ZnO MPs presented outstanding photocatalytic performance for the degradation of methyl orange(MO).A catalyst filling of 0.05 g of CuO/ZnO MPs could degrade MO of initial concentration of 50 mg/L under 50 minutes under visible light irradiation.The obtained results proved that the as-produced heterojunction CuO/ZnO MPs has potential applications as an efficient photocatalyst with excellent efficiency for the photocatalytic assisted degradation of organic pollutants in aqueous solution under visible-light irradiation.