Synthesis Of Photoelectrode Materials In Photoelectrochemical Cell And Their Photocatalytic Properties

With the development of social and economy,people are facing not only the depletion of fossil energy,but also the problem of fossil energy pollution to the environment.The development of new energy resources is one of the best ways to solve these problems.Hydrogen is one of the cleanest energy,as its high heat value,friendly environment,convenient transportation,and the product of combustion is water and harmless to the environment.The reserves of water and light are abundant on the earth and easy to obtain,so photoelectrochemical?PEC?water splitting to generate hydrogen over semiconductor photocatalysts have been considered as one of the most efficient,promising strategies to develop renewable energy for a sustainable society and a new option is provided to solve the global energy crisis and the greenhouse effect.In this paper,tungsten and copper-based oxide as main photocatalyst and no-noble metal oxide as co-catalyst were prepared.The structure and photoelectrochemical characterization of the composites were carried out.The photocatalytic activity and reaction mechanism of the composites were also investigated in semiconductor photocatalytic system and photoelectrochemical cell system.The main points were shown as follows:?1?A novel heterogeneous hybrid composed of consisting of nanolayered manganese-calcium oxide?MCO?and mesoporous tungsten trioxide?WO₃?has been fabricated by an ultrasonic,precipitation calcination method.The as-prepared samples were systematically characterized by XRD?FTIR,TEM,and XPS techniques,the results demonstrated that superior interfacial contacts had been formed between WO₃ and MCO.The DRS,IPCE and related photoelectrochemical measurements revealed an effective electron-hole separation.Photocatalytic activity test show that the photocatalytic hydrogen and oxygen production from the photochemical cell with optimized photocatalyst?MCO/WO₃-9?under 2 h simulated solar light irradiation was 1.9?mol and0.7?mol,respectively,at low extra bias of 0.90 V vs.RHE.?2?Mn₃O₄ nanoparticles decorated CuWO₄ composite was synthesized by spin-coating and deposition-annealing method.The morphology and structure of the nanocomposite were characterization by XRD,SEM,TEM,HRTEM etc which indicates the two types of materials come in intimate contact with each other.DRS,IPCE and photoelectrochemical measurements confirm a better light absorb effective and photoelectrochemical properties.As CuWO₄/Mn₃O₄-x composite acting as a photoanodic catalyst for overall water in a photoelectrochemical tandem cell.The optimal loading content of was Mn₃O₄ found to be 3%.Under 2 h sunlight simulator irradiation,ca.5.0?mol H₂ and ca.2.3?mol O₂ evolved,at extra bias of 1.20 V vs.RHE,respectively.?3?A heterogeneous photocatalyst composite composed of CuCr₂O₄ nanopartical and reduced graphene oxide?r-GO?was fabricated by a facile hydrothermal method.The composite photocatalystwas characterized by optical,morphology and photoelectrochemical measurements.As the optimal loading content of r-GO reach to 3%show the excellent photocatalytic activity.Upon 2 h UV-vis light irradiation,the amount of H₂ and O₂ was 4.98?mol and 2.38?mol at extra bias of 0 V vs.RHE respectively.And when CuCr₂O₄/r-GO-3 as photocathode and CuWO₄/Mn₃O₄-3 as photoanode H₂ and O₂ be collected from each electrode.