| With the advance of science and technology,new energy materials have become a hot spot of technical research.Among them,photolytic aquatic hydrogen using semiconductor nanomaterials to realize the conversion of chemical energy to electric energy is emerging one after another.However,there are still many problems in semiconductor photoelectric materials,such as low conversion efficiency,poor light corrosion and weak stability,which seriously restrict the development of the field.Because of the abundant earth reserves,low price and non-toxic advantages,metal oxide has become the first choice of photoelectric catalytic materials.However,the selection of catalytic materials must balance catalytic activity,stability and practicality,so finding suitable metal oxide materials remains a huge challenge.In this paper,typical metal copper oxide was taken as the research object,and the microstructure and photoelectrical properties of semiconductor materials such as CuO nanosheet,Cu2O/TiO2 nanoarray core-shell structure,and CuO/Cu2O heterostructure were studied in detail.A series of tests and characterization were conducted to optimize the stability under the premise of ensuring its catalytic activity.The research contents are as follows:(1)Cu(OH)2 nanoplates were successfully synthesized by thermal evaporation.After calcining at high temperature in different atmospheres,CuO nanometer flakes with a single thickness of 100?500 nm were formed.Electrochemical tests were conducted on the prepared samples,and the photocurrent was negative,indicating that the obtained samples were p-type.It was found that the sample treated in air had the maximum photocurrent(?120?A)and highest carrier concentration(2.9 x 1021 cm-3).Through the analysis of XPS and UPS measurement data,it was found that H2/H2O could occur in the samples annealed in the air due to the increase of carrier concentration and the shift of Fermi energy level.Meanwhile,its electrochemical specific surface area was larger,resulting in the easier PEC reaction.(2)The core shell Cu2O/TiO2 nanorods was synthesized by two-step method.TiO2 nanorods was firstly prepared by hydrothermal reaction route and then anodized in NaOH solution and supported by electrodeposition with n-type Cu2O nanoparticles with diameters of-20 nm.The photocurrent of the samples was measured in Na2SO4 and H2O electrolytes,and it was found that the photocurrent of T-N-Cu sample electrodeposited after NaOH anodic oxidation reached?118 A(0 V vs Ag/AgCl).The performance improvement was attributed to the increase in specific surface area after anodic oxidation and the construction of TiO2/Cu2O ? semiconductor heterojunction.(3)P-CuO nanoplates were prepared by hydrothermal method,then,by introducing the ethanol solution,30nm n-Cu2O nanoparticles were grown on p-CuO nanoplates to form p-n junction.It is found that the p-n formed by CuO and Cu2O is a type ?-semiconductor heterojunction,which increases the separation of photogenic carriers under illumination,and the depletion layer formed prolongs the carrier life,so it has a high photocurrent.The PEC test results showed that the photocurrent of the n-Cu2O/CuO heterostructure was increased twice as much as that of the pure phase CuO,and the highest photocurrent density was 150 ?A.The paper is based on the synthesis of copper oxide and its photoelectric chemical properties test research,it is of referential significance to the application of oxide semiconductor materials in photohydrolysis. |
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