Surface Photovoltage Studies Of ZnO Nanoparticles And Their Heterostructures

Zinc oxide(Zn O), with its excellent photoelectric properties, have been attracting people’ wide interest in the growth of Zn O mechanism, morphology control and luminescence mechanism. With the decrease of the Zn O size, the research range from macro-regional to micro nano area. People have used their property and created many photoelectric devices such as solar cells, LEDs and sensor etc. Cd Se nanocrystals and organic polymer have potential application prospect in solar energy conversion, lighting,display technology and biological application. In the same condition, the composite structure materials of Zn O, Cd Se, and organic polymer have more superior optical performance and electronic transmission capacity than single materials, so it is necessary for us to understand the surface and interface photoelectric properties of Zn O nanoparticles and its composite structure,which has important significance to design new nano optoelectronic devices. In this article, we use the surface photovoltaic technology- Kelvin probe to study the photovoltaic properties of Zn O nanoparticles and its composite structure.The main contents are as follows:1、 Using sol-gel method and zinc acetate, tetramethyl ammonium hydroxide and dimethyl sulfoxide as main raw materials to make Zn O nanoparticles. The obtained Zn O was characterized with transmission electron microscopy, X-ray diffraction spectra andphotoluminescence spectra, which indicated that Zn O nanoparticles are wurtzite structure with a heterogeneous particle size.Photoluminescence spectra showed the visible luminescence properties, which indicated that the Zn O nanoparticles have many defect state. Based on the Kelvin probe photovoltaic technology to explore the surface photovoltaic properties of Zn O nanoparticles under different experimental conditions.2、 Using high temperature liquid phase heat injection method to prepared Cd Se quantum dots. The obtained Cd Se were characterized with transmission electron microscopy(TEM), fluorescent UV absorption, which showed that the Cd Se quantum dots have uniform particle size. The particle size increases with the increase of reaction time and the absorption peaks redshift. We prepared Zn O/Cd Se composite structure and uesd the Kelvin probe photovoltaic technology to study thesurface photovoltaic properties of heterostructure.3、 Using the Zn O nanoparticles and P3AT(ploy-3dodecylthiophene) to make composite heterostructure through spin-coating. Kelvin probe was used to study surface photovoltaic properties of heterostructure. It was found that that heterostructure interface state increased with the increase of concentration by changing the concentration of P3 AT and that the SPV starting peak position changes with temperature changes by changing annealing temperature within the scope of the P3 AT photon-absorption.