| Recently, nanostructured composite system with nanoparticals and inorganic ororganic semiconductor functional materials attracted more and more attentions. And the emergency of nanomaterial increased the new connotations for the studies of nano-compound materials. Utilizing these nanoparticles with unique characteristics to synthesis in nanoscale can fully exert the buildup effects in each group. This gives a new way to develop high-performance new materials.The novel properties which semiconductor nanostructured composite system owned exhibit very broad application respect and all the properties correlate with its surface and interface characteristics. For the complexity and variety of properties in surface and interface, researching in this aspect will be a long course. On the other hand, what tool your using can get efficient and trusty information, respond to it's intrinsic rule in the studying course is very important too, This article involves two aspects discussed above.In this paper, using surface photovoltage spectroscopy (SPS) and field induced surface photovoltage spectroscopy (FISPS) as a dominated tool, we investigated the surface and interfacial electron structure, charge transfer character of two nanostructured composite system and the effect about atmosphere (water and oxygen) on the semiconductor nanoparticles. All the content involve three aspects as followed: 1. Studies of Photovoltage Property about Heterojunction Composite Film with 1,4-bis (Ferrocene) Thiophene and SnO2 NanoparticlesIn this paper, we successfully fabricated a novel heterojunction composite film composed of 1,4-bis(ferrocene)thiophene and SnO2 nanoparticles. The morphology andmicrostructure have been investigated by AFM and XRD. Their Optical and photovoltage properties were also studied using UV spectra and surface photovoltage spectra (SPS). The results indicate that the novel heterojunction composite film has higher and more wide photovoltage response in 300 ~ 550 nm regions than the singlefilm.2. Studies of Photoelectric Property about Nanocomposite Oxide With SnO2 and a -Fe2O3Using sol-gel method we prepared Nanocomposite Oxide with SnO2 and a -Fe2O3, We analyzed it's property With XRD UV spectra surface photo voltage spectra (SPS) and Field induced surface photovoltage spectra ( FISPS ). The XRD results confirmed that the nanocomposite oxide has two kinds of material with SnO2 and a -Fe2O3 ; The UV spectra has more variety with the proportion changing of the two kinds oxide; The FISPS indicated that photoelectric property increased with the adding positive electricity field , and the biggest strength could reach 50 ~ 60 times. With an increment for negative electricity field, the photoelectric property reduced largely. These results provide basal information and theories data for increasing the solar cell conversion, developing and exploiting the miniature photoelectron switching apparatus.3. Studies of photovoltage properties about semiconductor nanoparticles in atmosphere and ethanolWe have successfully synthesized a -Fe2O3 nanoparticles and a -Fe2O3/SnO2 nanocomposite oxide with Sol-gel method. With SPS and vacuum technology, we investigated the effect of adsorption (air and ethanol) on their photovoltage. As a result, we found that the photovoltage of both a -Fe2O3 and a -Fe2O3/SnO2 decreased greatly with the increase of vacuum. At atmosphere, both the materials can came back their original photovoltage intensity. But in ethanol, we couldn't get the same result. So we drew a conclusion that the external environments, such as water in atmosphere, oxygen etc, had great effect on the semiconductor nanoparticles surface electron structure and surface state, while ethanol has few effect on them.
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