Synthesis Of Several Core-shell Structure-inorganic Nanoparticles Coated With Conducting Polymer Composites And The Study Of Their Properties

In the process of micro-electronices sensors studies, looking for novel functional materials is an important aspect on improving sensitivity, extending applications and developing studies of sensors. The pure organic or inorganic materials can only provide single capability. However, inorganic/organic compound materials have accepted more attentions for their distinct excessive functionality. In recent years, with the rapid development of materials science, conducting polymers become hotspot materials as a new type of materials which have humidity properties. On the other hand, the structures of materials determine their properties. Preparation of special structure is the base of capability studies of materials. In this paper, we design and prepare inorganic nanoparticles/conducting polymer core-shell nanocomposites. The humidity-sensitive properties of the inorganic nanoparticles/conducting polymer core-shell nanocomposites were also studied.This paper is based on the preparation of functional materials with novel structures. We have mentioned a sort of experiment design model for the preparation of inorganic nanoparticles/conducting polymer with well core-shell structure. Then, we design and synthesis of several inorganic nanoparticles/conducting polymer composites. At the same time, the humidity-sensitive properties of the composites were also studied.Inorganic nanoparticles/conducting polymer composites design synthesis mechanism: In process of the preparation of inorganic nanoparticles/conducting polymer nanocomposites, the polymer monomers were added to the inorganic nanoparticles colloid and the polymer monomers are adsorbed onto the inorganic nanoparticles via hydrogen bonding or electrostatic interaction. After that, oxidant is added to induce the polymerization of polymer monomers and the polymer monomers are polymerized around the surface of the inorganic particles. Finally, inorganic nanoparticles/conducting polymer core-shell nanocomposites can be obtained. Furthermore, the size and morphology of inorganic nanoparticles would influence the core-shell structure of finally obtained composites.Firstly, we have design synthesis Ag/polyaniline and Ag/polypyrrole core-shell structure nanocomposites based on the Ag nanoparticles colloid for the first time. Through changing the reaction conditions such as reaction time and the ratio of reactant, we have discussed the factor influenced the reaction and determined the best reaction conditions finally. Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, UV-Vis spectra and conductivity test were used to characterize the obtained Ag/polyaniline and Ag/polypyrrole core-shell structure nanocomposites. Then, we prepared Ag/polyaniline core-shell structure nanocomposites films through in-situ oxidation polymerization method direct based on Ag nanoparticles colloid. Slide electrodes were used as the basic materials for preparation of the films. We have studied the humidity properties of Ag/polyaniline core-shell structure nanocomposites films with different Ag content. Humidity respond time of the composites films were decrease with the increase of Ag content in the composites. The sensitivity had no obvious changes. The resistances of the composites films were decrease with the increase of Ag content. The humidity property repetition of Ag/polyaniline composites films was well. For the humidity property of Ag/polyaniline composites films, we considered that its humidity respond mechanism belong to proton exchange mechanism and has two possible proton exchange processes. At the same time, we have prepared Ag/polypyrrole core-shell structure nanocomposites films and studied its humidity properties. However, the Ag/polypyrrole composites films have no respond to humidity.Secondly, octahedral PbS nanocrystals were synthesized in aqueous solution assisted with mixed cationic/anionic surfactants. Then we have design synthesis of PbS/polyaniline and PbS/polypyrrole core-shell structure nanocomposites based on the octahedral PbS nanocrystals for the first time. Electrostatic interaction between PbS nanocrystals and polymer plays a key role in the formation of the PbS/polymer composites. Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, UV-Vis spectra, Raman spectra and conductivity test were used to characterize the obtained octahedral PbS nanocrystals , PbS/polyaniline and PbS/polypyrrole core-shell structure nanocomposites. Then, we prepared PbS/polyaniline core-shell structure nanocomposites films through in-situ oxidation polymerization method direct based on octahedral PbS nanocrystals. Slide electrodes were used as the basic materials for preparation of the films. We have studied the humidity properties of PbS/polyaniline core-shell structure nanocomposites films with different PbS content. Humidity respond time and sensitivity of the composites films had no obvious changes with the change of PbS content in the composites. The resistances of the composites films were decrease with the increase of PbS content. The humidity property repetition of PbS/polyaniline composites films was well. For the humidity property of PbS/polyaniline composites films, we considered that its humidity respond mechanism belong to proton exchange mechanism and has two possible proton exchange processes. At the same time, we have prepared PbS/polypyrrole core-shell structure nanocomposites films and studied its humidity properties. However, the PbS/polypyrrole composites films have no respond to humidity.Finally, Octahedral Cu2O microcrystals were successfully prepared in aqueous solution using hydrazine as the reducing agent and assisted with mixed cationic/anionic surfactants. cetyltrimethylammonium bromide (CTAB) and dodecyl sulfonie acid sodium salt (SDSA) were used as the mixed cationic/anionic surfactants reaction system. In experiment process, through changing the reaction conditions such as temperature, time and the ratio of reactant, we have determined the best reaction conditions finally. We propose that the presence of the cationic/anionic mixture in the reaction system plays a key role in the formation of octahedral Cu2O microcrystals. The presence of CTAB will bring an increase in the growth rate of 100 faces, which favors the formation of octahedrons with eight 111 faces. The SDSA may play the assistant effect in the formation of octahedral Cu2O microcrystals.