| In this dissertation, a multi-functional oligocarboxylic based chemical methods were developed to controlled synthesize inorganic micro- or nano- materials. With the assistance of various benign biocompatible agents such as citrate malate tartrate and gluconate, ZnO hierarchical nanostructures that assembled with distinct nanoplates were harvested. Theseα-hydroxy carboxylate played special role in the control of the aspect ration of ZnO nanocrystals and the formation of nanoplates. In addition, theα-hydroxy carboxylate based chemical route was also developed to the shaped controlled synthesis of silver nanoplates. Silver nanoplates with triangular sniped triangular or hexagonal frameworks were selectively obtained by selecting differentα-hydroxy carboxylate in the reaction. The main points are summarized as follows:1. A citrate assistance hydrothermal route was developed to the synthesis of ZnO micro- or nano- crystals. A hierarchical ZnO microparticles that assembled of regular arranged nanoplates were harvested. Experiments find that citrates can effectively prohibit the elongation of ZnO nanocrystals and formation of ZnO nanoplates. By carefully tuning the experiments factors such as the citrates concentration or reaction temperature, the shape of the ZnO nanocrystals could be alternated. Based on the shape evolution observations, two stages were suggested in the formation of the hierarchical ZnO microparticles: firstly formation hexagonal ZnO microplates, and the subsequent epitaxial growth of nanoplates on the (0001) surface planes of the ZnO microplates. The(0001) and (0001) show distinct activities in the second stage, resulting the formation of anisotropic microstructures. These phenomena were derived from the polar characteristics of ZnO crystals.2. A malate assistance hydrothermal route was developed to the synthesis of ZnO hexagonal microstructures. These hexagonal microstructures were composed of ZnO nanoplates that well arranged along the base planes. N2 adsorption/desorption curves showed there were small pores embedded in the ZnO microstructures. TEM and SEM observations confirmed the pores resulted from the interplaces of the nanolates. Similar to citrate, malates were effect in the control of the aspect ration of ZnO nanocrystales and the formation of ZnO nanoplates. The shape evolution investigations also found two stages involved in the growth: the formation of hexagonal ZnO seeds and subsequent epitaxial growth. The small pores formed in the second stage.3. Based on the principle "similar structures, similar functions", other multi-functionalα-hydroxy carboxylate such as tartrate and gluconate were applied in the shape controlled synthesis of ZnO nanostructures, and a series of hierarchical nanostructures based on ZnO nanoplates were harvested, indicating the importance ofα-hydroxy carboxylate in the aspect ratio control of ZnO nanocrystales.4. The room temperature PL of the ZnO powders prepared by theα-hydroxy carboxylate assistance routes was investigated. The samples showed intensive UV emissions, and the defects related emissions in the visible zone were greatly depressed. The improvement of optical quality of the samples were attribute to two factors: the chelating ability ofα-hydroxy carboxylate, and the surface adsorption. We also observed the red shift of UV peaks as the exciting power increased. In combination of the Raman spectrum we deduce this originated from the lasing-thermal effects during the investigation.5. Theα-hydroxy carboxylate assistance routes were also developed to the controlled synthesis of silver nanoplates with various frameworks such as triangular, sniped triangular or hexagonal shapes. Theα-hydroxy carboxylate were found to be crucial in the formation of silver nanoplates, and by selectively choosing theα-hydroxy carboxylate , the shape of the silver nanoplates can be alternated. The surface plasmon bands of silver ` can be turned to the near infrared zone.
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