【摘要】 构建了水热体系中AlOOH的结晶生长过程模型,首次从生长基元的角度研究了晶体结晶过程,深入原子层面揭示异形纳米AlOOH最终形貌形成的成因,从本质上解释水热环境pH值对结晶过程及最终形貌的影响机理,重点分析了不同pH条件下AlOOH的Al3+聚集体形态.根据[Al3(OH)4(OH2)9]5+及[Al3(OH)5(OH2)8]4+,[Al3(OH)6(OH2)7]3+等的配位特点,揭示了AlOOH定向生长为一维晶须和二维片状或三维颗粒的本质.用实验样品的形貌图像直接验证了所建模型的合理性,并用X射线衍射和红外光谱检测印证了不同pH条件下的聚集体形态及生长基元模型的正确性.更多还原

【Abstract】 The model of growth unit was established for synthesis of AlOOH in hydrothermal systems,and the transfer process of growth unit deduced.The crystallization process of substances was analyzed from the angle of motion of growth units for the first time.The influential mechanisms of different hydrothermal environment systems on crystallization process and final morphology of heteromorphic AlOOH particles were discovered from the perspective of atomic aggregates.Emphasis was focused on the mechanisms of growth unit at various pH values in acidic medium,and characteristics of Al3+ tripolymers,([Al3(OH)4(OH2)9]5+,[Al3(OH)5(OH2)8]4+ and [Al3(OH)6(OH2)7]3+) of nano-AlOOH.The formation process of the aggregates determined by various coordinate bonds of Al3+ tripolymers and the essence of oriented growth of AlOOH were discovered.The established model was directly proved with the experimental samples.Furthermore,the existence of polymers and motion of growth unit were proved right by means of detecting the infrared spectrogram.Various pH values determine different growth units,different growth units determines diverse successive transfer process,and finally determines one-dimensionally oriented growth of the crystal into different morphologies.更多还原