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.
2011, Vol. 11 
