Acta Phys. -Chim. Sin. ›› 2013, Vol. 29 ›› Issue (05): 911-919.doi: 10.3866/PKU.WHXB201302273


Phenomenon of Structural Transformation of Ethylenediamine- Oriented Synthesis of Microporous Cobalt Phosphate

LUO Qian-Qian, ZHOU Shi-Dong, REN Yuan, Li Niu, HUANG Zhi-Peng, GUAN Nai-Jia, XIANG Shou-He   

  1. Key Laboratory of Advanced Energy Materials Chemistry, Ministry of Education, Department of Materials Chemistry, Nankai University, Tianjin 300071, P. R. China
  • Received:2013-01-03 Revised:2013-02-27 Published:2013-04-24
  • Supported by:

    The project was supported by the Natural Science Foundation of Tianjin, China (12JCYBJC12700) and National Major Fundamental Research Program of China (973) (2009CB623502).


Microporous cobalt phosphate structures can be synthesized using ethylenediamine as a structure directing agent. During the syntheses of CoPO-en-1, CoPO-en-2, CoPO-en-3, and CoPO-en-4, it was found that they could interconvert during hydrothermal or calcination conditions. CoPO-en-2 and CoPO-en-4 are the crystallization intermediates of CoPO-en-1 and CoPO-en-3, respectively. During hydrothermal synthesis, CoPO-en-2 and CoPO-en-4 could be obtained at lower temperature or higher temperature during the initial crystallization stage. Extended synthesis time at higher temperature the two former structures transform into the two latter. CoPO-en-2, CoPO-en-3, and CoPO-en-4 could also convert to CoPO-en-1 during calcination, and these transformations indicated the sequence of structure stability. During synthesis under hydrothermal conditions, CoPO-en-2, CoPO-en-3, and CoPO-en-4 could convert to CoPO-en-1. During muffle furnace roasting, CoPO-en-2, CoPO-en-3, and CoPO-en-4 could also convert to CoPO-en-1. Different structures in the liquid or solid phases could be transformed into the same structure using different approaches.

Key words: Cobalt phosphate, Ethylenediamine, Structural transformation, Hydrothermal synthesis, Calcination transformation