The Synthesis And Property Characterization Of The C12A7:e~- Electride

C12A7:e-has a unique crystal structure consisting of a positively charged framework having the chemical formula[Ca24Al28O64]4+,and four extra framework electrons,accommodated in the cages as the counter ions to neutralize the structure.Its unique structure and properties make it suitable for use in various fields,such as the electron injection layer,catalyst support and cathode material in a CCFL.Seeking for a new synthesis method for the large-scale preparation and research on its special properties has a great significance.In this thesis,we have successfully developed a series of techniques for preparing C12A7:e-and research its properties.This includes the following three parts:(1)synthesis the C12A7 powder with different methods and compare its properties;(2)a novel sintering process for high relative density and high electron concentration C12A7:e-ceramics;(3)the preparation of the C12A7:e-film and the adjustment of photoelectric properties.The major results and conclusions are listed below:The C12A7 nano-powders were prepared by solid-state reaction and hydrothermal synthesis respectively.The effects of synthesis conditions on the properties of the powders were investigated.The results show that:(1)the grain size of C12A7 powder obtained by hydrothermal synthesis at low temperature is the smallest(?35 nm),(2)the phase structure obtained by solid-state reaction is pure and the grain size distribution is uniform(73± 3 nm),which is suitable for the preparation of target.By direct heating the C12A7 powder in a carbon crucible,we get a high electron concentration target.The results show that the C12A7 phase does not decompose until heated to 1500 ?.The main component of the decomposition is C3A + CA.The electron concentration increase with the increase of the heating temperatures during 1250-1450 ?.And the optimum electron concentration(?2.3x1020 cm-3)can be obtained by heating at 1450 ? for 2 hours.We prepared the film by magnetron sputtering coating with the C12A7:e-target prepared above.The effect of different process parameters on the photoelectric properties of the films was investigated.The results show that the growth rate of the film is 1.5 nm/min at the RF power of 200 W,and the transmittance of the film can reach 90%even at the thickness of 690 nm and has a lower work function(?2.9 eV).The co-sputtering of C12A7 electron compounds with AZO can realize the adjustment of the photoelectric properties and work function(3.1 eV-4.1 eV)of AZO conductive films.The research results obtained in this thesis have some guiding significance for the preparation and industrial application of the low cost production of C12A7:e-ectride and its thin films.