Glycine-nitrate combustion engineering of neodymium cobaltite nanocrystals  

作　　者：Ekaterina Alekseevna Tugova Oleg Nikolaevich Karpov 

机构地区：[1]New Inorganic Materials Laboratory,Ioffe Institute,Saint-Petersburg 194021.Russia [2]Department of Physical Chemistry,Saint Petersburg Electrotechnical University“LETT”,Saint-Petersburg 197376,Russia

出　　处：《Rare Metals》2021年第7期1778-1784,共7页稀有金属（英文版）

基　　金：the Russian Science Foundation(No.16-13-10252)。

摘　　要：NdCoO_(3)nanocrystals formed via glycine-nitrate combustion method followed by heat treatment has been systematically studied.Formation of NdCoO_(3)nanocrystals with minimal size of 7-10 nm from X-ray amorphous combustion products has been elucidated to be a very rapid process,occurring at the temperature of 550-600℃for5-30 min.The comparison of the minimum sizes of NdCoO_(3)crystallites obtained from the offered empirical relation dmin=lunit cell·N(where N is 7-12 and‘unit cellis elementary cell parameter)and the data determined on the basis of X-ray diffraction(XRD)and transmission electron microscopy(TEM)showed good correlation.The existence of special nanoporous microstructure and spatial limitations prevent NdCoO_(3)particle growth.The kinetic equation based on Avrami-Erofeev nucleation model was offered to be correlated well with experimental data of fractional conversion(a)versus isothermal time(s).The apparent activation energy(Ea=(338±32)kJ)of formation of NdCoO_(3)nanocrystals from X-ray amorphous combustion products obtained in excess of oxidant followed by heat treatment at 550-600℃was determined.

关 键 词：Rare earths PEROVSKITE Kinetics Mechanism Combustion synthesis NUCLEATION 

分 类 号：TQ038[化学工程]