Abstract
Kinetics and formation mechanism of undoped and Al-doped LiNiO2 from Li2CO3 and NiO were investigated in this study. Without the addition of Al ions, sluggish kinetics for the formation of undoped LiNiO2 was observed. The fraction of undoped LiNiO2 reached 50% after Li2CO3 and NiO reacted at 700°C for 150 min. With the addition of 25% of Al ion, the fraction of Al-doped LiNiO2 reached 50% within 60min at 700°C. The analysis of kinetics study indicates that the formation of undoped and Al-doped LiNiO2 is a diffusion-controlled process. Furthermore, the rate constant determined from Jander model {[1 - (1 - α)1/3]2 = Kt} was significantly enhanced by the addition of Al. The activation energy for the formation of LiNiO2 drastically decreased from 190k J/mole (undoped reaction) to 83 kJ/mole when 25% Al was added. The enhancement of LiNiO2 formation by Al doping is attributed to the structure resemblance between α-LiAlO2 and LiNiO2. α-LiAlO2 acts as the seeding material which provides nucleation sites for the growth of LiNiO2.
Original language | English |
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Pages (from-to) | 97-106 |
Number of pages | 10 |
Journal | Journal of Solid State Chemistry |
Volume | 167 |
Issue number | 1 |
DOIs | |
Publication status | Published - 2002 Aug |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry