Comparative study of LiMn{sub 2}O{sub 4} thin film cathode grown at high, medium and low temperatures by pulsed laser deposition

Journal Article · Fri Dec 15 04:00:00 EST 2006 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2006.08.025· OSTI ID:20900925

Tang, S B ^[1]; Lai, M O ^[1]; Lu, L ^[1]; Tripathy, S ^[2]

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1. Department of Mechanical Engineering, National University of Singapore, Singapore 117576 (Singapore)
2. Institute of Materials Research and Engineering, 3, Research Link, Singapore 117602 (Singapore)

LiMn{sub 2}O{sub 4} thin films with different crystallizations were respectively grown at high, medium and low temperatures by pulsed laser deposition (PLD). Structures, morphologies and electrochemical properties of these three types of thin films were comparatively studied. Films grown at high temperature ({>=}873 K) possessed flat and smooth surfaces and were highly crystallized with different textures and crystal sizes depending on the deposition pressure of oxygen. However, films deposited at low temperature (473 K) had rough surfaces with amorphous characteristics. At medium temperature (673 K), the film was found to consist mainly of nano-crystals less than 100 nm with relatively loose and rough surfaces, but very dense as observed from the cross-section. The film deposited at 873 K and 100 mTorr of oxygen showed an initial discharge capacity of 54.3 {mu}Ah/cm{sup 2} {mu}m and decayed at 0.28% per cycle, while the amorphous film had an initial discharge capacity of 20.2 {mu}Ah/cm{sup 2} {mu}m and a loss rate of 0.29% per cycle. Compared with the highly crystallized and the amorphous films, nano-crystalline film exhibited higher potential, more capacity and much better cycling stability. As high as 61 {mu}Ah/cm{sup 2} {mu}m of discharge capacity can be achieved with an average decaying rate of only 0.032% per cycle up to 500 cycles. The excellent performance of nano-crystalline film was correlated to its microstructures in the present study. - Graphical abstract: LiMn{sub 2}O{sub 4} thin films with different crystal size were grown at high, medium and low temperatures by PLD. Cyclic voltammograms of LiMn{sub 2}O{sub 4} thin film electrodes deposited at different temperatures show that the excellent performance of nano-crystalline film was correlated to its microstructures.

• OSTI ID: 20900925
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 12 Vol. 179; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CAPACITY
CATHODES
CRYSTALLIZATION
ELECTROCHEMISTRY
ENERGY BEAM DEPOSITION
LASER RADIATION
LITHIUM OXIDES
MANGANESE OXIDES
MICROSTRUCTURE
PULSED IRRADIATION
SURFACES
TEMPERATURE RANGE 0400-1000 K
TEMPERATURE RANGE 1000-4000 K
THIN FILMS