JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2024
·Vol. 110
·期 3
·678-689
·
IF 2.3
Hou Ruiting,Wang Shaozheng,Wang Haishan,Tian Lanlan,Zhu Xiangxiang,Li Yule,Chen Qingming,Zhang Hui
La 1- x Ca x MnO 3 , as a candidate for thermal radiation detectors, has received more attention due to the quest for a higher temperature coefficient of resistance (TCR), however, the narrow high-TCR temperature range greatly limits its application in uncooled bolometer. In this paper, Mn 3 O 4 - La 1- x Ca x MnO 3 ( x = 0–0.33) composite ceramics were prepared using the sol-gel method. A suitable TCR was achieved over a wide temperature range, including room temperature, by adjusting the Ca content. As the Ca content decreased, the resistivity ( ρ ) of the composite gradually increased at 300 K, and the positive TCR (PTC) peak shifted to a lower temperature. However, the negative TCR (NTC) was enhanced over a wider temperature range. When x = 0.05, the maximal NTC was −3.2%·K −1 within the range of 172 K–350 K and |TCR| > 2%·K −1 , spanning a large temperature range around 180 K, including room temperature. These results strongly indicate that the composite, such as Mn 3 O 4 - La 1- x Ca x MnO 3 , provides a new idea for uncooled bolometer/night vision. Graphical Abstract
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Zihao Chen,Jiamei Han,Xin Gu,Kaikai Wu,Jiabin Jiang,Liming Zhao,Yixin Yan,Haitao Wang,Xiaolu Liang,Yao Wang,Zhenyu Wang,Xiaokun Zhu,Zimeng Pan,Xiang Liu
Perovskite manganese oxides are highly desirable for infrared acquisition owing to their characteristics of ferromagnetic metal-paramagnetic insulators. In this work, the sol-gel spin-coating technique was employed to prepare La 1- x Ca x MnO 3 (LCMO) films with varying Ca 2+ content ( x = 0.1, 0.2, 0.3, 0.4, 0.5) on the (l00) LaAlO 3 (LAO) substrates. In comparison to previous studies, the pre-sintering temperature, final sintering temperature, and final sintering period were modified. The crystal structure, surface topography, elemental valence states, and electrical transport performance of the LCMO films were characterized and analyzed as well. The results demonstrated that the diffraction peaks of the above films were aligned with those of the LAO single-crystal substrate. The change in Ca 2+ content caused an increase in the Mn–O bond length, the amount of Mn 4+ , and the Mn– O –Mn angle in LCMO films, promoting the double exchange effect. These modifications had a considerable impact on the resistivity of LCMO films, increasing their TCR value. The maximum TCR of 22.92% K −1 was reached at x = 0.3 and peak TCR temperature ( T k ) of 241.93 K. Therefore, the film has great application potential for infrared bolometers.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Xiaohan Yu,Shuaizhao Jin,Xiaoli Guan,Yixin Yan,Kaikai Wu,Liming Zhao,Xiang Liu
La 1- x A x MnO 3 (A = alkaline-earth or alkali metal) perovskites with large temperature coefficient of resistivity ( TCR ) offer immense opportunity for the application in high-performance infrared bolometer. However, numerous studies have revealed that the manganite films with large TCR values are not easily obtained by various fabrication technologies. Herein, a facile sol-gel spin-coating technique was used to prepare La 1- x Ca x MnO 3 (LCMO, 0.280 ≤ x ≤ 0.375) films. All the samples were highly oriented along the out-of-plane direction of La 0.3 Sr 0.7 Al 0.65 Ta 0.35 O 3 (001) substrates. With the rise in Ca doping amount, the resistivity of the films first decreased, and then, increased. This change can be attributed to the competition between the carrier concentration and lattice distortion. The LCMO films displayed large TCR and low-field magnetoresistance ( MR ) values, which exceeded those of previously reported thin films. The maximum TCR and low-field MR values were observed at x = 0.330, reaching 30.13% K −1 (266.43 K) and 68.6% (270.08 K), respectively. The La 0.67 Ca 0.33 MnO 3 film with large TCR and MR values presents potential for the applications in high-sensitivity infrared bolometers and magnetic sensors.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
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