OPTICAL MATERIALS
·
2018
·
IF 2.32
Honghan Bu,Chen Xu,Guoyue Xu,Chuyang Liu,Shujuan Tan,Tengchao Guo,Shanshan Xiang
BCG/CaCl 2 /PEG-g-CDA composites with different mass ratios of BCG and CaCl 2 under constant PEG-g-CDA were synthesized via liquid-phase reaction method. The composites were analyzed and characterized using FT-IR, XRD , DSC and UV–vis. The results show that the color changes visibly from green to yellow by improving temperature from 50 °C to 62 °C, and turns back to green reversibly with temperature cooling back to room temperature. The infrared emissivity values increase rapidly at the temperature range of 50 °C–62 °C, and the maximum variation reaches 0.23. Furthermore, the mechanisms for thermochromic phenomenon and tunable infrared emissivity were also proposed. The reversible thermochromic phenomenon is attributed to the molecular structure transformation of BCG between ring-opened quinone structure and ring-closed lactone structure. The tunable emissivity at different temperatures is ascribed to the changes of resistivity under temperature fluctuations. Our results suggest that BCG/CaCl 2 /PEG-g-CDA composites are a potential candidate for smart adaptive camouflage in visible and infrared waveband.
研究领域:
材料科学
·
光学
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2025
·Vol. 46
·期 5
·118006
·
IF 6.2
Yulei Sun,Yuzhi Gao,Lianfeng Wu,Zhiyong Wang,Rongguo Wang,Xiaodong He,Fei He,Mingwei Li
High-emissivity coatings are vital for thermal protection systems in hypersonic vehicles, but there is often a conflict between the oxidation behaviors of sintering aids and high-emissivity fillers during the preparation. Here, we propose an in-furnace oxygen partial pressure regulation strategy to fabricate TaSi 2 /MoSi 2 /SiB 4 /borosilicate-glass coatings on the oxidisable substrate of carbon-bonded carbon fiber composites. The oxidation behavior of fillers under various oxygen partial pressures were conducted, and their oxidative characteristics were established. Furthermore, the sintering atmosphere and temperature were optimized to achieve a dense, uniform microstructure. The coatings exhibited an average emissivity of ∼0.94 in the 2.5–8 µm wavelength range, and a total hemispherical emissivity of 0.906 over 2.5–25 µm. After ablation for 1200 s at 1650 ℃, the coatings maintained structural integrity, with a mass ablation rate of 2.25 × 10 −4 g/s, a linear ablation rate of 3.75 × 10 −4 mm/s, which resulted from the formation of porous yet robust Ta 2 O 5 -enriched outer layers.
研究领域:
材料科学
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航空航天工程
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热防护系统
·
陶瓷涂层
·
高温材料
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2026
·
IF 6.3
Xiaohui Ma,Anran Guo,Liwen Yan,Lingyi Meng,Heng Chen,Xiaoxia Hu,Jinyu Wu,Jiachen Liu
As high emissivity emitters, traditional pseudobrookite ceramics are limited in thermal protection applications due to their structure degradation at high temperatures. In this work, a high-entropy pseudobrookite, (Mg,Co,Ni,Zn)Ti 2 O 5 , was designed, and CoTi 2 O 5 was selected as a single-component counterpart to evaluate the high-entropy effect on phase stability and emissivity. After heating at 1400 °C for 15 h, (Mg,Co,Ni,Zn)Ti 2 O 5 retained a single pseudobrookite phase with nearly unchanged emissivity, whereas CoTi 2 O 5 exhibited obvious phase degradation and emissivity deterioration. The higher 2.5–7 μm emissivity of (Mg,Co,Ni,Zn)Ti 2 O 5 was attributed to its narrower band gap (2.66 eV) and a higher oxygen vacancy fraction (56.87%). When coated on alumina-silica fiber fabric, the (Mg,Co,Ni,Zn)Ti 2 O 5 coating exhibited improved thermal-protection performance owing to its high infrared emissivity and reduced heat conduction, while maintaining good mechanical properties after heat treatment. These results demonstrate that (Mg,Co,Ni,Zn)Ti 2 O 5 is a promising high-emissivity ceramic for extreme thermal environments.
✓ 已验证
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2013
·Vol. 68
·期 1
·121-127
·
IF 1.66
Song Chen-lu,Wang Ju,Zeng Meng-long,Zhu Jian-qiang,Liu Yong,Xu Gang,Han Gao-rong
Fluorine-doped TiO 2 thin films featuring columnar structure were prepared on fluorine-doped tin oxide (SnO 2 :F) substrate using a sol–gel method. The F doping ratios were varied in the range of 0–8 %. The effect of [F]/[Ti + F] ratio on the structural, morphological, optical, photocatalytic and low-emissivity properties has been investigated in detail. X-ray diffraction studies revealed that all the composited films are mainly composed of anatase TiO 2 and rutile SnO 2 without other phases. The prepared TiO 2 :F films possessed the columnar morphology with the single layer thickness ranging from 28 to 31 nm. The best photocatalytic activity was obtained for the films with 4 % F doping ratio which is mainly attributed to the highest crystallization and crystallite size. The transmission and hemispherical emissivity of the composite films could still reach approximately 70 % and 0.20, which match the requirements of the Chinese National Standard (GB/T18915.2-2002), promoting the films for the practical applications.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
Advanced Composites and Hybrid Materials
·
2025
·Vol. 8
·期 6
·419
·
IF 21.8
Yu Sike,Bao Yan,Zhang Wenbo,Gao Lu,Guo Ruyue,Liu Chao,Ma Jianzhong
Developing a textile capable of achieving infrared stealth under Joule heating conditions is critical for enhancing the operational effectiveness and survivability of combat troops in challenging climates. Here, a novel type of silver nanowires/bacterial cellulose/carbon fibers composite fabric (ABCF) inspired by the multi-layered structure of beetle elytra and the dual-mode thermal management system was designed for infrared stealth at Joule heating via a facile sewing method. The introduction of an inner layer consisting of carbon fibers serves as an effective heater producer, demonstrating excellent Joule heating performance (~ 210 °C at 3 V). The interlayer made from bacterial cellulose aerogel exhibits thermal insulation properties (0.028 W/m·K) and flexibility, functioning as a barrier that mitigates heat transfer through its layer-stacking structure under directional thermal conduction. Meanwhile, the upper layer comprised of silver nanowires provides low emissivity (~ 0.15) and cooperates with the aerogel to achieve infrared stealth. As a result, ABCF achieves both a significant reduction in thermal radiation temperature for targets and long-term infrared stealth stability (~ 55 °C maintained for 8400 s), with experimental feasibility validated through COMSOL simulations. Impressively, ABCF has been effectively utilized in the construction of tents, further highlighting its potential for multifunctional applications in the field of thermal management.
研究领域:
材料科学
·
纺织工程
·
红外技术
·
热管理
·
仿生学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）