JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2025
·
IF 3.8
Zijun Li,Shuo Wang,Mengqing Zhang,Jiayi Zheng,Tong Zhang
With the rapid development of laser technology, the safety of human and equipment is increasingly threatened by high-power laser. However, there are not any high-power laser protection materials without flame and smoke during irradiation. In this study, we investigated a series of RE 2 Ti 2 O 7 (RE = Y, La, Sm, Eu, Yb) ceramics with high reflectivity and low thermal conductivity and evaluated their laser ablation behaviors. The results showed that all RE 2 Ti 2 O 7 have high reflectivity comparable to that of metals, and their thermal conductivity is lower than 8YSZ. Laser ablation results showed all coatings were intact after irradiation under 500 W/cm 2 for 10 s. Even after irradiation under 1000 W/cm 2 for 10 s, no significant changes were observed in the Y 2 Ti 2 O 7 and La 2 Ti 2 O 7 coatings. Further exploration determined that the protection threshold of Y 2 Ti 2 O 7 was 84 s while that of La 2 Ti 2 O 7 was 163 s, indicating its superior laser protection capability. In conclusion, La 2 Ti 2 O 7 shows significant potential in high-power laser protection.
研究领域:
材料科学
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激光技术
✓ 已验证
产品关联
DOI
高影响因子
Chemistry-An Asian Journal
·
2024
·Vol. 19
·期 17
·e202400529
·
IF 3.5
Ying Zhang,Yujing Ren,Jingyan Hao,Juan Gao,Yurong Ma
Hyperspectral imaging technology can record the spatial and spectral information of the targets and significantly enhance the levels of military reconnaissance and target detection. It has scientific importance to mimic “homochromatic and homospectral” camouflage materials that have hyperspectral similarity with the green vegetation, one of the most common natural backgrounds. It is a big challenge to exquisitely simulate the spectral of green vegetation in visible and near-infrared windows because of the slight differences between the artificial green dyes and vegetation, the instability of chlorophylls, and the easy loss of hydroxide bands due to the loss of water from the camouflage materials. Herein, a novel kind of biomimetic material of green vegetation was designed through the incorporation of chlorophylls into the crystal lattices of single-crystalline anhydrous guanine microplates for the first time. The synthesized chlorophylls-doped anhydrous guanine crystals exhibit high reflectance intensity and depolarization effect, thus can be applied as biomimetic camouflage materials that mimic green vegetation with high reflectivity and low polarization in the visible and near-infrared regions. The factors influencing the formation of dye-doped organic crystals under mild conditions were thoroughly investigated and the characterizations using electron microscopies and fluorescence confocal laser scanning microscopy clearly confirm the occlusion of chlorophylls into the crystal lattices of guanine crystals. The thermal stability experiments clearly indicate that the chlorophylls-doped guanine crystals possess long-term stability at high temperature. This study provides a new strategy for the synthesis of multifunctional materials comprised of organic crystals.
研究领域:
材料科学
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仿生学
·
光谱学
✓ 已验证
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2023
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IF 4.9
Qianxiong Wen,Cong Zhao,Meilin Fu,Yusai Xu,Xiangjia Sun,Jiaying Zheng,Yanrong Liang,Weidong Xiang,Xiaojuan Liang,Zhaoping Chen
Phosphor-in-glass (PiG) has been prepared into various types of phosphor films owing to its simplicity process, exceptional color purity, and convenient color adjustability. Nevertheless, existing reflective PiGs films have encountered limitations in terms of stability and feasibility as reliable color converters, mainly attributed to issues related to thermal deposition and insufficient optical efficiency. Herein, we propose to use AlN substrate with superior thermal conductivity to coat the TiO 2 layer to obtain TiO 2 –AlN (TA), which enhances the reflectivity of blue light to facilitate the light conversion process. By incorporating highly thermally stable LuAG:Ce-PiGs on a TA substrate, the LuAG:Ce-PiTA converter exhibits a luminous flux of 1102 lm@6.4 W, and maintains a relative intensity of 94.6% at 473 K benefiting from the high thermal conductivity of 34.1 W/(m·K). The addition of CASN 3 :Eu to the color converter 50 L&10C-PiTA enables an impressive CRI of 90.7. Relative luminescence intensities of LuAG:Ce-PiTA and 50 L&10C-PiTA only decrease by 5.35% and 3.28%, respectively, in the 24 h illumination aging decay test of the reflective laser module. The results confirm the suitability of the optimally designed TA substrate for LuAG:Ce color converter applications in high-power reflective laser illumination.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Zhengdong Li,Xueying Zhang,Liwen Yan,Haiyan Du,Anran Guo,Ying Mu,Jiachen Liu
High emissivity coatings on hypersonic vehicle surfaces dissipate heat by emitting thermal radiation. While the difficulty of increasing emissivity limits the performance of coatings to improve heat-dissipation of the thermal insulation felt. Herein, a novel high-reflectivity and high-emissivity integrated double-layer coating was developed to enhance the thermal insulation performance of the alumina fiber fabric. The coating comprised of TiO 2 @SiO 2 (T@S) as reflective agent and ZrO 2 /SiC w (ZSC) as emittance agents, was applied on the surface of alumina fiber fabric (AFF). The reflecting effect of radiation heat from the high reflective agent enhanced the thermal insulation properties of the double-layer coating. In the wavelength range of 0.4–2.5 μm, the average emissivity of the ZSC coating was 0.83 and the average reflectivity of the T@S coating was 0.63. With continuous heating at 1400 °C for 10 min with a butane torch, the temperature on the backside of the T@S–ZSC-coated AFF remained relatively stable at 225 °C, which is notably decreased by 80 °C compared to that of the single-layer ZSC-coated AFF. The tensile strength of AFF with T@S–ZSC coating reached 35 MPa after being heat treated at 1200 °C. Moreover, the bonding strength between the coating and the AFF substrate was measured to be 0.15 MPa. The double-layer coating with high emissivity and reflectivity, along with a flexible AFF substrate, offers a promising solution for addressing the challenging of surface heat-dissipation in hypersonic vehicles.
研究领域:
材料科学
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航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
Advanced Composites and Hybrid Materials
·
2024
·Vol. 7
·期 1
·1-13
·
IF 23.2
Li Shuliang,Du Guomin,Pan Min,Wang Xiaoliang,Dong Xinyi,Huang Ting,Hu Dingyuan,Ren Tao,Li Xue,Chen Hong,Mai Xianmin
Passive daytime radiative-cooling materials (characterized by a high solar reflectance and thermal emittance) exhibit a cooling effect under direct sunlight with zero energy consumption, thereby decreasing the demand for air conditioning. Although various well-designed radiative-cooling materials have been reported to date, their syntheses are environmentally harmful and unsuitable for large-scale operation (as they involve complicated, high-cost, or solution-processed methods). In this study, a hierarchical-morphology coating for large-scale radiative-cooling applications was constructed by a one-step, inexpensive, solution-free, and environmentally friendly strategy. The hierarchical morphology (comprising nanospheres and micropores randomly dispersed throughout a polymer matrix) was fabricated through simple mechanical stirring (without the use of templates); no solvents or by-products were produced during the manufacturing process. The optimal coating showed high emissivity (95.1%) in the atmospheric-window band, strong solar reflectivity (94.0%), and a cooling power of 62.94 W m −2 (according to field tests). Moreover, covering the roof of a model with the as-prepared hierarchical-morphology coating reduced the average roof temperature by 11.5 ℃ (according to outdoor tests). According to simulations, the coating enabled annual cooling-energy-consumption savings in the range of 14.5–41.2% for typical buildings located in different climatic regions, indicating high potential as an energy-saving building-envelope material. Graphical Abstract A one-step, scalable and sustainable strategy has been developed to fabricate hierarchical-morphology coatings for passive daytime radiative cooling.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
POLYMER
·
2021
·
IF 4.43
Lu Qiu,Quanshan Liu,Rui Zhang,Tao Wen
Distributed Bragg reflectors (DBRs), the simplest photonic crystals, have received extensive attention due to their unique characteristics and appealing applications. Herein, we aim to demonstrate a facile and cost-effective approach for fabrication of organic/inorganic hybrids by using commercially available ultraviolet (UV)-curable resins to give DBRs with a high reflectance from only a few stacks of the organic/inorganic hybrid layer. With the use of the UV-crosslinked resins, the fabricated DBRs exhibit a high robustness against moisture and organic solvents. Also, for applications, the DBRs possess good performances with reversible response to organic solvent vapors. Moreover, the enhanced photoluminescence of methylamino lead bromide perovskite (CH 3 NH 3 PbBr 3 ) and tetraphenylethene (TPE) by hybrid DBRs was investigated. This work may provide new insights into the fabrication and applications of DBRs.
研究领域:
光学材料
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Shiyu Zhang,Aiguo Rao,Kai Lin,Qi Yao,Chunhui Niu,Lei Wang,Mingqing Yang,Xueqiong Bai,Yong Lv
Recently, the Fabry–Perot (F–P) cavity electrochromic devices, which are constructed by combining nano-size inorganic electrochromic material WO 3 and reflective metal layers, have attracted considerable attention due to their potentials in the fields of dynamic multicolor displays and active camouflage. However, in the few studies that have been reported, the peak reflectance of flexible F–P cavity multicolor electrochromic devices in the visible wavelength band is generally lower than 30 %, which limits their reflective display and camouflage effects in high-brightness environments. Thus, we have combined multicolor reflective electrochromic electrodes in WO 3 /Au asymmetric F–P nanocavity constructed by magnetron sputtering on a Nylon 66 porous substrate with a highly transparent UV-cured gel electrolyte and a PET plastic sealing procedure. As a result, a flexible and dynamic multicolor electrochromic skin with high reflectance (R max ＞50 %) and excellent flexibility (bending radius of 4 mm) has been fabricated. The WO 3 electrochromic layer at the top works as the dynamic dielectric layer in the broadband absorption Fabry–Perot cavity, and the inert metal Au layer at the bottom works as the reflective layer. The WO 3 /Au asymmetric F–P cavity can acutely capture the variation in optical constants of WO 3 due to the thickness change and electric-driven effects. This cavity facilitates the selective reflection and absorption of the energy distribution of the spectrum after the induced interferometric resonance. As a result, the cavity exhibits a rich array of structural colors, including ocher, taupe, yellow, orange, green, and violet. The electrochromic skin exhibits a fast switching time and maintains 99.43 % of the optical modulation amplitude (ΔR) after 110 coloring/bleaching cycles. It provides a potential option in the field of flexible high-brightness reflective displays and dynamic camouflage in the future.
研究领域:
材料科学
·
光学工程
·
柔性电子
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）