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(Yb_(0.25)Lu_(0.25)Er_(0.25)Y_(0.25))_(2)Si_(2)O_(7)高熵硅酸盐热环境障涂层的性能研究

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中国稀土学报 2024年第4期42卷 752-761,I0004页

作者：王泽通董淑娟毛传勇蒋佳宁邓龙辉曹学强武汉理工大学硅酸盐建筑材料国家重点实验室湖北武汉430070

通过高熵化设计制备了一种新型焦硅酸盐涂层材料(Yb_(0.25)Lu_(0.25)Er_(0.25)Y_(0.25))_(2)Si_(2)O_(7),采用大气等离子喷涂(APS)在碳化硅纤维增强碳化硅陶瓷复合材料(SiC_(f)/SiC-CMCs)表面制备了(4RE_(0.25))_(2)Si_(2)O_(7)一体化热环境障涂层(TEBCs)体系和LaMgAl_(11)O_(19)/Lu_(2)Si_(2)O_(7)热/环境障涂层(T/EBCs)体系。通过研究两种涂层体系的微观结构、热物理性能、水氧腐蚀性能以及热循环寿命等结果发现:APS制备的(4RE_(0.25))_(2)Si_(2)O_(7)涂层从室温到1500℃为稳定的β相,(4RE_(0.25))_(2)Si_(2)O_(7)涂层不存在成分偏析,热导率和热膨胀系数相对Lu_(2)Si_(2)O_(7)涂层有所降低,更适合作为一体化TEBCs使用;(4RE_(0.25))_(2)Si_(2)O_(7)TEBCs体系的水氧腐蚀寿命高于80 h,LaMgAl_(11)O_(19)/Lu_(2)Si_(2)O_(7)T/EBCs体系的水氧腐蚀寿命低于80 h;(4RE_(0.25))_(2)Si_(2)O_(7)TEBCs体系的热循环寿命为168次;高熵化设计使焦硅酸盐涂层CTE适配度提高,断裂韧性增强,进而增加了TEBCs体系的热循环寿命。

关键词：高熵化设计热环境障涂层(TEBCs) 相稳定性高温水氧腐蚀热循环焦硅酸盐稀土

碳化硅陶瓷基复合材料表面环境障涂层结合强度

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材料工程 2024年第2期52卷 198-206页

作者：苏超群邓龙辉刘若愚蒋佳宁云海涛李归苗小锋陈文博易出山刘俐董淑娟曹学强中国航发南方工业有限公司湖南株洲412002 武汉理工大学硅酸盐建筑材料国家重点实验室武汉430070

SiC陶瓷基复合材料(SiC-based ceramic matrix composites,SiC-CMC)是发展高推重比航空发动机理想的高温结构材料。为了防止发动机服役环境下燃气(富含H2O和O_(2))对SiC-CMC的腐蚀,需要在其表面制备抗水氧腐蚀、抗燃气冲刷和抗热冲击性... 详细信息

SiC陶瓷基复合材料(SiC-based ceramic matrix composites,SiC-CMC)是发展高推重比航空发动机理想的高温结构材料。为了防止发动机服役环境下燃气(富含H2O和O_(2))对SiC-CMC的腐蚀,需要在其表面制备抗水氧腐蚀、抗燃气冲刷和抗热冲击性能优异的环境障涂层(environmental barrier coatings,EBCs)。在评价EBCs性能的诸多因素中,其与SiC-CMC基体之间的结合强度是一个重要技术指标,但结合强度的极限值一直未被探究清楚。本工作研究影响结合强度的主要因素,包含SiC-CMC基体状态、单晶Si的拉伸强度极限,以及Si黏结层的制备工艺等,获得了制备最高结合强度的有效途径。在EBCs与SiC-CMC组成的体系中,基体内部SiC纤维布之间的界面是结合强度最薄弱的部位,其次是EBCs的Si层。整个体系的结合强度极限值是15 MPa,它是单晶Si在[400]晶向的拉伸强度极限。采用大气等离子喷涂或者超音速火焰喷涂的Si黏结层结合强度相似,均低于同样工艺制备的莫来石或Yb2Si2O7涂层。

关键词：碳化硅复合材料环境障涂层结合强度

cPCN-Regulated SnO_(2) Composites Enables Perovskite Solar Cell with Efficiency Beyond 23%

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Nano-Micro Letters 2021年第7期13卷 12-27页

作者： Zicheng Li Yifeng Gao Zhihao Zhang Qiu Xiong longhui deng Xiaochun Li Qin Zhou Yuanxing Fang Peng Gao CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002FujianPeople’s Republic of China College of Chemistry Fuzhou UniversityFuzhou 350116People’s Republic of China Laboratory for Advanced Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021People’s Republic of China

Efficient electron transport layers(ETLs)not only play a crucial role in promoting carrier separation and electron extraction in perovskite solar cells(PSCs)but also significantly affect the process of nucleation and growth of the perovskite ***,crystalline polymeric carbon nitrides(cPCN)are introduced to regulate the electronic properties of SnO_(2) nanocrystals,resulting in cPCN-composited SnO_(2)(SnO_(2)-cPCN)ETLs with enhanced charge transport and perovs-kite layers with decreased grain ***,SnO_(2)-cPCN ETLs show three times higher electron mobility than pristine SnO_(2) while offering better energy level alignment with the perovskite *** SnO_(2)-cPCN ETLs with decreased wettability endow the perovskite films with higher crystallinity by retarding the crystallization *** the end,the power conversion efficiency(PCE)of planar PSCs can be boosted to 23.17%with negligible hysteresis and a steady-state efficiency output of 21.98%,which is one of the highest PCEs for PSCs with modified SnO_(2) ***_(2)-cPCN based devices also showed higher stability than pristine SnO_(2),maintaining 88%of the initial PCE after 2000 h of storage in the ambient environment(with controlled RH of 30%±5%)without encapsulation.

关键词： Electron transport layer Perovskite solar cell Carbon nitride SnO_(2)

Influence of synthesis temperatures on the crystalline grain growth and morphology of lanthanum magnesium hexaaluminate

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Journal of Rare Earths 2017年第12期35卷 1226-1232页

作者： Junbin Sun Jinshuang Wang Wenzhi Huang Yu Hui Xin Zhou Lifen Li Jianing Jiang longhui deng Yunya Niu Shujuan Dong Xueqiang Cao State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology Science and Technology on Advanced Ceramic Fibers and Composites Laboratory National University of Defense Technology Atmospheric Environment Research Center Shenyang Academy of Environmental Sciences

Lanthanum magnesium hexaaluminate（LaMgAl（11）O（19）, LMA） was prepared at different temperatures by solid-state reaction. Phase compositions and crystal morphologies of specimens synthesized at different temperatures were investigated using X-ray diffraction（XRD）, scanning electron microscopy（SEM）. It was observed that the crystalline grain size of LMA was not only dependent on the preparation temperature but also on its powder morphology. In the temperature range of 1300 e1550℃, LMA showed platelet grain and the average crystalline grain size increases with the increase in temperature. At1600℃, if the powder was sintered for two times, the equiaxed grain could be found with the decrease in grain space, resulting in the reduction of the crystalline grain size. Styles of specimens（powder or disk） might have no obvious influence on morphologies and sizes of LMA crystalline grains which were synthesized with the well-dispersed raw material mixtures. The synthesis temperature played a key role in influencing the free space for the formation and growth of crystalline grains.

关键词： Hexaaluminate Crystalline grain growth Crystal morphology

Widespread Bathyarchaeia encode a novel methyltransferase utilizing lignin-derived aromatics

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mLife 2023年第3期2卷 272-282页

作者： Tiantian Yu Haining Hu Xianhong Zeng Yinzhao Wang Donald Pan longhui deng Lewen Liang Jialin Hou Fengping Wang School of Oceanography Shanghai Jiao Tong UniversityShanghaiChina State Key Laboratory of Microbial Metabolism School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)ZhuhaiChina

Lignin degradation is a major process in the global carbon cycle across both terrestrial and marine ***,which are among the most abundant microorganisms in marine sediment,have been proposed to mediate anaerobic lignin ***,the mechanism of bathyarchaeial lignin degradation remains ***,we report an enrichment culture of Bathy-archaeia,named Candidatus Baizosediminiarchaeum ligniniphilus DL1YTT001(***),from coastal sediments that can grow with lignin as the sole organic carbon source under mesophilic anoxic *** possesses and highly expresses novel methyltransferase 1(MT1,mtgB)for transferring methoxyl groups from lignin monomers to cob(I)*** have no homology with known microbial methyltransferases and are present only in bathyarchaeial *** expression of the mtgB gene confirmed O-demethylation *** mtgB genes were identified in metagenomic data sets from a wide range of coastal sediments,and they were highly expressed in coastal sediments from the East China *** findings suggest that Bathyarchaeia,capable of O-demethylation via their novel and specific methyltransferases,are ubiquitous in coastal sediments.

关键词： Bathyarchaeia coastal sediments lignin-degrading lignin-derived aromatics specific methyltransferase

LaMeAl_(11)O_(19)/YSZ热障涂层热力学性能和热循环寿命

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无机材料学报 2022年第12期37卷 1259-1266页

作者：蔚海浪曹学强邓龙辉蒋佳宁武汉理工大学硅酸盐建筑材料国家重点实验室武汉430070

LaMeAl_(11)O_(19)陶瓷具有独特的晶体结构,优异的热力学性能,低热导率,高温相稳定性等特点,是一类非常有应用前景的热障涂层(TBC)材料。本研究通过大气等离子喷涂(APS)制备了LaMeAl_(11)O_(19)/YSZ(Me=Mg,Cu,Zn)双陶瓷层热障涂层。通... 详细信息

LaMeAl_(11)O_(19)陶瓷具有独特的晶体结构,优异的热力学性能,低热导率,高温相稳定性等特点,是一类非常有应用前景的热障涂层(TBC)材料。本研究通过大气等离子喷涂(APS)制备了LaMeAl_(11)O_(19)/YSZ(Me=Mg,Cu,Zn)双陶瓷层热障涂层。通过对涂层进行火焰热循环测试并结合扫描电子显微镜、X射线衍射仪等分析技术对涂层进行失效分析。结果表明,LaMgAl_(11)O_(19)(LMA)、LaZnAl_(11)O_(19)(LZA)和LaCuAl_(11)O_(19)(LCA)粉末在等离子喷涂过程中发生了分解,导致三种涂层中磁铅石相含量的差异,从而影响三种涂层的热循环寿命。由于LaMeAl_(11)O_(19)层与YSZ层的热膨胀系数不匹配以及非晶相重结晶产生的体积收缩,LaMeAl_(11)O_(19)层从YSZ层上剥落。YSZ层暴露在高温下,加速了烧结和TGO的生长,又促进了YSZ层剥落。低温下,LaMeAl_(11)O_(19)的热导率随着Me原子序数增加而降低;高温下,与LMA和LZA相比,LCA涂层红外发射率最高(0.88,600℃),削弱了光子传导对热导率的贡献,导致热导率降低,LCA在高温红外辐射涂层中具有潜在的应用价值。

关键词：热障涂层磁铅石型稀土六铝酸盐火焰热循环热力学性能

Spherical cationic polymer networks with porphyrin photosensitizer for sustainable and efficient photocatalysis

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Nano Research 2024年第5期17卷 3934-3941页

作者： Lingling Zhang Liwei Wu Junhui Bao longhui Li Zejun Liu Feng Bai Jie Ju Xi Yao Key Laboratory for Special Functional Materials of Ministry of Education School of Materials Science and EngineeringHenan UniversityKaifeng 475004China Department of Chemistry City University of Hong KongKowloonHong Kong 999077China

The continuous and sustainable photo-activity on micro-or nano-carriers has always been a key stepping stone in the industrialization of photo-catalysis,photo-synthesis,and ***,we report a new series of positively charged hollow microspheres carrying porphyrin *** hollow spheres are formed through crosslinking of well-ordered porous thin laminates,initiated by co-assembly of regular monomers and those decorated with porphyrin *** the surface of an individual sphere,densely distributed positive sites attract anionic *** superficial porphyrin decomposes the accumulated reactants under 1 *** degradation and release of products,the photoactive sites are thereby *** demonstrate that polymer network(1:10)exhibited superior sustainable photocatalytic performance with complete degradation of methyl orange(MO)in 40 min with no observable performance deterioration after six *** established close loop of adsorption-reaction-release cycle makes possible many efficient and continuous photo-catalytic processes.

关键词： hydrogen bonding assembly porphyrin sustainable photo-activity anionic pollutant

热处理温度对LaMgAl_(11)O_(19)涂层热/力学性能的影响

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无机材料学报 2022年第9期37卷 925-932页

作者：安文然黄晶琪卢祥荣蒋佳宁邓龙辉曹学强武汉理工大学硅酸盐建筑材料国家重点实验室武汉430070

大气等离子喷涂制备的LaMgAl_(11)O_(19)(LMA)热障涂层无定型相含量较高,会严重影响涂层服役寿命。通过900~1600℃不同温度热处理12 h,研究晶粒尺寸和孔隙率等微观结构和无定形相含量对LMA涂层力学、热物理以及抗热震性能的影响。结果表... 详细信息

大气等离子喷涂制备的LaMgAl_(11)O_(19)(LMA)热障涂层无定型相含量较高,会严重影响涂层服役寿命。通过900~1600℃不同温度热处理12 h,研究晶粒尺寸和孔隙率等微观结构和无定形相含量对LMA涂层力学、热物理以及抗热震性能的影响。结果表明:喷涂态LMA涂层具有900和1163℃两个结晶温度点。900℃热处理后,LMA涂层中含有较多的无定形相以及最高的孔隙率((18.88±2.15)%),1000℃测试时,具有最低的热扩散系数(0.53 mm^(2)/s);由于重结晶和烧结作用使得无定型相含量和孔隙率降低,1100~1400℃之间热处理的涂层具有较高的硬度(1100℃时达到最高值(12.08±0.58)GPa);1300℃热处理的涂层中含有大量微米级片状晶,具有较高的应变容限以及平均热循环寿命(588次);热处理温度达到1500℃时,由于片状晶平行堆叠,晶粒厚度迅速增加,孔隙率增加,力学性能显著降低。热震过程中由于热应力的反复作用,涂层内出现晶粒破碎和裂纹扩展等现象,导致涂层最终失效。

关键词： LaMgAl_(11)O_(19) 热障涂层热处理热/力学性能

On-chip integrated GeSe_(2)/Si vdW heterojunction for ultravioletenhanced broadband photodetection,imaging,and secure optical communication

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Nano Research 2024年第7期17卷 6544-6549页

作者： Zhiman Zhou Kunxuan Liu Di Wu Yunrui Jiang Ranran Zhuo Pei Lin Zhifeng Shi Yongtao Tian Wei Han longhui Zeng Xinjian Li School of Physics and Microelectronics Key Laboratory of Material Physics Ministry of EducationZhengzhou UniversityZhengzhou 450052China Department of Electrical and Computer Engineering University of California San DiegoLa JollaCalifornia 92093USA Institute of Microelectronics and Integrated Circuits School of MicroelectronicsHubei UniversityWuhan 430062China

Broadband photodetection,spanning from ultraviolet(UV)to infrared(IR),is pivotal in diverse technological domains including astronomy,remote sensing,environmental monitoring,and medical ***,current commercially available broadband photodetectors,predominately based on conventional narrow-bandgap semiconductors,exhibit limited sensitivity in the UV *** limitation,stemming from the significant energy disparity between the semiconductor bandgap and UV photon,narrows their application ***,we report an innovative approach involving the in-situ van der Waals(vdW)integration of two-dimensional(2D)GeSe_(2)layers onto a Si *** process yields a high-quality GeSe_(2)/Si vdW heterojunction device,which features a broad response range covering from UV to near-IR(NIR)with a greatly-enhanced sensitivity in the UV *** device possesses high responsivities of 325 and 533.4 mA/W,large detectivities of 1.24×10^(13)and 2.57×10^(13)Jones,and fast response speeds of 20.6/82.1 and 17.7/81.0μs under 360 and 980 nm,***,the broadband image sensing and secure invisible optical communication capabilities of the GeSe_(2)/Si heterojunction device are *** work provides a viable approach for UV-enhanced broadband photodetection technology,opening up new possibilities and applications across various scientific and technological domains.

关键词： germanium diselenide van der Waals(vdW)integration ultraviolet enhanced broadband photodetection imaging