ACS Macro Letters
·
2012
·
IF 0
Weichao Shi,Fenghua Chen,Yan Zhang,Charles C. Han
Polymer blends with dynamic asymmetry have attracted much interest recently. In this study, we report a more typical case where the dynamically asymmetric system is highly immiscible. We find that there is a transient network growth and phase inversion for the slow minor component. The network structure shows a hierarchical growth behavior, which is the result of competition between a slow relaxation-controlled concentration growth on local scale and a fast hydrodynamic growth on large scale. When phase separation couples with a subsequent crystallization, the interfacial boundary may assist lateral crystallization and irregular spherulites would grow epitaxially around the amorphous component-rich domains. The interface may play the role of substrates for heterogeneous nucleation. These phenomena may help us with morphological control in material processing.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
Advanced Energy Materials
·
2023
·Vol. 13
·期 12
·2203519
·
IF 27.8
Huijun Liao,Zizhen Zhou,Sikang Zheng,Yuling Huang,Guang Han,Guoyu Wang,Zhengyong Huang,Xu Lu,Jian Li,Xiaoyuan Zhou
High-temperature thermoelectric (TE) materials are common wide-gap semiconductors that are used in order to prevent the bipolar effect. Here, a potential high-temperature n -type TE material SmS with a simple NaCl structure that demonstrates a narrow band gap of ≈0.25 eV is reported. As expected, a temperature-dependent carrier concertation is observed, which is attributed to the thermal activation of electrons from valence band edge to conduction band. Interestingly, the intrinsic activation does not cause any sign of a bipolar effect. Density functional theory calculations suggest that the phenomenon originates from the strong electron-hole asymmetry in the electronic structure and the electron-to-hole conductivity ratio is as high as 700–900. As a result, the activated minority carriers barely participate in the TE transport and the maximum power factor reaches 1.41 mW K −2 m −1 at 1123 K. By further alloying with Se to reduce lattice thermal conductivity, a peak zT of ≈1.1 is obtained in Sm 1.08 S 0.78 Se 0.22 at 1123 K, which is among the best n -type high-temperature thermoelectrics. This study proves high-temperature TE materials can be found in narrow-gap semiconductors, which significantly enriches the scope of possibilities for novel TE materials.
研究领域:
材料科学
·
凝聚态物理
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2020
·
IF 3.28
Hao Tang,Hua Zhou,Xianhua Cheng
The green and red upconversion (UC) emissions of 35 mol% Ca 2+ doped β-NaYF 4 :Yb 3+ /Er 3+ microcrystals were improved to 102.8 and 43.1 times higher than those of Ca 2+ -free counterparts. X-ray powder diffraction spectra, scanning electron microscopy, Fourier transform infrared spectroscopy , upconversion luminescence (UCL) spectroscopy and Judd-Ofelt analysis were performed to investigate the mechanism of UCL intensity enhancement caused by Ca 2+ doping. The hexagonal-to-cubic phase transition was observed when Ca 2+ doping concentration exceeded 35 mol%. The incorporation of Ca 2+ into hexagonal microcrystals lattice induced unit cell volume enhancement and microcrystals surface to volume ratio variation, which affected the UCL intensity by hindering the non-radiative energy loss process via Yb 3+ /Er 3+ ions and changing the amount of surface quenchers adsorbed on the microcrystals surface. The hypersensitive transition related local crystal field asymmetry around Er 3+ in the grown hexagonal microcrystals was also investigated by Judd-Ofelt analysis but unexpectedly found to be the less dominant factor for the UCL intensity variation. This study helps to realize the mechanism of impurity ion doping resulted UCL intensity enhancement, which is instructive for high-performance UC microcrystals synthesis.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
Surfaces and Interfaces
·
2022
·
IF 6.137
Yefeng Feng,Li Liu,Hongrong Qiu,Maolin Bo,Wanshan Duan,Qihuang Deng
Utilizing percolation of symmetric MXene filler easily achieves high dielectric constant in polymer/MXene composites. However, percolation leads to low breakdown strength . In present work, we have adopted a new strategy of employing asymmetric bimetallic VTiC MXene filler to fabricate composite dielectrics with highly insulating polyvinyl chloride (PVC) matrix. VTiC filler was prepared via heat-pressing and etching. PVC/VTiC composite films with varied filler contents were prepared via solution cast. Different surface work functions of VTiC were confirmed via density functional theory (DFT) calculations. Compared with several polymer/symmetric monometallic MXene composites in our prior works, PVC/VTiC composites show simultaneously improved dielectric and breakdown properties. In later, high dielectric constant stems from cooperation of filler's asymmetry and polymer/filler interface polarization, and high breakdown strength is rooted in matrix's ultrahigh insulation. Optimized PVC/VTiC composite with 10 wt% filler possesses a high dielectric constant of ∼203, low dielectric loss of ∼0.13 at 100 Hz and high breakdown strength of ∼374 MV m −1 at direct-current field. Innovation of this work is use of asymmetric MXene filler for constructing polymer-based composite dielectrics with promising properties. This work might pave a road for large-scale preparation of advanced dielectrics for capacitors.
研究领域:
材料科学
·
电气工程
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
Bin Shang,Yanbing Wang,Bo Peng,Ziwei Deng
Janus particles with controlled asymmetries and functionalities represent promising building blocks and functional materials due to their unique anisotropic features. Herein, we show a facile and general approach towards preparing colloidal Janus particles with adjustable surface asymmetries and functionalities based on monolayer colloidal crystal (MCC) templates combined with mussel-inspired polydopamine (PDA) chemistry at an air-water interface. First, monodisperse colloidal polystyrene/polydopamine (PS/PDA) Janus particles with tunable asymmetrical geometries are synthesized by polymerizing dopamine onto two-dimensional (2D) polystyrene (PS) monolayer colloidal crystals formed at the air-water interface. Moreover, the good chemical reactivity of the PDA coating makes it a versatile platform to introduce a variety of functional materials, e.g., metal nanoparticles and organic molecules, producing colloidal Janus particles with adjustable functionalities. Finally, we demonstrate this synthetic strategy not only provides a controllable method for the fabrication of monodisperse colloidal Janus particles but also opens up a new Janus platform for artificially designed Janus particles with tunable asymmetries and functionalities.
研究领域:
材料科学
·
化学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
NATURE GENETICS
·
2016
·Vol. 49
·期 1
·119-124
·
IF 31.616
Shao Changwei,Bao Baolong,Xie Zhiyuan,Chen Xinye,Li Bo,Jia Xiaodong,Yao Qiulin,Ortí Guillermo,Li Wenhui,Li Xihong,Hamre Kristin,Xu Juan,Wang Lei,Chen Fangyuan,Tian Yongsheng,Schreiber Alex M,Wang Na,Wei Fen,Zhang Jilin,Dong Zhongdian,Gao Lei,Gai Junwei,Sakamoto Takashi,Mo Sudong,Chen Wenjun,Shi Qiong,Li Hui,Xiu Yunji,Li Yangzhen,Xu Wenteng,Shi Zhiyi,Zhang Guojie,Power Deborah M,Wang Qingyin,Schartl Manfred,Chen Songlin
Flatfish have the most extreme asymmetric body morphology of vertebrates. During metamorphosis, one eye migrates to the contralateral side of the skull, and this migration is accompanied by extensive craniofacial transformations and simultaneous development of lopsided body pigmentation1,2,3,4,5. The evolution of this developmental and physiological innovation remains enigmatic. Comparative genomics of two flatfish and transcriptomic analyses during metamorphosis point to a role for thyroid hormone and retinoic acid signaling, as well as phototransduction pathways. We demonstrate that retinoic acid is critical in establishing asymmetric pigmentation and, via cross-talk with thyroid hormones, in modulating eye migration. The unexpected expression of the visual opsins from the phototransduction pathway in the skin translates illumination differences and generates retinoic acid gradients that underlie the generation of asymmetry. Identifying the genetic underpinning of this unique developmental process answers long-standing questions about the evolutionary origin of asymmetry, but it also provides insight into the mechanisms that control body shape in vertebrates.
研究领域:
遗传学
·
发育生物学
·
比较基因组学
✓ 已验证
DOI
高影响因子
Science Advances
·
2025
·Vol. 11
·期 9
·
IF 12.5
Quanlin Chen,Mingwei Ge,Cong Geng,Jia Zhang,Linyue Gao,Zhuanzhuan Huang,Saike Wang,Yanxing Feng,Xinxin Yue,Saif M. H. Qaid,Xuewen Fu,Mei Wang,Yuanzhi Jiang,Mingjian Yuan
Developing direct full-stokes imaging polarimetry is essential for various applications but remains challenging. Perovskites have superior optoelectronic properties and structural diversity, making them ideal candidates for high-performing direct full-stokes polarimetry. However, perovskite suffers low chiroptical activity due to inefficient chiral transfer, which greatly limits its circular-polarization-vector discrimination. These issues urgently require remedy. Here, we demonstrate that perovskites’ chiroptical activity is highly related to their structural chiral-distortion extent. We propose using halide mixing to construct asymmetric chiral transfer to heighten its structural chiral-distortion extent. Accordingly, we report a 16-fold increment in the optical chiroptical activity. Further ab initio calculations verify that the enhancement is due to the strengthened magnetic transition dipole in mixed-halide structures. We herein report a self-powered, direct full-Stokes polarimetry with a high detectivity up to 1.2 × 1012 Jones and low detection errors (ΔS1–3 ≤ 5.0%). We further showcase their application in full-stokes imaging polarimetry with the lowest detection errors yet.
研究领域:
材料科学
·
光学工程
·
物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMISTRY OF MATERIALS
·
2019
·
IF 10.159
Chao Deng,Qian Zhang,Cong Fu,Fangzhou Zhou,Wuli Yang,Deliang Yi,Xingdong Wang,Yi Tang,Frank Caruso,Yajun Wang
SiO2 nanotubes (NTs), with uniform diameter (∼25 nm) and tailored shell thickness (1–5 nm), and featuring chemically asymmetric surfaces (a silane-functionalized exterior surface and a negatively charged (−Si–O–) interior surface) are prepared by a facile, template-free approach. Owing to their chemically asymmetric properties, positively charged cargoes can be selectively loaded with high content into the SiO2 NTs via electrostatic interaction. Mediated by polyamidoamine dendrimers preassembled in the NTs, different noble metal nanoparticles can be selectively deposited inside the NTs with high density and uniform size. Owing to their high specific surface area and elongated pore structure with lengths up to several micrometers, the SiO2 NTs exhibit a high loading capacity (80 wt %) for positively charged therapeutic agents, which exhibit sustained cargo release properties on the order of several months if the NTs are assembled into a membrane structure.
研究领域:
材料科学
·
生物医学工程
·
药学
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2024
·
IF 6.7
Weiwei Zhang,Miaoyu Chen,Qun Ma,Zhixiao Si,Sanmei Jin,Qiujiao Du,Limin Zhang,Yu Huang,Fan Xia
Artificial solid-state nanochannels featuring precise partitions present a highly promising platform for biomarker detection. While the significance of probes on the outer surface (POS) has been relatively overlooked in the past, our research highlights their crucial role in biosensing. Furthermore, the contribution of POS on the bullet-shaped asymmetric nanochannels has not been extensively explored until now. Here, we fabricated a series of bullet-shaped nanochannels, each featuring a distinct asymmetric structure characterized by different tip- and base-pore diameters. These nanochannels were further modified with explicit distributions at the inner wall (PIW), the outer surface (POS), and their combination (POS + PIW) for lysozyme sensing. The impact of diameters, structural asymmetry, and surface charge density on the sensing efficacy of POS and PIW was thoroughly examined through experimental investigations and numerical simulations. POS demonstrates great individual sensing performance for lysozyme within a broad concentration range, spanning from 10 nM to 1 mM. Furthermore, it improves the sensitivity when combined with PIW, particularly within the nanochannels featuring the smaller base-pore diameter, resulting in a 2-fold increase in sensing performance for POS + PIW compared to PIW at a concentration of 10 nM. These findings are substantiated by numerical simulations that closely align with the experimental parameters. The contributions of POS are notably amplified in the presence of smaller base pores and a higher degree of asymmetry within the bullet-shaped nanochannels. These findings elucidate the mechanism underlying the role of POS within bullet-shaped asymmetric nanochannels and open up new avenues for manipulating and enhancing the sensing efficiency.
研究领域:
生物传感
·
纳米技术
·
蛋白质分析
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2017
·Vol. 53
·期 2
·1395-1403
·
IF 2.599
Yi Mengji,Liu Yuefeng,Gao Huiping,Huang Zhangyu,Liang Jiwei,Mao Yanli
In this manuscript, Ni 2+ ions-doped NaYF 4 :Yb 3+ /Er 3+ nanoparticles have been synthesized via a modified hydrothermal method. The upconversion luminescence intensities of the green (G) and red (R) emission of NaYF 4 :Yb 3+ /Er 3+ co-doped with 20 mol% Ni 2+ ions are the strongest which increase 32.84 and 20.99 times than that without doping Ni 2+ , respectively. In addition, the R/G ratio decreases with the concentration of Ni 2+ increasing from 0 to 40 mol%. The underlying reason for luminescence enhanced and the R/G ratio decreased by Ni 2+ doping is explored by a series of controlled experiments, and the mechanism based on the crystal field asymmetry, different substitution by Ni 2+ , the energy transition of Er 3+ is studied in detail. The study indicates that the misshapen crystal field plays an important role in enhancement fluorescence emission, and several factors affect the R/G ratio including the crystal field, the substitution site and the energy transition. Our result may play a certain function for study and design of high-performance upconversion materials.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Journal of the American Chemical Society
·
2024
·
IF 14.4
Xueru Guo,Zhi Tong,Anqi Li,Yajie Zhou,Zeyi Li,Jing Lin,Yaxin Wang,Mingjiang Zhang,Taotao Zhuang
Chiral plasmonic nanomaterials─with their significant applications in protein detection, drug screening, and enantioselective sensing─necessitate an industrialized fabrication procedure to enhance their commercial viability. However, the prevailing manufacturing of chiral plasmonic nanoparticles and assemblies heavily leans on manual intervention, causing time-consuming and quality-inconsistent concerns. Here, we develop an automated, continuous mechanical synthesis system that consistently sprays metal nanowires to create chiroplasmonic assemblies: a macroscopic twisted layered structure comprising equivalent linear birefringence layers, approximate linear polarizer layers, and a precise angular offset between them. Utilizing the synthesis-with-automation system, we scale up the production of chiral plasmonic films, generating high optical asymmetry (g-factor, with the order of 10–1) across a broadband ranging from ultraviolet to near-infrared wavelengths. We further introduce the portable chiral sensing, expanding plasmonic assemblies into flexible materials and integrating them with wearable real-time display devices. Our mechanically driven, continuous synthesis of chiral plasmonic structures presents an intriguing pathway to facilitate functional chiral structures toward practice.
研究领域:
纳米材料科学
·
光学工程
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Jiajun Feng,Yongxin Yu,Hongji Song,Zibo Chen,Yingxiang Zhu,Jiahui Liu,Jingtian Xie,Lianfen Chen,Junhao Li
A structural design strategy was employed to develop NaGd2Ga2InGe2O12:Sm3+ (NGGIG:Sm3+) garnet phosphors, optimizing the local coordination environment to enhance luminescence performance. By tailoring site occupation, Sm3+ ions were incorporated into an asymmetric crystal field, where a statistical probability model confirmed that ∼97% of Sm3+ ions reside in distorted coordination environments, promoting electric dipole(ED) transitions. The phosphors exhibit a high red-to-orange (R/O) intensity ratio of 2.97, contributing to enhanced red emission. CIE chromaticity coordinates of (0.61, 0.39) indicate a significant shift toward the red region, and the phosphors retain over 70% of their luminescence intensity at 400 K, demonstrating good thermal stability. These characteristics make NGGIG:Sm3+ a promising candidate for high-performance red phosphors in solid-state lighting applications, highlighting the effectiveness of site engineering in garnet structures for optimizing luminescence efficiency and stability.
研究领域:
材料科学
·
光学材料
·
固态照明
·
无机化学
·
发光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）