Materials Horizons
·
2022
·Vol. 10
·期 2
·454-465
·
IF 15.717
Jianbo Li,Yanxia Wang,Xue Jiang,Zhen Tian,Huijun Kang,Zongning Chen,Enyu Guo,Zhiqiang Cao,Tongmin Wang
The thermal conductivity of superlattices is strongly reduced as compared to that of the parent materials due to phonon-scattering and thermal boundary resistances at the superlattice period interfaces. Herein, homogenous superlattices consisting of homogenous structural CeδCa1−δTiO3 and CaTi1−δCeδO3 alternate layers were obtained through a variable-valence Ce doping, providing multi-quantum well interfaces between the alternate layers due to Ce-substitution at Ca and Ti sites, respectively. This material comprising these homogenous superlattices displayed a significantly reduced lattice thermal conductivity of 1.82 W m−1 K−1 and a record high zT value of 0.405 at 1031 K in CaTiO3-based thermoelectric materials. This strategy of synthesizing homogeneous superlattices provides a cost advantage over heterogeneous superlattices prepared by the molecular beam epitaxy method and paves a route for preparing bulk superlattices with unique thermoelectric properties rooting in the quantum domain limiting effect.
研究领域:
材料科学
·
热电学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2019
·Vol. 48
·期 11
·7068-7075
·
IF 1.676
Li Shuhui,Zhou Ying,Cui Lijun,Ge Zhenhua,Feng Jing
In 2 O 3 (ZnO) k superlattice ceramics are promising oxide thermoelectric materials, as superlattice interfaces are effective in scattering phonons and filtering low-energy electrons to decrease thermal conductivity and improve the figure of merit ( ZT ) value. In this work, homologous compounds were prepared by solid-state reaction method using ZnO and In 2 O 3 as raw materials. Phase purity and crystal structure were characterized by x-ray diffraction, revealing that In 2 O 3 (ZnO) k crystallizes in an R3 m space group for odd k values and P6 3 /mmc for even k values. The study of thermoelectric (TE) properties showed that as k increased, the thickness of InO(ZnO)
+ 3
also increased, while the electrical conductivity, thermal conductivity, Seebeck coefficient, power factor and ZT value were all decreased. In 2 O 3 (ZnO) 3 samples obtained a maximum power factor of 651 μ W m −1 K −2 at 973 K, and also achieved a maximum ZT value of 0.24 at 973 K.
研究领域:
材料科学
·
凝聚态物理
·
能源转换技术
✓ 已验证
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2024
·
IF 2.9
Ye Gao,Lingli Wan,Yuqing Song,Shan Gao,Nan Yan,Fan Wu,Yanqiu Du
Programmable organization of uniform organic/inorganic functional building blocks into large-scale ordered superlattices has attracted considerable attention since the bottom-up self-organization strategy opens up a robust and universal route for designing novel and multifunctional materials with advanced applications in memory storage devices, catalysis, photonic crystals, and biotherapy. Despite great efforts have been made in the construction of the superlattice materials, there still remains a challenge in the preparation of organic/inorganic hybrid superlattices with tunable dimensions and exotic configurations. Here, we report the spontaneous self-organization of polystyrene-tethered gold nanoparticles (AuNPs@PS) into freestanding organic/inorganic hybrid superlattices templated by the diethylene glycol-air interface. The resulting multilayer 3D superlattices exhibit hexagonally honeycomb and periodically tetrahedral lattice after the evaporation of AuNPs@PS building blocks at the liquid-air interface. Notably, a particular Moiré pattern originating from the twisted stacking of the adjacent layers is observed when the twist angle is 30°, leading to the exquisite quasi-crystalline packing with 12-fold rotational symmetry. In addition, the interparticle distance and gap within the 2D superlattice can be precisely regulated by adjusting the length of polymer segments, thereby generating the distinctive 3D graphene-skeleton configurations in the freestanding superlattice. This finding presents a highly efficient and versatile way to artificially produce multifunctional organic/inorganic hybrid superlattice materials with adjustable dimensions and internal configurations.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Energy Materials
·
2022
·
IF 6.959
Zhiwen Wang,Chuanrui Zhang,Jun Zhang,Jia liang,Zhenguo Liu,Fengling Hang,Yuxue Xuan,Xia Wang,Mengran Chen,Shaowen Tang,Peng-an Zong
Construction of an inorganic/organic superlattice-based film has been proven effective in enhancing thermoelectric (TE) performance as well as flexibility by a variety of mechanisms, typically for two-dimensional (2D) TiS2-based flexible TEs. MXenes, typically, Ti3C2Tx, are a type of 2D material widely investigated in fields of flexible batteries and electromagnetic shielding, among others. However, they have rarely been reported in flexible TEs. One of the key factors is that the surface termination groups (−T) on an MXene could trap electrons, restricting the electronic transport. Herein, −T groups were tailored and substituted by organic ions (−HA) by facile preannealing, exfoliation, and reassembly. The intercalation of −HA introduced Ti–N bonding, forming a flexible MXene/organic superlattice film. The electrical conductivity of the superlattice film was increased by 5 times to 1.6 × 105 S m–1 due to defect reduction as well as the electron injection effect. While the Seebeck coefficient was maintained, the power factor was increased from 4 to 18 μW m–1 K–2. The TE module based on the superlattice film revealed an output power of 7.6 nW at a temperature gap of 50 K. This work opens up an avenue of fabricating flexible MXene-based TE films by tailoring the surface termination group and constructing inorganic/organic superlattice structures.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
高影响因子
Advanced Physics Research
·
2023
·Vol. 2
·期 11
·2200125
·
IF 0
Yuanlong Li,Mengruizhe Kong,Wei Bai,Liang Sun,Huiyi Li,Chong Xiao,Yi Xie
The development of nano–manufacture technology in the twenty-first century has paved the way for artificial nanostructure constructions like man–made superlattices, providing historical breakthroughs in thermal physics and thermoelectrics by the modulation of phonons. Still, high–performance thermal insulators haven't come into operation due to the arduousness, costing and unscalability of artificiality. Herein, intentional engineering on a so–called ‘natural superlattice’ with alternating PbSe– and Bi 2 Se 3 –layer crystal structure is brought forth to recreate the mechanism of artificial superlattices and boost phonon localization. The thermal conductivity notably shows a direction–specific reduction, leading to minimum approaching and enhanced anisotropy. The modification of the natural framework and its effects have been supported by various transport and structure studies. This work sets a generalizable example for natural layered material engineering that bridges between the inflexible, changeless but self–assembled natural layered compounds, and the highly efficient, delicately tailored but unscalable artificial superlattice complexes. The methodology promises new horizons for practicable thermal management.
研究领域:
热物理
·
纳米制造
·
热电材料
✓ 已验证
DOI
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Hao Wang,Zixuan Yang,Yutong Gao,Ziyue Zheng,Jing Yang,Ting Wang,Dong Yang,Yajun Wang,Tongtao Li,Angang Dong
We present a coordination-inspired strategy for assembling binary nanocrystal superlattices (BNSLs) using CdSe nanotetrapods as symmetry-encoding building blocks. Exploiting their intrinsic tetrahedral geometry, which mimics the sp 3 hybridization of carbon atoms in a diamond lattice, we encode spatially defined binding sites that guide regioselective coassembly with spherical nanocrystals. By tuning the size ratio between components, we achieve both three-dimensional and two-dimensional BNSLs with long-range structural order. Notably, in NaCl-type BNSLs, the CdSe tetrapod sublattice defines a hypothetical porous network that is topologically analogous to a diamond lattice—an architecture difficult to realize using isotropic nanocrystals. The key advantage of this approach lies in its ability to translate molecular coordination principles into nanoscale assembly, thereby enabling access to architecturally complex and topologically rich lattices. A potential limitation, however, is the need for precise control over component size and shape to ensure high-quality ordering. By integrating molecular coordination concepts with nanocrystal assembly, this work establishes nanotetrapods as versatile symmetry-directing building blocks for the rational design of next-generation superlattices. This work establishes nanotetrapods as symmetry-directing building blocks for designing architecturally complex BNSLs, bridging molecular coordination chemistry with nanocrystal assembly.
研究领域:
材料科学
·
纳米技术
·
化学
·
凝聚态物理
·
自组装
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PHYSICA B-CONDENSED MATTER
·
2021
·
IF 2.436
Qilin Gong,Qingsong Huang
Recently, the moiré superlattice structure (MSS) has garnered increasing attention thanks to its extensive research potential in condensed matter physics . However, how to create MSSs on non-van der Waals crystal plates is still elusive. In the present study, we propose a new method to prepare MSSs on the MoO 2 (010) surface by soaking MoO 2 in sulfur vapour at high temperature. MoO 2 is 2D non-layered materials and is prepared by annealing MoO 3 with sulfur vapour at 500 °C. The torsional modulation between two stacked monolayers is periodic, which provides additional freedom to change the material properties . Under sulfur vapour, the surface atoms of MoO 2 first change from monoclinic to tetragonal crystals, and the interlayer covalent bonds are broken at the same time. Then, the top layer and buffer layer atoms of MoO 2 form the original MSS, and the top layer continue to rotate into different twisted angles. Our work provides some inspiration and reference to the preparation of MSSs on the surface of the other 2D non-van der Waals crystals. In addition, we further compared the wettability of MSS@MoO 2 and ordinary MoO 2 powder. The results show that the surface of MSS@MoO 2 is strongly hydrophobic (approximately 140°), while that of ordinary MoO 2 is superhydrophilic (4.3°). Our results suggest that MSSs may be a potential application to change the surface wettability of 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
NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 44
·期 48
·21112-21118
·
IF 3.288
Yangen Xie,Chunsheng Wang,Zhijie Yang,Huiying Wei,Jingjing Wei
Self-assembly of inorganic nanocrystals into ordered superlattices is of particular importance for their application in biomedicine and solid-state optoelectronic devices. However, dimensionality-controlled self-assembly of nanocrystals is still in its infancy. Emulsion-droplet confined self-assembly could offer a solution considering that the liquid/liquid interface and inner compartments can be respectively used as 2D and 3D templates for the assembly of nanocrystals, producing assemblies with a controlled dimensionality. CdSe nanorods with different aspect ratios were synthesized, and were applied as building blocks to uncover their assembly modes within the o/w emulsion droplets. The results reveal that by using both hydrophilic and lipophilic surfactants, hydrophobic CdSe nanorods can be locked at the liquid/liquid interface to produce a 2D supracrystalline sheet. In contrast, hydrophilic surfactants alone can result in the formation of 3D supracrystalline spherical colloids in similar conditions. Lipophilic surfactants, such as octylamine, can interact with the alkyl chains coated on the CdSe nanorods strongly, which consequently modulates the assembly mode of nanorods within the emulsion droplets. By considering the soft coatings of these supracrystalline structures with two different dimensionalities, these materials could be ideal candidates for the study of their interactions with biological soft matter.
研究领域:
材料科学
·
纳米技术
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 82
·66934-66939
·
IF 3.84
Yong Zhang,Fa-Min Liu
Bone-cuboid, spindle and rhombic TiO2 nanocrystals have been achieved by a simple solvothermal method with the oleic acid and oleylamine volume ratio at 5/5, 4/6 and 3/7, respectively. X-ray diffraction (XRD) and selected area electron diffraction (SAED) results show that all of the three shapes of TiO2 nanocrystals are highly crystallized anatase. Furthermore, for the first time, horizontal and vertical two-dimensional superlattices have been self-assembled with all three shapes of TiO2 nanocrystals by controlling the amount of TiO2 nanocrystals solution and oleic acid. The self-assembly process is primarily driven by maximization of the packing density and tuning entropic depletion attraction forces. In addition, the nanodots, nanorods and nanospheres of TiO2 nanocrystals have been obtained with various amounts of H2O2 (0 ml, 0.05 ml, and 0.25 ml). These ordered two-dimensional superlattices may be suitable for the fabrication of functional ultrathin films which take full advantage of the directional and shape-dependent properties for wide ranging devices.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Binbin Ding,Lianbi Li,Kaiwen Gong,Lei Li,Tianming Wang,Yaxian Yang,Changjun Zhu,Zebin Li,Guoqing Zhang,Dezhong Cao,Caijuan Xia,Wenzhi Yu
Stacking structures show great potential for the modulation of physical properties of two-dimensional materials. However, most studies have focused on bilayer (BL) stacking MoS 2 with same morphology. Here, we report a simple but effective process for manufacturing multilayer stacking MoS 2 crystal microstructures. The epitaxial growth mechanism is investigated by studying a typical trilayer (TL) stacking MoS 2 with different shapes. Raman and photoluminescence (PL) mapping exhibit high homogeneity and obvious boundary contrast between the different structures. The TL-MoS 2 microstructure field-effect transistor (FET) shows high carrier mobility and on/off ratio, which is related to stacking configuration. It is note that type I junction can form between the different structures and the obvious photocurrent observed are in the junction region. The 15.3° twisted BL-AB stacking MoS 2 Moiré superlattices with a period of 1.39 ± 0.05 nm. This work provides a reference for the development and application of multilayer-stacking MoS 2 .
研究领域:
材料科学
·
物理化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Min Liu,Teng Zhang,Yuanzheng Xia,Jiangpeng Zhou,Mengyu Liu,Yuxiang Zhang,Feiya Xu,Yiyan Cao,Chunmiao Zhang,Xuanli Zheng,Yaping Wu,Zhiming Wu,Xu Li,Junyong Kang
The bilayer (BL) transition metal dichalcogenides (TMDs), with their elevated carrier mobility and narrowed bandgap, are advantageous for future electronic applications in comparison with their monolayer (ML) counterparts. Here, we introduce a facile and efficient approach for the chemical vapor deposition synthesis of BL WS 2 . The method involves an acetic acid sonication treatment to modify the substrate surface morphology and the surface energy, which regulates the nucleation processes and shapes the growth mode of WS 2 crystals. Further modifications to the growth conditions yield high-quality ML and BL WS 2 films. A comparative study confirms the superior valley polarization and higher carrier mobility of BL WS 2 compared with its ML counterpart. Additionally, a minor twist angle existed between the upper and lower layers, featuring a Moiré superlattice. This work reveals the role of surface morphology and surface energy in the growth of TMDs. Simultaneously, it offers insights into the controlled preparation of vertically stacked homo- and heterojunctions.
研究领域:
材料科学
·
表面化学
·
电子器件
✓ 已验证
DOI
高影响因子
Materials Chemistry Frontiers
·
2021
·Vol. 5
·期 19
·7306-7314
·
IF 6.482
Xuejie Liu,Xuan Yue,Nan Yan,Wei Jiang
Three-dimensional (3D) superlattice materials self-assembled from functional inorganic nanoparticles (NPs) have attracted extensive attention due to the unique properties of the building blocks and additional intriguing collective properties derived from the interaction between adjacent NPs. However, the spontaneous assembly of inorganic NPs into 3D free-standing plasmonic superlattices still remains an enormous challenge. Herein, we report a facile and universal strategy to assemble gold nanoparticles (AuNPs) tethered with polystyrene (PS) and poly(2-vinylpyridine) (P2VP) homopolymers into 3D free-standing sheet-like superlattices by systematically tuning the oil/water interfacial tension and the interfacial instability of emulsion droplets. The prepared sheet-like superlattices are multilayer and the AuNP building blocks stack as tetrahedra, in which each AuNP building block is partially sitting on the three other nearby nanoparticles. Moreover, the interparticle distance between adjacent NPs can be effectively regulated by varying the molecular weight of the tethered PS ligands on the surface of AuNPs. This template-free approach provides a novel and effective route to manipulate nanoparticles into free-standing ordered 3D superlattices with a wide range of potential applications.
研究领域:
材料科学
·
纳米技术
✓ 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）