CRYSTENGCOMM
·
2019
·Vol. 21
·期 38
·5749-5756
·
IF 3.382
Wen Zeng,Haojie Lai,Tianyin Chen,Yueheng Lu,Zhihong Liang,Tingting Shi,Ke Chen,Pengyi Liu,Fangyan Xie,Jian Chen,Jianbin Xu,Qiulan Chen,Weiguang Xie
VO2 particles with a reduced size enable the optimization of its metal–insulator transition (MIT) temperature and hysteresis width. The accurate modulation of particle size and the underlying mechanism of transition behavior remains a critical issue. In this study, the annealing process of a V2O5 precursor film was systematically controlled with the guidance of the V–O phase diagram. The film undergoes a synergistic solid-state dewetting and pyrolysis process in the first step to form dispersed VO2 particles, and then a crystallization process to achieve the preferred orientation, which allows fine control of the particle size and crystallinity by thickness control of the precursor film. Then, the MIT behavior of VO2 particles with controlled sizes from 220 nm to 1.64 μm was systematically investigated. With decreasing size, the MIT temperature decreases and then increases with enlarged hysteresis. A minimum MIT temperature of 41 °C without hysteresis was realized. Size dependent crystallinity, strain and defect analyses showed that compressive stress dominates the MIT behavior of larger sized particles, while surface tensile stress and surface defect effects become prominent in smaller sized particles. This work provides a feasible strategy to control the size effect of dispersed VO2 particle films and deepen our understanding on the MIT behavior in single domains.
研究领域:
材料科学
·
凝聚态物理
·
纳米科技
✓ 已验证
DOI
高影响因子
Nano-Micro Letters
·
2021
·Vol. 13
·期 1
·1-13
·
IF 16.419
Qu Danyao,Jian Yingying,Guo Lihao,Su Chen,Tang Ning,Zhang Xingmao,Hu Wenwen,Wang Zheng,Zhao Zhenhuan,Zhong Peng,Li Peipei,Du Tao,Haick Hossam,Wu Weiwei
An organic solvent-assisted intercalation and collection (OAIC) approach for preparing Ti 3 C 2 T x (MXene) was developed.
The features of OAIC approach are the low requirement for facility, gram-level preparation with remarkable yield and easy control over the dimension of Ti 3 C 2 T x flakes.
The Ti 3 C 2 T x flakes prepared by OAIC approach showed the outstanding capacitive and rate performance.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2016
·Vol. 16
·期 1
·480-488
·
IF 1.338
Kaili Zhang,Yongguo Du,Shimin Chen
This study reports the development of a facile and efficient one-pot polyol method for the synthesis of silver nanowires. The seed and growth of silver nanowires under different reaction conditions were characterized and measured. The pertinent variables such as temperature, time, concentration
and capping agent were investigated. Moreover, the effect of seeding at two different stages—initial stage and secondary stage–was studied and discussed on the size control of silver nanowires. In particular, silver nanowires with diameter less than 40 nm and length over 25 μm
in a narrow distribution, was obtained through a novel method in which reaction flask was placed in a lowtemperature bath after seeding for some time in the high-temperature bath. This approach may be useful for the fabrication of uniform, large aspect ratio silver nanowires for optoelectronic
applications.
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2014
·Vol. 181
·期 11
·1393-1399
·
IF 3.719
Jiao Hangzhou,Zhang Ling,Liang Zhenhua,Peng Guihua,Lin Hengwei
We have synthesized water dispersible CdTe quantum dots (QDs) in different sizes and with various capping reagents, and have studied the effects of their size on the sensitivity and selectivity in the fluorometric determination of metal ions, particularly of silver(I). It is found that an increase in the particle size of homocysteine-capped CdTe QDs from 1.7 nm to 3.3 nm and to 3.7 nm enhances both the sensitivity and selectivity of the determination of Ag(I) to give an ultimate limit of detection as low as 8.3 nM. This effect can partially be explained by the better passivation of surface traps on smaller sized QDs via adsorption of Ag(I), thereby decreasing the apparent detection efficiency. In addition, the presence of CdS in the CdTe QDs is likely to play a role. The study demonstrates that an improvement in sensing performance is accomplished by using QDs of fine-tuned particle sizes. Such effects are likely also to occur with other QD-based optical probes.
Improvement of sensing performance by the use of quantum dots based fluorescent probes can be achieved through tuning their particle sizes and should be considered as an important factor in developing relevant probes.
研究领域:
分析化学
·
纳米生物学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Huigang Du,Kaiyang Wang,Lidan Zhao,Chang Xue,Mengying Zhang,Weijia Wen,Guichuan Xing,Jinbo Wu
Single-crystalline halide perovskites with regular morphology are of great significance for laser applications because they can be used to fabricate a natural whispering-gallery-mode resonator. Although enormous efforts have been put to synthesize single-crystalline perovskites, controlling the lateral size and thickness of the crystal, particularly at the nanoscale, is still challenging. Here, we report a facile and high-throughput strategy to selectively one-step create micro/nanoscale size-controlled all-inorganic perovskite single-crystal arrays by surface-tension-confined evaporative assembly. Our method can be used to easily tune the single crystal size and selectively position the single crystal, with versatility in fabricating perovskite single-crystal arrays in a wafer scale. When the patterned size increases from 2 to 25 μm, the width of the CsPbClBr2 perovskite microplates increased from 150 nm to 4.2 μm. Fixing the width of the microplates at 1.6 μm, with the increase of the sliding speed from 50 to 250 mm/min, we could significantly control the thicknesses from 270 to 430 nm. Additionally, our present study provides a characterization of lasers based on different three-dimensional structures, confirming their width-dependent lasing mode and thickness-dependent lasing threshold characteristic, which is beneficial for the tunability of a high-performance microlaser.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Mingshuo Tian,Zhiwei Huang,Jiangwei Ni,Wen Chen,Qiqi Zhou,Huazhen Shen,Xiaomin Wu,Huawang Zhao,Guohua Jing
The elucidation of active sites in Pt-based catalysts for benzene combustion has been a long-standing challenge, hindering the rational design of such catalysts. We have successfully pinpointed the active sites to the perimeters of Pt nanoparticles, deliberately excluding corner atoms. This achievement stems from a comprehensive approach, encompassing controlled synthesis of Pt nanocrystal size and morphology, advanced spectroscopic characterization, and detailed geometrical model analysis. We synthesized well-defined truncated hexahedral Pt nanoparticles with diameters (d) ranging from 2.2 to 6.6 nm. Notably, the turnover frequency (TOF) of our Pt/TiO 2 catalyst correlates inversely with the nanoparticle diameter, following a d -1.09±0.11 trend. This correlation matches the model-predicted perimeter-to-diameter ratio (excluding corners) with a d -1.01±0.09 exponent, confirming the location of the active sites. Further support comes from X-ray photoelectron spectroscopy and experiments using different support materials, which underscore the high activity at the Pt/TiO 2 interface. A crucial H 2 treatment step encapsulating the Pt nanoparticles by TiO x excludes both surface areas and corners as contributing active sites. The 0.7 % Pt/TiO 2 catalyst also demonstrated remarkable stability under testing conditions. In situ FTIR analysis provided insight into the stepwise mechanism of benzene combustion, revealing intermediate species and their transformation pathways. By finely tuning the geometry of Pt nanoparticles and correlating TOF with specific surface sites, our research highlights the perimeters of Pt atoms as the prime active sites for benzene combustion. These results contribute significantly to the field, offering a strategic approach to designing efficient catalysts for VOC elimination, with implications for both environmental protection and the advancement of catalytic science.
研究领域:
催化科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
LAB ON A CHIP
·
2018
·Vol. 18
·期 18
·2806-2815
·
IF 5.995
Liping Mei,Mingliang Jin,Shuting Xie,Zhibin Yan,Xin Wang,Guofu Zhou,Albert van den Berg,Lingling Shui
We report an easily-established capillary-based open microfluidic device (COMD) as a simple and robust method for size on-demand generation of monodisperse droplets of various fluidic materials with controllable volume. A device is set up in which a capillary is positioned with its tip close to a flat surface with a precise gap distance in a container. The continuous phase remains static in the container, and the dispersed phase is pumped through the capillary and forms droplets at the exit of the gap. Monodisperse droplets, bubbles and microcapsules of various fluids with diameters of 10–300 μm (picoliter to nanoliter) and generation frequency of 1–1000 Hz are obtained by controlling the gap distance in the range of 5–500 μm. The droplet formation is caused by capillarity-induced narrowing of the dispersed phase at the capillary exit, with droplet size being determined by the gap volume and fluid flow. We find that, at low flow rate, using the same COMD, the generated droplet size is constant, being determined by the gap size; however, at higher flow rate, droplet size increases with the flow rate. Droplet types can be managed by fluids and surface modification of the capillary and bottom surfaces. High throughput droplet generation is achieved by in-parallel integration of multiple capillaries in one device. Such a COMD is simple and easy-to-build without complex microfabrication requirements; however, it is highly robust, flexible and easy-to-operate for size on-demand droplet generation. It offers an opportunity for common laboratories to perform droplet-based assays, and has high potential for high throughput industrial emulsification applications as well.
研究领域:
生物工程
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FIBERS AND POLYMERS
·
2018
·Vol. 19
·期 5
·927-933
·
IF 1.353
Maimaiti Yuemaierjiang,Dongmulati Naziermu,Baikeri Salamaiti,Maimaiti Abulajiang,Maitisidike Rukeya,Maimaitiyiming Xieraili
A process for controlling the size of Single-walled carbon nanotubes (SWCNTs) sorting was achieved by combining various centrifugation speeds with polypyrimidine’s properties of dispersion and release SWCNTs upon acid treatment. At first, the SWCNTs wrapped by polypyrimidine were sperated into different size by centrifugating at various speeds. Then, these size-selected hybrids were treated with H 2 SO 4 (98 %) to release free SWCNTs from hybrids, meanwhile the copolymer was collected for reuse. The purity of the released size-controlled SWCNTs was found to be higher than the commercial SWCNTs. The simple synthetic procedure of the copolymer, the low cost of H 2 SO 4 and low centrifugation speed allow the process of size-controlled SWCNTs sorting to more practical applications and industrial scaling up.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Crystals
·
2018
·Vol. 8
·期 10
·367
·
IF 2.144
Fang Fu,Bin Zheng,Lin-Hua Xie,Huiling Du,Shuangming Du,Zhenhua Dong
Composite materials that combine the unique properties of zeolitic imidazolate frameworks (ZIFs) and carbon nanotubes (CNTs) can give rise to novel applications. Here, ZIF-8/CNT composites were successfully prepared with and without the addition of an agent template. The size of the ZIF-8 crystals in the composite materials was controlled by varying the template, feeding order, and concentration of reactants. Thus, ZIF-8 crystals with a wide variety of sizes (from nano- to micrometer size, which is range that differs by a factor of 10) were obtained, depending on the conditions. This size-controllable synthesis of ZIF-8 was achieved by modifying the number of nucleation sites on the CNTs, as revealed by density functional theory (DFT) calculations. This work provides an efficient method for preparing ZIF-8/CNT composites with controllable size and can pave the way for the synthesis of other metal-organic framework (MOF)/CNT composite materials.Keywords:crystal growth;ZIF-8;carbon nanotube;DFT calculation
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2017
·Vol. 19
·期 44
·6588-6593
·
IF 3.474
Yu Han,Wenxing Wang,Penglin Jiang,Yucong Yan,Hui Zhang,Deren Yang
Au nanorings are of particular interest in catalysis owing to their fascinating properties, however, it still remains a tremendous challenge to generate such hollow nanostructures with small size. Here, we report the synthesis of Au nanorings with an outer diameter of less than 20 nm by a seed-mediated approach with Pd nanoplates as seeds in the presence of Ag+ ions. The incorporation of Ag+ ions substantially slows down the reduction rate of the Au precursor through an underpotential deposition (UPD) process, leading to the formation of small Au nanoparticles. These small Au nanoparticles then coalesced into nanorings on small Pd nanoplates. The outer diameter of the Au nanorings is tuned by varying the size of the Pd nanoplates. The smallest Au nanorings are evaluated as catalysts towards the hydrogenation of 4-nitrophenol, showing substantially enhanced catalytic activity relative to the Au nanoparticles with the same size. This enhancement in the catalytic activity can be attributed to the unique structural features including the large specific surface areas, convenient accessibility of both interior and exterior surfaces for the reactants, and existence of highly active sites in the interior part.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2023
·
IF 4.5
Jun Gu,Guolang Zhou,Linlin Chen,Xiaowei Li,Guiling Luo,Linjing Fan,Yanhong Chao,Haiyan Ji,Wenshuai Zhu
With the unprecedented heat of lithium resources, it has been a hot topic to find an effective, low-energy-consumption, and eco-friendly method for extracting lithium from salt lakes. As an electrochemically active material, LiMn 2 O 4 (LMO) is widely used in electrochemical lithium extraction. In order to reduce the Mn dissolution loss and improve the cycle stability of LMO, we designed octahedral LMO with controllable particle size by adjusting the water/ethanol volume ratio of the precursor solution. Through the electrochemical performance test, it was found that with the increase in particle size, the cycle stability of LMO and the lithium ion transport performance also improved. The Mn dissolution loss per 30 cycles of LMO (B-LMO) was 0.187%, and the capacity was maintained at the initial 86.9%. The electrochemical lithium extraction system of B-LMO//Ag exhibits excellent lithium extraction performance. After 1 h of extraction, the lithium extraction capacity is 20.6 mg/g, and the energy consumption is 15.2 Wh/mol.
研究领域:
材料科学
·
电化学工程
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Saiyu Yang,Zicheng Yin,Xianchun Chen,Zhide Geng,Bo Wang,Junwen Zhou,Lu Wang
Conventional methods for synthesizing nano-sized metal-organic frameworks (nano-MOFs) often rely on additives or extra conditions, overlooking the critical role of solvents. Here, we highlight tetramethylene sulfone (TMS, or sulfolane) as a versatile solvent for nano-MOF synthesis. TMS forms strong solvation structures with metal ions and inhibits ligand deprotonation, enabling control over particle size. Using TMS, we synthesized ZIF-65 [Zn(2-nIm)2, 2-nIm = 2-nitroimidazole], ZIF-8 [Zn(2-mIm)2, 2-mIm = 2-methylimidazole], UiO-66 [Zr6O4(OH)4(BDC)6, BDC = 1,4-dicarboxybenzene acid], and MOF-199 [Cu3(BTC)2, BTC = 1,3,5-benzenetricarboxylic acid] with significantly smaller particle sizes compared to traditional solvents like ethanol (EtOH). Systematic analysis on the growth of ZIF-65 revealed distinct growth behaviors: in TMS, slower kinetics allowed the coexistence of nucleation and growth over an extended period, leading to an increase in particle number while maintaining relatively constant size; in contrast, EtOH promoted rapid growth followed by Ostwald ripening, resulting in larger particles and reduced particle number over time. By adjusting reactant concentration, metal-to-ligand ratio, and reaction temperature, we achieved facile size modulation of ZIF-65 nanoparticles. This work underscores the importance of solvents in nano-MOF synthesis and offers a robust strategy for tailoring MOF particle size, advancing applications in catalysis, biomedicine, and beyond.
研究领域:
材料科学
·
化学工程
·
纳米技术
✓ 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）