Nanoscale Research Letters
·
2012
·Vol. 7
·期 1
·1-6
·
IF 2.726
Sun Li,Luan Weiling,Shan Yue Jin
A capillary micro-reaction was established for the synthesis of Au-Ag alloy nanoparticles (NPs) with a flexible and controllable composition and grain size by tuning the synthesis temperature, the residence time, or the mole ratio of Au 3+ :Ag + . By extending the residence time from 5 to 900 s, enhancing the temperature from 120°C to 160°C, or decreasing the mole ratio of Au 3+ :Ag + from 1:1 to 1:20, the composition of samples was changed continuously from Au-rich to Ag-rich. The particles became large with the increase of the residence time; however, synthesis temperatures showed less effect on the particle size change. The particle size of the Au-Ag alloy NPs with various composition could be kept by adjusting the mole ratio of Au 3+ :Ag + . TEM observation displayed that the as-obtained NPs were sphere-like with the smallest average size of 4.0 nm, which is half of those obtained by the traditional flask method.
研究领域:
材料科学
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纳米技术
✓ 已验证
DOI
高影响因子
Materials
·
2019
·Vol. 12
·期 12
·1883
·
IF 2.972
Zhuhua Xu,Yanfei Lv,Feng Huang,Cong Zhao,Shichao Zhao,Guodan Wei
Monolayer tungsten disulfide (2D WS2) films have attracted tremendous interest due to their unique electronic and optoelectronic properties. However, the controlled growth of monolayer WS2is still challenging. In this paper, we report a novel method to grow WS2through chemical vapor deposition (CVD) with ZnO crystalline whisker as a growth promoter, where partially evaporated WS2reacts with ZnO to form ZnWO4by-product. As a result, a depletion region of W atoms and S-rich region is formed which is favorable for subsequent monolayer growth of WS2, selectively positioned on the silicon oxide substrate after the CVD growth.Keywords:monolayer WS2;ZnO;CVD;controlled growth
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
JOURNAL OF NANOPARTICLE RESEARCH
·
2013
·Vol. 15
·期 9
·1-7
·
IF 2.175
Zong Kai,Lu SiHeng,Wang Hao,Sun YuXiu,Liu JingBing,Yan Hui
Cu 2 ZnSnSe 4 quantum dots (QDs) with controllable sizes have been synthesized via a hot-injection method. The diameters of the QDs range from 3.2 to 10.1 nm with the tunable band gap from 1.27 to 1.54 eV by adjusting the reaction temperatures from 180 to 240 °C. Structural and Raman scattering data confirm that Cu 2 ZnSnSe 4 is obtained without other secondary phases. The band gaps of the QDs with diameters less than 4.6 nm show an obvious blue shift to higher energy due to quantum confinement effect. It indicates that the Cu 2 ZnSnSe 4 QDs can be a potential candidate for quantum-dot-sensitized solar cells in the future.
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
DRUG DEVELOPMENT AND INDUSTRIAL PHARMACY
·
2015
·
IF 2.101
Jianmin Chen,Yuqin Qiu,Suohui Zhang,Guozhong Yang,Yunhua Gao
Coated microneedles have been paid much attention recently, and several coating strategies have been developed to address the problems during coating process. However, there are still some unresolved issues, such as, precise control requirements, microneedle substrate contamination and high processing temperature. The purpose of this study was to develop a simple and controllable method to make uniform coatings on microneedles at room temperature. This novel method avoids the contamination of microneedle substrate by providing both the adsorption force of thickener and micro-scale coating film produced by a newly design device. Thickeners were screened to enhance the mass of coatings. The parameters that influence the coatings were tested systematically, which made coating process controllable. Finally, three model drugs were coated onto microneedles to prove the method is applicable more broadly. In addition, insertion experiments were carried out to test the drug delivery feasibility of the coated microneedles. In conclusion, this study presents a simple and controllable method to coat microneedles with small molecular chemical drugs or large proteins for rapid skin drug delivery.
研究领域:
药剂学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nano Energy
·
2024
·
IF 16.8
Zhongrong Chen,Yulin Lai,Siyu Xu,Mengfei Zhu,Yue Sun,Yue Cheng,Gang Zhao
Hypertensive emergency is a clinical syndrome characterized by abrupt and substantial elevation of blood pressure in hypertensive patients due to specific triggers, leading to potentially life-threatening consequences. Intravenous injection of sodium nitroprusside is commonly used to rapidly lower blood pressure. However, its specialized nature limits its applicability for first aid or self-help in emergency situations. To address this issue, we have developed a self-powered and controllable microneedle drug delivery system that is easy to use and effective for lowering blood pressure. The system mainly consists of two parts: a piezoelectric thin film self-powered module made of polyvinylidene fluoride and carbon nanotubes, and a drug delivery module composed of polylactic acid-Au microneedles and polylactic acid-Au-polypyrrole microneedles. The results show that different pressures applied to the self-powered module generate different voltages, thereby controlling the drug release efficiency of the microneedles. Compared with conventional active devices, it exhibits a higher drug release rate and effectiveness. Furthermore, the system was successfully utilized to reduce and control blood pressure in spontaneously hypertensive rats. Compared with the injection of sodium nitroprusside, this system can more effectively lower and control blood pressure levels, and its biological safety has been verified. This study presents a controllable and user-friendly rapid blood pressure lowering system suitable for hypertensive emergencies, which has important clinical application prospects.
研究领域:
医学工程
·
药理学
·
生物医学材料
✓ 已验证
产品关联
DOI
高影响因子
Advanced Materials Technologies
·
2021
·Vol. 6
·期 8
·2100004
·
IF 7.848
Xiaocheng Hu,Yimou Fu,Yide Liu,Binhong Liu,Shaoxing Qu
Adhesion appears in nature as a kind of clinging strategy for living creatures to survive in a complex environment. Nevertheless, the artificial counterpart applications are limited by many factors, such as slow responding rate and high driving voltage. In this paper, a novel magnetic adhesion achieved by the actuation of Ecoflex embedded with iron particles is presented, which is demonstrated by a magnetic suction cup (MSC) that can switch the adhesion state within 500 ms. Compared with suction cups made of the dielectric elastomer in existing literature, the present work's driving voltage is safe for humans. Furthermore, a mechanical model is developed and verified to optimize the design of the MSCs. By applying an altering magnetic field, the adhesive force varying with time exhibits complex waveforms such as sinusoidal wave, triangle wave, square wave, and even pulse wave can be achieved. For some situations that large adhesion force is not necessarily considered while the adhesion requires to be accurately and quickly controlled, such as transfer printing and intelligent sensing, the magnetic adhesion demonstrated in this article will enrich the future available applications.
研究领域:
仿生学
·
材料科学
·
机器人学
✓ 已验证
DOI
高影响因子
Nano Research
·
2020
·Vol. 13
·期 11
·2933-2938
·
IF 8.183
Gao Xiang,Xiong Liukang,Wu Jiabin,Wan Jun,Huang Liang
Two-dimensional molybdenum disulfide (2D MoS 2 ) is considered as a promising candidate for many applications due to its unique structure and properties. However, the controllable synthesis of large-scale and high-quality 2D 1T-phase MoS 2 is still a challenge. Herein, we present the scalable and controllable synthesis of 2D MoS 2 from 2H to 1T@2H phase by using K 2 SO 4 salt as a simultaneous high-temperature sulfur source and template. The as-synthesized 1T@2H-2D MoS 2 exhibits a high yield and can be easily assembled into freestanding electrode with high specific capacitance of 434 F/g at a scan rate of 1 mV/s in LiClO 4 ethylene carbonate/dimethyl carbonate (EC/DMC). Moreover, various single-crystal 2D transition metal sulfides (WS 2 , PbS, MnS and Ni 9 S 8 ) and 2D S-doped carbon can be synthesized using this method. We believe that this study may provide a new sight for scalable and controllable synthesis of other 2D materials beyond 2D MoS 2 .
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Materials Science and Engineering B-Advanced Functional Solid-State Materials
·
2022
·
IF 3.407
Peng Chen,Xin Shan,Xin Lin,Heyan Yuan,Yangyang Xie,Fang Wang,Kailiang Zhang
Bi 2 O 2 Se has attracted a lot of attention in the field of photodetection due to its ultra-high mobility and tunable band gap. However, the mechanism of controllable preparation of high-quality Bi 2 O 2 Se is unclear and needs further investigation. In this paper, the concentration of reactants in the substrate region was increased by the method of space-compression, the number of nucleation was effectively controlled, and larger size Bi 2 O 2 Se was obtained. And the nucleation and selenylation mechanisms of Bi 2 O 3 were revealed based on the effect of temperatures modificatives growth of Bi 2 O 2 Se. And the controlled growth was achieved in a certain thickness range by increasing the reactant concentration in the substrate region and controlling the nucleation number. Moreover, photodetectors were constructed based on the highly crystalline Bi 2 O 2 Se. The photodetector exhibited a photoresponsivity of up to 9550 A/W under the excitation of 405 nm light and obtained highly stable and recoverable characteristics with multiple laser switches.
研究领域:
材料科学
·
光电技术
✓ 已验证
DOI
高影响因子
RSC Advances
·
2021
·Vol. 11
·期 50
·31226-31234
·
IF 3.361
Dapeng Li,Peng Zhang,Suxiang Ge,Guofu Sun,Qin He,Wenjun Fa,Yun Li,Juntao Ma
Exploring the environmentally friendly and low-cost synthesis strategies of phthalocyanine (Pc) crystals in just one step is an absolute challenge. The solvothermal synthesis of phthalocyanine crystals shows the advantages of high-quality crystalline products, facile reaction and purification, and low cost. Nevertheless, only a few metal phthalocyanine crystals have been successfully synthesized via solvothermal reactions. In this study, we found that the crystalline β metal-free phthalocyanine needles could be directly prepared via the tetrapolymerization of phthalodinitrile catalyzed by DBU in solvothermal reactions. Similar to the preparation of β-phthalocyanine crystals, the α metal-free phthalocyanine crystals with the specific multiply-laminated structures can be obtained through solvothermal reactions assisted by DBN. SEM characterization showed that the individual β metal-free phthalocyanine has a well-defined quadrangular shape with smooth faces. However, the α metal-free phthalocyanine exhibits a distinctive undulating surface morphology. Both phthalocyanines showed satisfactory thermal stability (from room temperature to about 300 °C), excellent resistance to acid/alkali solution, and fast photoelectric response properties (order of magnitude of response time, 10−6 s) as tested by TG-DSC and TPV, respectively. It is noted that ethanol was used as the reaction medium and the resulting phthalocyanine crystals can be facilely purified using hot ethanol to dissolve the impurities adsorbed on the surfaces of phthalocyanine crystals. Compared to the traditional methods, no re-crystallization operation was carried out for our method. To the best of our knowledge, this is the first report on the solvothermal synthesis of metal-free phthalocyanine crystals with controllable crystal form adjusted by DBU/DBN in one step.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2018
·Vol. 8
·期 12
·1015
·
IF 3.504
Liangfeng Zhang,Simin Liu,Yuhua Wang,Haijun Zhang,Feng Liang
A series of gold nanoparticles (AuNPs) was prepared in situ with different cucurbit[n]urils (CB[n]s) in an alkaline aqueous solution. The nanoparticle sizes can be well controlled by CB[n]s (n=5,6,7,8) with different ring sizes. The packing densities of CB[5–8] and free surface area on AuNPs were determined. A direct relationship was found between the ring size and packing density of CB[n]s with respect to the AuNP-catalyzed reduction of 4-nitrophenol in the presence of NaBH4. The larger particle size and higher surface coverage of bigger CB[n]-capped AuNPs significantly decreased the catalytic activity. Furthermore, this work could lead to new applications that utilize AuNPs under an overlayer of CB[n]s for catalysis, sensing, and drug delivery.Keywords:gold nanoparticles;cucurbit[n]urils;controllable synthesis;catalysis
研究领域:
化学
·
材料科学
·
催化
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Hui-Min Zeng,Mengyuan Cheng,Weimin Xuan,Yongge Wei
Cyclic compounds are appealing owing to their intrinsic porous structures and facile accessibility as building blocks (BBs) for fabricating high-order assemblies. Nevertheless, the modular synthesis of such molecular entities and their subsequent controlled assembly are still very challenging. Herein, we report the synthesis of a gigantic molybdenum blue (MB) wheel {Mo158} (1), featuring a skirt-shaped structure dimerized from {Mo79}. {Mo79} exhibits an unprecedented octameric architecture built from eight sets of {Mo8} BBs, and the controlled assembly of this smallest member in the MB library is achieved by proper wheel contraction induced by {Mo1} and edge-sharing {Mo2} BBs. Moreover, {Mo158} can function as a 4-connected giant synthon, connecting with adjacent four clusters in a controlled manner via four Mo–O–Mo bridges, resulting in a high-order architecture with a 2D layer structure. In addition to single-crystal X-ray diffraction, {Mo158} is fully characterized by a variety of spectroscopies, allowing for the unambiguous determination of its structure and formula. This work not only enriches the family of gigantic clusters but also demonstrates their potential for constructing more complex assemblies.
研究领域:
无机化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Fenglong Li,Zifa Xu,Han Hu,Zhengyang Kong,Chao Chen,Ying Tian,Wenwu Zhang,Wu Bin Ying,Ruoyu Zhang,Jin Zhu
Two of the very important demands for the elastic matrix of electronic skin (E-skin) are durability and degradability, which ensure the stable performance in daily life and green end of the E-skin. Unfortunately, these two requirements are usually incompatible. Here, we proposed the idea of controlled degradation and synthesized a polyurethane, AL-PU-4, to solve such challenge. High crystalline hydroxy-terminated poly (1,4-butylene adipate) (HTPBA) and low crystalline polycaprolactone diol (PCL diol) were mixed and used as the degradable soft segment. The dynamic disulfide bond was chosen as the chain extender, which could simultaneously endow the polyurethane with anti-aging and self-healing properties. The AL-PU-4 didn’t show significant loss in mechanical and molecular weight after 12 days of accelerated aging experiment, which equaled to 12 months of daily use, and it owned a fast room temperature self-healing speed of 1.31 μm/min. With the steric protection of the hard segment, the degradation of ester bonds in HTPBA and PCL diol segments was seriously retarded under enzymatic and low pH conditions. Only when the pH reached 14, the ‘lock’ on degradation was opened. The above functionalities were also verified in an E-skin demo, which could response the external pressure quickly and show high stability in cyclic test.
研究领域:
材料科学
·
生物医学工程
✓ 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）