SEPARATION AND PURIFICATION TECHNOLOGY
·
2018
·
IF 3.927
Wenji Zheng,Rui Ding,Kai Yang,Yan Dai,Xiaoming Yan,Gaohong He
Poly (ether- block -amide) (Pebax) based mixed matrix membranes (MMMs) were prepared by using size-tunable ZIF-8 nanoparticles as fillers. ZIF-8 nanoparticles with sizes of 40, 60, 90 and 110 nm (ZIF-8-40, ZIF-8-60, ZIF-8-90 and ZIF-8-110) were synthesized in microemulsion by controlling the ratio of Zn 2+ to Hmim (1:16, 1:8, 1:5, 1:2). And they were distributed uniformly in Pebax matrix without obvious agglomerations and defects at the loading of 0–20 wt.%, which was confirmed by field-emission scanning electron microscopy (FE-SEM). The incorporation of ZIF-8 resulted in a significant improvement in CO 2 permeability and the CO 2 /N 2 selectivity increased with the BET surface area of ZIF-8 increasing. The enhanced permeability is attributed to an improvement in the free volume of the polymer induced by larger sized ZIF-8, while the increased selectivity results from the high specific surface area of large sized ZIF-8, which can provide more active sites for CO 2 capture and great mass transfer resistance for N 2 . At 5 wt.% loading of ZIF-8-90, the MMM presents the best separation performance with CO 2 permeability of 99.7 Barrer and CO 2 /N 2 selectivity of 59.6, both of which are increased by about 25% by comparison to the pure Pebax membrane. The present study provides an effective way to obtain size-controlled ZIF-8 fillers and high separation performances of Pebax based MMMs.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 60
·37823-37829
·
IF 3.108
Jinglei Liu,Yiqun Zheng,Shifeng Hou
We report a facile synthesis of copper/nickel (Cu/Ni) alloy nanospheres in high purity and with tunable, well-controlled sizes and elemental ratios. The success of this synthesis relies on the use of one-pot, direct thermal reduction of a Cu and Ni precursor mixture in the presence of trioctylphosphine (TOP) and oleylamine (OAm) at an elevated temperature to form Cu/Ni alloy nanoparticles with a spherical shape and uniform size. Their sizes could be readily tuned in the range of 6.9–27.3 nm by simply varying the volume of TOP added to the reaction solution. The elemental ratio of Cu to Ni in resultant products was found to remain the same as that in the precursor, which offers a simple way to manipulate the composition of Cu/Ni alloy nanospheres. We also tested the catalytic performance of as-prepared Cu/Ni alloy nanospheres and evaluate the effect of size and elemental ratio using the reduction of 4-nitrophenol as the model reaction. The current strategy enables the size and composition controlled synthesis of Cu/Ni alloy nanomaterials and could find important use in the fabrication of other types of bimetallic alloy nanomaterials with desired sizes and compositions for catalytic purposes.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 11
·2563
·
IF 3.1
Qi Liu,Hang Li,Xiaoqian Wang,Jiazhen He,Xuemin Luo,Mingwei Wang,Jinfeng Liu,Yong Liu
Amidst the rapid advancements in the fields of photovoltaics and optoelectronic devices, CsPbBr3nanosheets (NSs) have emerged as a focal point of research due to their exceptional optical and electronic properties. This work explores the application potential of CsPbBr3NSs in photonic and catalytic domains. Utilizing an optimized hot-injection method and a ZnBr2-assisted in situ passivation strategy, we successfully synthesized CsPbBr3NSs with controlled dimensions and optical characteristics. Comprehensive characterization revealed that the nucleation environment and thickness significantly influenced the structure and optical performance of the materials. The results indicate that the optimized synthesis method enables control over the lateral dimensions of the nanoparticles, ranging from 9.1 ± 0.06 nm to 334.5 ± 4.40 nm, facilitating the tuning of the excitation wavelength from 460 nm (blue) to 510 nm (green). Further analyses involving photoresponse and electrochemical impedance spectroscopy demonstrated the substantial potential of these NSs in applications such as photocatalysis and energy conversion.
研究领域:
材料科学
·
光化学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 23
·13201-13206
·
IF 3.049
Xu Yang,Maohui Yuan,Rui Wang,Xiaofan Zhao,Zining Yang,Kai Han,Hongyan Wang,Xiaojun Xu
Harnessing the color tuning capability of upconversion nanoparticles (UCNPs) is of great significance in the field of advanced bioimaging and color display. Here, we report the tunable size and upconversion luminescence (UCL) multicolor in CaF2:Yb3+/Ho3+/Ce3+ UCNPs, which were synthesized by a facile hydrothermal method. It was found that the size of these UCNPs could be controlled (from 600 to 30 nm) by varying the concentration of Ce3+ ions. Under the excitation of a 980 nm continuous-wave (CW) laser, the UCL color of these UCNPs can be tuned from green to red as the doped Ce3+ ions gradually increase from 0 to 10 mol% and the red-to-green (R/G) ratio is enhanced remarkably. It is suggested that the cross-relaxation (CR) processes between Ho3+ and Ce3+ ions contribute to the tunable multicolor and enhancement of the R/G ratio. The mechanism of these processes is well supported by the time-resolved decay and near infrared (NIR) emission measurements.
研究领域:
材料科学
·
生物成像
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2022
·Vol. 14
·期 42
·15804-15811
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IF 8.307
Qinzhen Li,Sha Yang,Jinsong Chai,Hui Zhang,Manzhou Zhu
Unraveling the rules governing the size regulation of nanoclusters is of great importance not only in fundamental research, but also in practical applications because of the high structure–property correlation in nanoclusters. Diphosphine-mediated size tailoring is recognized as a powerful method for modulating the size, configuration, and properties of nanoclusters, but the role of diphosphines in these size-controlled processes is still poorly understood due to a lack of systematic studies. Herein, using Au23(SR)16− as the template for modification, the factors influencing the size-modulation of nanoclusters by diphosphines were systematically investigated. It is revealed that by controlling the length of the diphosphines (from shorter to longer), Au21(SR)12L2+ (L = diphosphine) and Au22(SR)14L can be produced. Moreover, introducing a rigid group into the diphosphines can twist the structural framework or lead to the formation of a new surface motif configuration in the nanoclusters, forming twisted Au22(SR)14L and Au25(SR)16L2+. The size regulation of these nanoclusters enables fine-tuning of the optical properties, including the absorption wavelengths and photoluminescence emission intensity, affording an avenue for precise control of the physicochemical properties of nanoclusters for practical applications.
研究领域:
纳米材料科学
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配位化学
·
物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2016
·Vol. 52
·期 5
·2673-2683
·
IF 2.302
Huang Zhangyu,Yi Mengji,Gao Huiping,Zhang Zhenlong,Mao Yanli
A strategy is demonstrated for simultaneous size and color tuning of KZnF 3 :Yb 3+ /Er 3+ nanocrystals through transition metal Mn 2+ doping. The experimental results indicate that the introduction of Mn 2+ into the KZnF 3 :Yb 3+ /Er 3+ reaction system facilitates the decrease of the crystal size. Moreover, in the case of a high concentration of Mn 2+ doping, the downshifting (DS) and upconversion (UC) luminescence all show a single red band emission. In this work, we mainly investigate the DS and UC energy transfer process among Mn 2+ /Yb 3+ /Er 3+ in KZnF 3 nanocrystals by the detection and analysis of the absorption, excitation, emission, and transient fluorescence spectra. The results show that both Mn 2+ and Yb 3+ ions can decrease the green emission while improving the red luminescence of Er 3+ . This DS and UC single red color tuning is significant for the application of nanoparticles in light conversion, biological labeling, or plant photosynthesis.
研究领域:
材料科学
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光学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2021
·
IF 3.08
Rui Qu,Mingyang Gao,Haonan Li,Xiaofei Qi,Cheng Liu,Wu Zhao,Junfeng Yan,Zhiyong Zhang
Formamidinium lead bromide perovskite (FAPbBr 3 ) nanostructures have aroused increasing attention considering their excellent optoelectronic performance and higher stability than their MA- and Cs-based counterparts. Herein, we synthesized size-tunable FAPbBr 3 quantum dots (QDs) at room temperature. The size of the perovskite QDs could be ajusted from 5.4 to 2.3 nm by just varying the amount of Hydrobromic Acid (HBr) added into the precursor. As a result, the photoluminescence (PL) emissions exhibited large blueshift from 531 to 446 nm due to quantum confinement effect. Quantum mechanical calculations of the optical gap fitted well with the experimental results. We found that the addition of HBr not only increased the concentration of the Br − but also protonated the oleylamine ligands. The two events synergically governed the size-decreasing effect of the QDs with increasing amount of HBr. The size-tunable FAPbBr 3 QDs showed great application prospect in the field of photoelectric devices.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2019
·Vol. 11
·期 32
·15023-15028
·
IF 6.97
Chun Wu,Xiaoyang Wang,Wenli Pei,Dong Zhao,Kai Wang,Guojian Li,Qiang Wang
A 6 Tesla high magnetic field (HMF) was separately introduced into the nucleation stage and growth stage and into both stages during the wet-chemical synthesis of FePt nanoparticles. The HMF refined particle sizes and increased the nucleation rate in the nucleation stage and tailored shapes and refined sizes in the growth stage. Extension of nucleation time increased the nucleation rate more than that of the HMF, which increasing was higher enough to tailor the shapes of FePt nanoparticles. Controlling nucleation is a feasible strategy to tailor the shapes and sizes of wet-chemical synthesized nanoparticles.
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 Materials Chemistry C
·
2023
·Vol. 11
·期 38
·13030-13038
·
IF 6.4
Jie Chen,Yu Li,Zhe Yin,Shuaibing Wang,Ouyang Lin,Wentao Niu,Feng Teng,Aiwei Tang
Cu-based halide perovskites have attracted extensive attention in the optoelectronic field owing to their non-toxic nature and excellent stability. Nevertheless, the growth mechanism of Cu-based halide perovskite nanocrystals (NCs) remains unclear, and the size and uniformity of NCs are difficult to control, which seriously hinders the development of these materials. Herein, a facile hot-injection method was applied to control the size and uniformity of blue-emitting (450 nm) Cs3Cu2I5 NCs. The dimensions of Cu-based perovskites were tuned from zero-dimensional NCs to one-dimensional nanorods. Additionally, the sizes of Cs3Cu2I5 NCs could be tuned from 22.1 ± 1.5 to 8.9 ± 1.1 nm by varying the reaction temperature and the dosage of cesium oleate, which is also extended to tune the size of Cs3Cu2X5 (X = Br and Cl) NCs. Interestingly, the photoluminescence (PL) maximum at 450 nm was almost unchanged with the size tuning, indicating that PL is from the radiation recombination of self-trap exciton emission. Moreover, the phase transition temperature of Cs3Cu2X5 NCs was regulated by varying the size, where a small size is beneficial to the decrease of the phase transition temperature. As a demonstration, the different-sized Cs3Cu2X5 NCs exhibited a size-dependent temperature response, and the response time became shorter as the size decreased. The temperature response of the small-sized Cs3Cu2X5 NCs could be decreased to only 15 s, which is better than that of their counterparts reported previously. This work may deepen the understanding of the size-dependent phase transition process in Cu-based perovskite NCs.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Min Ji,Siqi Niu,Yunchen Du,Bo Song,Ping Xu
Molybdenum carbide materials are considered to be promising hydrogen evolution reaction (HER) electrocatalysts due to their similar electronic structures and catalytic activities to Pt-based catalysts. Here, we report a facile synthesis of β-Mo2C nanoparticles supported on nitrogen-doped carbon nanotubes (Mo2C/N–C) through a one-step carbonization of Mo-containing anion-doped polyaniline nanotubes. It has been revealed that the size of the obtained Mo2C nanoparticles can be effectively tuned by applying different Mo-containing anions. With MoO42– from Na2MoO4, the as-prepared Mo2C/N–C(S) with ultrasmall (2–3 nm) Mo2C nanoparticles shows excellent electrocatalytic HER activity in acidic media, with an overpotential of 189 mV vs reversible hydrogen electrode (RHE) at a geometric current density of −10 mA cm–2 and a Tafel slope of 58 mV dec–1. This study opens up a new avenue for the size-controllable synthesis of transition metal carbide nanoparticles loaded on carbon supports for energy conversion applications.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2016
·
IF 3.014
Lan Peng,Aiwei Tang,Chunhe Yang,Feng Teng
Size-tunable organometal halide perovskite CH 3 NH 3 PbBr 3 quantum dots (QDs) were successfully synthesized by a simple surfactant-assisted reprecipitation technique, in which the size-tunability was realized by varying the molar ratios of methylammonium bromide (CH 3 NH 3 Br) to PbBr 2 while the total amount of octylamine (OTAm) and CH 3 NH 3 Br remained unchanged. The diameters of CH 3 NH 3 PbBr 3 QDs could be effectively tuned from 1.6 to 3.9 nm, and these QDs exhibited an obviously size-dependent optical properties , whose photoluminescence (PL) covered the spectral region from 440 to 530 nm and the emission width was 20–32 nm. The maximum absolute PL quantum yield (PLQY) was measured to be as high as approximately 80% at room temperature. A plausible formation mechanism was proposed and the quantum confinement effect was discussed based on effective mass approximation. Moreover, this synthetic approach could also be extended to prepare different halide perovskite QDs including CH 3 NH 3 PbCl x Br 3 − x and CH 3 NH 3 PbBr 3 − x I x ( x = 1–3), which realized the color-tunability over the entire visible spectral region of 390–750 nm. The size- and compositional-tunable emission colors of organometal perovskite QDs endows them wide potential applications in next-generation optoelectronic devices.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2016
·Vol. 18
·期 31
·5940-5951
·
IF 3.849
Jingjing Cao,Li Yuan,Shanshan Hu,Jianfeng Tang,Xianju Zhou,Jun Yang
Monodisperse ScF3 and NaScF4 nano-/micro-crystals were prepared by a simple solvothermal method. There were many important factors including the molar ratio of Na/F/(Sc + Ln) and Ln3+ doping to control the synthesis of the products. A phase transformation from monoclinic ScF3 to hexagonal NaScF4 was observed with different molar ratios of Na/F/Sc. Herein, the products doped with 1% Ln3+ (La–Lu, except Pm) demonstrated abundant phases, morphologies and sizes. Moreover, the products with different Lu3+ doping concentrations from 1% to 60% were prepared. The results revealed that different kinds of 1% Ln3+ (La–Lu, except Pm) and diverse concentrations of Lu3+ can modify the phase, morphology and size of the prepared products. A possible formation mechanism for the products with diverse morphologies is proposed. In addition, Ln3+-doped ScF3 or NaScF4 nano-/micro-crystals presented characteristic up/down-conversion fluorescence spectra.
研究领域:
材料科学
·
化学
✓ 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）