LANGMUIR
·
2024
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IF 3.7
Weidong Fang,Zhi Tao,Haiwang Li,Yuqian Ma,Shuai Yin,Tiantong Xu,Teckneng Wong,Yi Huang
Emulsions have been applied in a number of industries such as pharmaceutics, cosmetics, and food, which are also of great scientific interest. Although aqueous emulsions are commonly used in our daily life, oil-in-oil (o/o) emulsions also play an irreplaceable role in view of their unique physics and complementary applications. In this paper, we investigate typical behaviors of organic droplets surrounded by organic medium (o/o emulsions) with different functional groups controlled by the AC electric field. Droplet behaviors can be catalogued into five types: namely, “no effect”, “movement”, “deformation”, “interface rupture”, and “disorder”. We identify the key dimensionless number Wee·Ca, combined with the channel geometry, for characterizing the typical behaviors in silicon oil/1,6-hexanediol diacrylate and mineral oil/1,6-hexanediol diacrylate emulsions. Unlike aqueous emulsion, the Maxwell–Wagner relaxation inhibits the electric effect and leads to an effective frequency, ranging from 0.5 to 3 kHz. The increasing viscosity of the droplet facilitates the escalation by promoting the shearing effect under the same flow conditions. Ethylene glycol droplets primarily show the efficient coalescence even at a low Wee·Ca, which is attributed to the attraction of free charges induced by the increasing conductivity. In 1,6-hexanediol diacrylate/silicon oil emulsion, the droplet tends to form a liquid film that expands into the entire channel due to the affinity of the droplet to the channel wall. A variety of elongated columns are observed to oscillate between the electrodes at high voltages. These findings can contribute to understanding the electrohydrodynamic physics in o/o emulsion and controlling droplet behaviors in a fast response, programmable, and high-throughput way. We expect that this droplet manipulation technology can be widely adopted in a broad range of chemical synthesis and biological and material science.
研究领域:
物理学
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化学工程
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2025
·
IF 19
Yu Su,Haitao Xie,Congzhou Li,Zhongjing Xia,Wenheng Xu,Zilong Mao,Guixiang Zhan,Kan Liao,Jiaqi Li,Jinze Li,Junran Zhang,Yao Yin,Lin Wang
2D Ruddlesden-Popper (RP) phase perovskites are promising materials for optoelectronic devices due to their unique properties and environmental stability. In this work, fully electrical, dynamic, and reversible modulation of photoluminescence (PL) intensity in RP-phase perovskite nanosheets at room temperature is achieved for the first time using alternating current (AC) electric fields. A capacitor structure with (PEA) 2 PbI 4 nanosheets and HfO 2 enables significant PL quenching, with the largest modulation amplitude reported to date. The degree of quenching depends on AC field parameters, including amplitude, frequency, waveform, and inter-electrode phase difference. Temperature-dependent measurements and impedance spectroscopy (IS) reveal that the PL quenching originates from an interfacial polarization field formed by AC-driven ionic displacement and directional accumulation, which perturbs exciton recombination. This work provides insights into ion migration and electric field interactions in 2D perovskites. It also establishes an energy-efficient method for tuning optoelectronic properties, offering a practical route for developing adaptive photonic systems and low-power, electrically tunable devices.
研究领域:
材料科学
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光学
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电子工程
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2025
·
IF 3.9
Yu Han,Wei Zhao
Induced-charge electro-osmosis (ICEO) is prevalent in electrochemistry and micro/nanofluidics, even when subjected to an alternating current (AC) electric field. Previous studies suggest that ICEO primarily occurs near electrodes or ion-selective membranes within a range of tens of microns. In this experimental study, we reveal the existence of additional modes in ICEO driven by an AC electric field. We demonstrate that nonlinear electroosmotic flow (EOF) can occur between two electrodes situated 5 mm apart through long-range electroconvection. Notably, we observe a soliton-like wave of ion concentration fluctuation traveling from the working electrode to the ground electrode, causing significant disruption to the electric triple layer (ETL) on the ground electrode. Consequently, both the ETL structure on the electrodes and the bulk fluid are profoundly influenced by an external electric field. These findings are vital for enhancing the understanding of intrinsic dynamics in electrochemical and energy systems and for the development of novel micro/nanofluidic devices.
研究领域:
微流控学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Hang Yang,Junfeng Wang,Dongbao Wang,Daorui Wang,Jian Gao,Bin Li
The regulation of particle-laden droplet behavior is crucial for interfacial heat and mass transfer in the liquid-liquid reaction systems. Accordingly, a clear understanding of droplet dynamic behaviors is of crucial importance. In this study, the behaviors of solid-particle-laden droplets in an immiscible dielectric liquid are experimentally investigated under the effect of a non-uniform AC electric field by high-speed imaging. The evolution processes of droplet formation, coalescence, dispersion as well as liquid bridge are analyzed systematically in variable applied voltages and particle concentrations. Results show that the droplet formation process are accelerated by increasing particle concentration, producing smaller droplets. When the applied voltage exceeds a certain threshold, the charged droplet coalescence occurs while the presence of particles would reduce this critical voltage. Cascade coalescence happens in the pure system with increasing voltage while the particle-laden droplets tend to coalesce individually. The droplet dispersion is found to dominate at high electric field strengths with its oscillation angle increased by particle concentration. Additionally, the liquid bridge expansion is reduced by the addition of particles, hindering the droplet coalescence. These findings provide insights into the regulation of particle-laden droplet behavior under the effect of electric fields.
研究领域:
流体力学
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电液动力学
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多相流
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化学工程
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胶体与界面科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2025
·
IF 9
Ping-Jui Su,Yi-Hua Lin,Chih-Chia Cheng,Chien-Hsing Lu,Jem-Kun Chen
Branched polyethyleneimines (bPEI) were dual-crosslinked with 1,4-butanediol diglycidyl ether and tetrakis(hydroxymethyl)phosphonium chloride to form the molecularly imprinted (MIP) layer for bilirubin. Core/shell-structured membranes (PEO/MIP) with bilirubin-philic cavities were obtained using coaxial electrospinning. Electric polarization (EP) induced the separation of positive and negative charges in the membranes, thereby improving adsorption efficiency. The PEO/MIP was placed between two steel meshes to generate an alternating current electric field (ACEF) during bilirubin adsorption. The maximum adsorption capacity of bilirubin on PEO/MIP increased significantly from 136.99 to 208.33 mg/g when the membranes were subjected to an ACEF at 150 kHz and 2.5 V. The adsorption rate constant of bilirubin on PEO/MIP was also enhanced under EP. Due to the dynamic electrostatic force, the imprinting factor of PEO/MIP in the presence of ACEF was 25 % higher than that in its absence. At 1200 kHz, however, the maximum adsorption capacity of bilirubin on PEO/MIP decreased to 39.4 mg/g because of energy dissipation, which facilitated desorption from the recognition sites. The PEO/MIP could be reused 12 times under polarization switching frequencies ranging from 150 to 1200 kHz, exhibiting low damage and high stability. These results demonstrate that ACEF frequency can manipulate the adsorption behavior of bilirubin, enabling both enhanced bilirubin adsorption and efficient reuse of PEO/MIP.
研究领域:
生物医学工程
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高分子科学
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纳米技术
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膜技术
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生物分离
✓ 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）