INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2021
·
IF 3.764
Wei Si,Qingqing Yang,Yuan Zong,Guobin Ren,Ling Zhao,Minghuang Hong,Zhong Xin
During the fabrication of poly(lactide-co-glycolic acid) (PLGA) microspheres by the water/oil/water (W1/O/W2) emulsion solvent evaporation method, water permeation coupled with dichloromethane (DCM) volatilization represents a critical process affecting the microsphere morphology. In this work, the mechanism of pore formation in PLGA through water permeation has been verified. By molecular simulations, the diffusion coefficients of water with different DCM contents were determined. The results showed that the diffusion coefficient decreased rapidly from 53.33 × 10–6 to 6.73 × 10–6 cm2/s after decreasing the DCM mass fraction from 94 to 63%. Furthermore, the higher stirring speed and lower volume of the external aqueous phase promoted the DCM volatilization. Two different mass transfer stages were identified for water permeation, and the first stage could be considered the main mass transfer window because of its high diffusion coefficient. The morphology of PLGA microspheres confirmed the existence of a relationship between water permeation and DCM volatilization.
研究领域:
材料科学
·
制药工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2023
·
IF 6.4
Qing Dai,Qin Ling,Like Huang,Xiaohui Liu,Houcheng Zhang,Jing Zhang,Yuejin Zhu,Ziyang Hu
Two-dimensional (2D) perovskites have attracted significant attention in recent years due to their promising light harvesting and emissive properties. However, the realization of 2D perovskite crystallization with sufficient coverage and reliable reproducibility remains difficult. In this study, controlling the solvent volatilization to achieve high-quality crystallization with full coverage and lateral homogeneity of 2D Ruddlesden–Popper phase perovskite was effectively achieved. It is found that variations in the solvent evaporation rate give rise to lateral film coverage gradients with the degree of grain fusion during the process of hot-casting. As a result, the obtained photovoltaic efficiency varies due to the growth inhomogeneity across hot-casting thin films from center to edge. By adjusting the temperature of the casting perovskite precursor, film inhomogeneity and device performance variation can be alleviated. Regulating radial morphology across hot-casting thin films will enable coating techniques amenable to the solution process for robust reproducibility.
研究领域:
材料科学
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光伏技术
✓ 已验证
产品关联
DOI
高影响因子
Science Bulletin
·
2021
·
IF 11.78
Weijun Li,Huayang Li,Jinmei Song,Chunjie Guo,Huimao Zhang,Haotong Wei,Bai Yang
Halide perovskite single crystals (HPSCs) provide a unique platform to study the optoelectronic properties of such emerging semiconductor materials, while the temperature induced crystal growth method often has an increased solute integration speed and/or unavoidable solute consumption, resulting in a soaring or slumping crystal growth rate of HPSCs. Here, we developed a universal and facile solvent-volatilization-limited-growth (SVG) strategy to finely control the crystal growth rate by the fine-control-valve for high quality crystal grown through solution processes. The grown HPSCs by SVG method exhibited a record low trap density of 2.8 × 10 8 cm −3 and a high charge carrier mobility-lifetime product ( μτ product) of 0.021 cm 2 /V, indicating the excellent crystal quality. The crystal surface defects were further passivated by oxygen suppliers as Lewis base, which led to a reduction of surface leakage current by two times when using for low dose rate X-ray detection. Such HPSC X-ray detector displayed a high sensitivity of 1274 µC/(Gy air cm 2 ) with a lowest detectable dose rate of 0.56 μGy air /s under 120 keV hard X-ray. Further applications including alloy composition analysis and metal flaw detection by HPSC detectors were also demonstrated, which not only shows the bright future for product quality inspection and non-destructive materials analysis, but also paves the way for growing high quality single crystals and fabricating polycrystalline films.
研究领域:
材料科学
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半导体物理
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辐射探测技术
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产品关联
DOI
PubMed
高影响因子
Soft Matter
·
2011
·Vol. 7
·期 18
·8376-8383
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IF 4.457
Bin Ding,Jinyou Lin,Xianfeng Wang,Jianyong Yu,Jianmao Yang,Yu Cai
A number of fascinating properties of micro/nano-fibers can be obtained as their fine-structures are tuned. Here, we report a one-step procedure to construct nanoporous polystyrene (PS) fibers loaded with controllably distributed silica nanoparticlesvia tuning the solvent compositions in electrospinning. With decreasing solvent vapor pressure in electrospinning, the silica nanoparticles were clearly observed to be transferred from the interior of the PS fiber to its surface due to the phase separation of fluid jet in varying degrees. The silica nanoparticles embedded in the fibers exhibited porous cores contributing to an increase in Brunauer–Emmett–Teller surface area of the as-spun fibers. The presence of silica nanoparticles on the fiber surfaces enhanced the surface roughness with numerous papillae. Water droplets on a typical fiber surface readily sat on the apex of papillae because the air filled in these hierarchically roughened fibrous mats as a cushion, and therefore, displayed superhydrophobicity with a water contact angle of 156.7°. We believe that the exploitation of such a simple method for fine-controlling structures of micro/nano-fibers will endow these materials with new properties for some special applications such as in novel easy-cleaning coatings, microfluidic devices, and even smart membranes.
研究领域:
高分子材料科学
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纳米技术
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表面科学
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生物医学工程
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功能材料
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Tingyu Wang,Dan Wang,Bailiang Li,Ling Huang,Liling Cao,Xuehua Dong,Guohong Zou
Two antimony-based oxalofluoride crystals, (NH4)2Sb(C2O4)1.5F2·H2O (1) and (NH4)Sb(C2O4)F2·H2O (2), were synthesized via a solvent evaporation method. Both compounds feature a [SbO4F2]7– pentagonal pyramid and planar π-conjugated [C2O4]2– groups, interconnected through hydrogen-bond networks. They exhibit large birefringence values of 0.24 and 0.22 at 546 nm, respectively, along with wide optical band gaps of 3.93 and 3.75 eV. Combined experimental and theoretical analyses reveal that the pronounced optical anisotropy originates from the synergistic effect of stereochemically active lone-pair electrons, π-conjugated anions, and dense hydrogen bonding. This work provides a viable strategy for designing UV birefringent materials through cooperative structural modulation at the molecular level.
研究领域:
材料科学
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无机化学
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光学
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晶体工程
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理论化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Coatings Technology and Research
·
2025
·
IF 2.8
Zhang Linbo,Hong Mu-Nai Jin,Yang Ruoyu,Jiang Xianyu,Zhou Yusheng,Zhang Tongqing,Yuan Le
This study develops and explores a self-stratifying coating system that incorporates both epoxy and acrylic resins. It examines the impact of film thickness and substrate type on self-stratification behavior, confirms predictions from the surface energy model, and identifies the surface tension gradient as the primary driving mechanism for stratification. Additionally, this research investigates the influence of FeSiCr powder on the stratification behavior of the coating. Results demonstrate that the self-stratifying coating, composed of a blend of epoxy and acrylic resins with FeSiCr powder, exhibits superior corrosion resistance compared to coatings formulated solely from a mixture of epoxy resin and FeSiCr powder. SEM-EDS analysis reveals that the enhanced corrosion resistance can be attributed to the accumulation of epoxy resin and FeSiCr at the bottom of the coating, while the acrylic resin forms an effective protective layer on the surface. Furthermore, the study examines the effects of FeSiCr powder content, solvent addition, and volatilization rate on the stratified structure and appearance of the coating. The findings indicate that at relatively low FeSiCr powder content, the layered structure of the coating remains largely intact, with the powder predominantly residing within the epoxy resin layer. However, increasing the powder content compromises the self-stratification structure, leading to a rougher coating surface. It is also observed that augmenting the quantity of the xylene/butyl acetate mixture reduces pit formation on the surface, while the use of MIBK solvent results in incomplete stratification and exacerbates surface roughness.
研究领域:
材料科学
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涂层技术
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腐蚀工程
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高分子科学
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表面化学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2023
·Vol. 19
·期 52
·2305357
·
IF 13.3
Yingjun Chai,Chaoyan Jiang,Xudong Hu,Jiguang Han,Yao Wang,Wanqiu Yang,Chongkang Li,Haibo Zeng,Xiaoming Li
Solution-processed organic–inorganic hybrid perovskite polycrystalline thick films have shown great potential in X-ray detection. However, the preparation of compact perovskite thick films with large area is still challenging due to the limitation of feasible ink formulation and pinholes caused by solvent volatilization. Post-treatment and hot-pressing are usually involved to improve the film quality, which is however unsuitable for subsequent integration. In this work, a homogeneous bridging strategy is developed to prepare compact perovskite films directly. A stable perovskite slurry with suitable viscosity consisting of undissolved grains and supersaturated solution is formed by adding a weak coordination solvent to the pre-synthesized microcrystalline powders. Small perovskite grains in situ grow from the saturated solution during the annealing, filling the pinholes and connecting the surrounding original grains. As a result, large-area perovskite thick film with tight grain arrangement and ultralow current drift is blade-coated to achieve X-ray imaging. The optimal device displays an impressive mobility-lifetime product of 2.2 × 10 −3 cm 2 V −1 and a champion ratio of sensitivity to the dark current density of 2.23 × 10 11 µC Gy air −1 A −1 . This work provides a simple and effective route to prepare high-quality perovskite thick films, which is instructive for the development of perovskite-based X-ray flat-panel detectors.
研究领域:
材料科学
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纳米技术
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半导体器件
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X射线检测
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薄膜加工
✓ 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）