Aqueous Solution Synthesis of CaF2 Hollow Microspheres via the Ostwald Ripening Process at Room Temperature

2009 ◽  
Vol 1 (4) ◽  
pp. 780-788 ◽  
Author(s):  
Wen-Shou Wang ◽  
Liang Zhen ◽  
Cheng-Yan Xu ◽  
Jun-Zhou Chen ◽  
Wen-Zhu Shao
Keyword(s):  
Aqueous Solution ◽  
Room Temperature ◽  
Ostwald Ripening ◽  
Hollow Microspheres ◽  
Solution Synthesis ◽  
Ripening Process

Environmentally Friendly Aqueous Solution Synthesis of Hierarchical CaWO4 Microspheres at Room Temperature

2008 ◽  
Vol 8 (3) ◽  
pp. 1288-1294 ◽  
Author(s):  
Wenshou Wang ◽  
Liang Zhen ◽  
Chengyan Xu ◽  
Baoyou Zhang ◽  
Wenzhu Shao
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Large Scale ◽  
Room Temperature ◽  
Blue Emission ◽  
Environmentally Friendly ◽  
Average Diameter ◽  
Solution Synthesis ◽  
Chemical Route ◽  
Hierarchical Microspheres

An environmentally friendly route for the synthesis of hierarchical CaWO4 microspheres with novel morphology at room temperature has been successfully developed. CaCl2 and Na2WO4 were used as reaction regents, and distilled water was used as an environmentally friendly solvent. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and photoluminescence spectroscopy. This green wet-chemical route provides a simple, one-step, low-cost approach for the large-scale synthesis of hierarchical CaWO4 microspheres with relatively uniform diameters of 3–6 μm. The hierarchical microspheres are built up with numerous nanorods with an average diameter of 50 nm, which are radially oriented to the microsphere center. SEM observations of different intermediates indicate the possible growth process, in which the hierarchical structure growth is from nuclei through kayak-like, rod-like, peanut-like, dumbbell-like, and peach-like structures to final microspheres, via "self-assembled preferential end growth" of kayak-like particles in aqueous solution. The hierarchical CaWO4 micro-spheres exhibit a strong, broad blue emission peak of 412 nm.

Room temperature aqueous solution synthesis of pinacol (C6) by photocatalytic CC coupling of isopropanol

2013 ◽  
Vol 272 ◽  
pp. 1-5 ◽  
Author(s):  
Haiqiang Lu ◽  
Binbin Zhao ◽  
Di Zhang ◽  
Yalan Lv ◽  
Baoping Shi ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Room Temperature ◽  
Solution Synthesis

Fluorescence Spectrum of CdTe Quantum Dots Solution in Ostwald Ripening Process at Room Temperature

2012 ◽  
Vol 268-270 ◽  
pp. 551-554 ◽  
Author(s):  
Li Min An ◽  
Xue Ting Han ◽  
Xuan Lin Chen ◽  
Shao Hong Gao ◽  
Xi Ping Cai ◽  
...  
Keyword(s):  
Fluorescence Spectrum ◽  
Room Temperature ◽  
Ostwald Ripening ◽  
Synthesis Method ◽  
Mixed Solution ◽  
Aqueous Synthesis ◽  
Ripening Process ◽  
Cdte Qds ◽  
Organometallic Precursors ◽  
Average Size

We have developed a new, simple, green and very reproducible aqueous synthesis method for the preparation of different sizes CdTe QDs without the use of any pyrophoric organometallic precursors. Transmission electron microscope image demonstrates the shape, monodispersity, average size and size distribution. Two different sizes CdTe QDs are mixed and standing for three months in aqueous solution. Through UV-Vis absorption spectroscopy and fluorescence spectrum detection, we confirm Ostwald ripening process can also occur in CdTe QDs mixed solution for a long time at room temperature.

Formation of FeMoO4 hollow microspheres via a chemical conversion-induced Ostwald ripening process

CrystEngComm ◽  
2012 ◽  
Vol 14 (20) ◽  
pp. 7025 ◽  
Author(s):  
Jian-Xun Cui ◽  
Wen-Shou Wang ◽  
Liang Zhen ◽  
Wen-Zhu Shao ◽  
Zhong-Lin Chen
Keyword(s):  
Ostwald Ripening ◽  
Chemical Conversion ◽  
Hollow Microspheres ◽  
Ripening Process

scholarly journals Practical Synthesis of 2-Iodosobenzoic Acid (IBA) without Contamination by Hazardous 2-Iodoxybenzoic Acid (IBX) under Mild Conditions

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1897
Author(s):  
Hideyasu China ◽  
Nami Kageyama ◽  
Hotaka Yatabe ◽  
Naoko Takenaga ◽  
Toshifumi Dohi
Keyword(s):  
Aqueous Solution ◽  
Room Temperature ◽  
Practical Method ◽  
Hypervalent Iodine ◽  
Mild Conditions ◽  
Sequential Procedures ◽  
Iodine Compounds ◽  
Practical Synthesis ◽  
Iodosobenzoic Acid ◽  
Lower Temperature

We report a convenient and practical method for the preparation of nonexplosive cyclic hypervalent iodine(III) oxidants as efficient organocatalysts and reagents for various reactions using Oxone® in aqueous solution under mild conditions at room temperature. The thus obtained 2-iodosobenzoic acids (IBAs) could be used as precursors of other cyclic organoiodine(III) derivatives by the solvolytic derivatization of the hydroxy group under mild conditions of 80 °C or lower temperature. These sequential procedures are highly reliable to selectively afford cyclic hypervalent iodine compounds in excellent yields without contamination by hazardous pentavalent iodine(III) compound.

scholarly journals Self-assembly induced luminescence of Eu3+-complexes and application in bioimaging

2021 ◽  
Author(s):  
Ping-Ru Su ◽  
Tao Wang ◽  
Pan-Pan Zhou ◽  
Xiao-Xi Yang ◽  
Xiao-Xia Feng ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Rare Earth ◽  
Luminescence Intensity ◽  
Self Assembly ◽  
Room Temperature ◽  
Molecular Motion ◽  
Proof Of Concept ◽  
Room Temperature Phosphorescence ◽  
New Strategy ◽  
Size Controlled

Abstract Design and engineering of highly efficient emitting materials with assembly-induced luminescence, such as room temperature phosphorescence (RTP) and aggregation-induced emission (AIE), have stimulated extensive efforts. Here, we propose a new strategy to obtain size-controlled Eu3+-complex nanoparticles (Eu-NPs) with self-assembly induced luminescence (SAIL) characteristics without encapsulation or hybridization. Compared with previous RTP or AIE materials, the SAIL phenomena of increased luminescence intensity and lifetime in aqueous solution for the proposed Eu-NPs are due to the combined effect of self-assembly in confining the molecular motion and shielding the water quenching. As a proof of concept, we also show that this system can be further applied in bioimaging, temperature measurement and HClO sensing. The SAIL activity of the rare-earth (RE) system proposed here offers a further step forward on the roadmap for the development of RE light conversion systems and their integration in bioimaging and therapy applications.

scholarly journals Long-Term Stability of Different Kinds of Gas Nanobubbles in Deionized and Salt Water

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1808
Author(s):  
Yali Zhou ◽  
Zhenyao Han ◽  
Chunlin He ◽  
Qin Feng ◽  
Kaituo Wang ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Bubble Size ◽  
Ostwald Ripening ◽  
Salt Water ◽  
Dlvo Theory ◽  
Deionized Water ◽  
Hydrodynamic Cavitation ◽  
Term Stability ◽  
Long Term Stability

Nanobubbles have many potential applications depending on their types. The long-term stability of different gas nanobubbles is necessary to be studied considering their applications. In the present study, five kinds of nanobubbles (N2, O2, Ar + 8%H2, air and CO2) in deionized water and a salt aqueous solution were prepared by the hydrodynamic cavitation method. The mean size and zeta potential of the nanobubbles were measured by a light scattering system, while the pH and Eh of the nanobubble suspensions were measured as a function of time. The nanobubble stability was predicted and discussed by the total potential energies between two bubbles by the extended Derjaguin–Landau–Verwey–Overbeek (DLVO) theory. The nanobubbles, except CO2, in deionized water showed a long-term stability for 60 days, while they were not stable in the 1 mM (milli mol/L) salt aqueous solution. During the 60 days, the bubble size gradually increased and decreased in deionized water. This size change was discussed by the Ostwald ripening effect coupled with the bubble interaction evaluated by the extended DLVO theory. On the other hand, CO2 nanobubbles in deionized water were not stable and disappeared after 5 days, while the CO2 nanobubbles in 1 mM of NaCl and CaCl2 aqueous solution became stable for 2 weeks. The floating and disappearing phenomena of nanobubbles were estimated and discussed by calculating the relationship between the terminal velocity of the floating bubble and bubble size.

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