排序方式: 共有57条查询结果,搜索用时 406 毫秒
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Dr. Robert Ludmerczki Prof. Luca Malfatti Dr. Luigi Stagi Dr. Manuela Meloni Prof. Carlo Maria Carbonaro Prof. Maria Francesca Casula Dr. Dóra Bogdán Dr. Stefania Mura Prof. István M. Mándity Prof. Plinio Innocenzi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(7):2543-2550
Carbonized polymer dots (CPDs), a peculiar type of carbon dots, show extremely high quantum yields, making them very attractive nanostructures for application in optics and biophotonics. The origin of the strong photoluminescence of CPDs resides in a complicated interplay of several radiative mechanisms. To understand the correlation between CPD processing and properties, the early stage formation of carbonized polymer dots has been studied. In the synthesis, citric acid monohydrate and 2-amino-2-(hydroxymethyl)propane-1,3-diol have been thermally degraded at 180 °C. The use of an oil bath instead of a more traditional hydrothermal reactor has allowed the CPD properties to be monitored at different reactions times. Transmission electron microscopy, time-resolved photoluminescence, nuclear magnetic resonance, infrared, and Raman spectroscopy have revealed the formation of polymeric species with amide and ester bonds. Quantum chemistry calculations have been employed to investigate the origin of CPD electronic transitions. At short reaction times, amorphous C-dots with 80 % quantum yield, have been obtained. 相似文献
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Tuning the phase transition of ZnO thin films through lithography: an integrated bottom‐up and top‐down processing 下载免费PDF全文
Luca Malfatti Alessandra Pinna Stefano Enzo Paolo Falcaro Benedetta Marmiroli Plinio Innocenzi 《Journal of synchrotron radiation》2015,22(1):165-171
An innovative approach towards the physico‐chemical tailoring of zinc oxide thin films is reported. The films have been deposited by liquid phase using the sol–gel method and then exposed to hard X‐rays, provided by a synchrotron storage ring, for lithography. The use of surfactant and chelating agents in the sol allows easy‐to‐pattern films made by an organic–inorganic matrix to be deposited. The exposure to hard X‐rays strongly affects the nucleation and growth of crystalline ZnO, triggering the formation of two intermediate phases before obtaining a wurtzite‐like structure. At the same time, X‐ray lithography allows for a fast patterning of the coatings enabling microfabrication for sensing and arrays technology. 相似文献
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Hans Malfatti 《Fresenius' Journal of Analytical Chemistry》1893,32(1):754-761
Ohne Zusammenfassung 相似文献
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Tongjit Kidchob Luca Malfatti Daniela Marongiu Stefano Enzo Plinio Innocenzi 《Journal of Sol-Gel Science and Technology》2009,52(3):356-361
The process of formation of cerium titanate films as a function of annealing temperature and composition has been studied
by combining X-ray diffraction analysis and far infrared spectroscopy. The films have been prepared by a sol–gel synthesis
using metal chlorides as precursors; the synthesis allows obtaining cerium titanate films upon annealing in air. A brannerite
type, CeTi2O6, phase has been identified by X-ray diffraction and Rietveld analysis on thin films. CeTi2O6 is formed upon annealing at 700 °C and in a limited range of ceria-titania mixed compositions. The far infrared spectra are
useful to observe the formation of crystalline phases at the beginning of the crystallization process at lower firing temperatures,
when the XRD analysis is not enough sensitive. 相似文献
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Sol‐to‐Gel Transition in Fast Evaporating Systems Observed by in Situ Time‐Resolved Infrared Spectroscopy 下载免费PDF全文
Prof. Dr. Plinio Innocenzi Dr. Luca Malfatti Dr. Davide Carboni Prof. Dr. Masahide Takahashi 《Chemphyschem》2015,16(9):1933-1939
The in situ observation of a sol‐to‐gel transition in fast evaporating systems is a challenging task and the lack of a suitable experimental design, which includes the chemistry and the analytical method, has limited the observations. We synthesise an acidic sol, employing only tetraethylorthosilicate, SiCl4 as catalyst and deuterated water; the absence of water added to the sol allows us to follow the absorption from the external environment and the evaporation of deuterated water. The time‐resolved data, obtained by attenuated total reflection infrared spectroscopy on an evaporating droplet, enables us to identify four different stages during evaporation. They are linked to specific hydrolysis and condensation rates that affect the uptake of water from external environment. The second stage is characterized by a decrease in hydroxyl content, a fast rise of condensation rate and an almost stationary absorption of water. This stage has been associated with the sol‐to‐gel transition. 相似文献
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Hans Malfatti 《Fresenius' Journal of Analytical Chemistry》1911,50(11):692-693
Ohne Zusammenfassung 相似文献
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Plinio Innocenzi Tongjit Kidchob Luca Malfatti Stefano Costacurta Masahide Takahashi Massimo Piccinini Augusto Marcelli 《Journal of Sol-Gel Science and Technology》2008,48(1-2):253-259
Sol–gel processing of thin films involves time dependent phenomena which are basically driven by solvent evaporation. An example is evaporation induced self-assembly that is used to prepare mesoporous ordered films through self-organization of templating micelles. The possibility to follow in situ as a function of time the evolution of the system can give a better knowledge of the process and the physics and chemistry beneath. Time-resolved infrared techniques have been applied to different sol–gel systems to study time-dependent phenomena, in particular rapid scan time resolved infrared spectroscopy has been used to monitor in situ the process and as a tool to design the sol–gel synthesis. 相似文献
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V. Henriques L. de Jager S. P. L. Sörensen H. Jessen-Hansen H. Malfatti O. v. Spindler H. Björn-Andersen Marius Laritzen T. Yoshida W. Frey und A. Gigon 《Fresenius' Journal of Analytical Chemistry》1911,50(8):528-534
Ohne ZusammenfassungVergl. auch diese Zeitschrift47, 547;49, 66. 相似文献