Multiband light emission and nanoscale chemical analyses of carbonized fumed silica

Lavinia Vaccaro, Marco Cannas, Arenal, Lajaunie, Volodymyr Lysenko, Nazarov, Kysil, Sevostianov, Yu. P. Piryatinski, G. Yu. Rudko, Tertykh, Vasin

Risultato della ricerca: Article

2 Citazioni (Scopus)

Abstract

Fumed silica with a specific area of 295 m2/g was carbonized by successive phenyltrimethoxysilane treatments followed by annealing in inert atmosphere up to 650 °C. Emission, excitation, kinetics, and photo-induced bleaching effects were investigated by steady state and time-resolved photoluminescence spectroscopies. The local chemistry was also studied by infrared transmission spectroscopy. Strong ultraviolet and visible photoluminescence was observed in the samples after the chemical treatments/modifications and thermal annealing. It has been shown that ultraviolet photoluminescence in chemically modified fumed silica is associated with phenyl groups, while near ultraviolet and visible emission in annealed samples originated from inorganic pyrolytic carbon precipitates dispersed in the silica host matrix. Two types of emission bands were identified as a function of the annealing temperature: one is in the near UV and the other is in the visible range. Based on the emission/excitation analysis of these two bands, as well as on correlations with the synthesis conditions, a structural-energy concept of light-emitting centers has been proposed. According to this model, the light-emitting centers are associated with carbon clusters that can be bonded or adsorbed on the silica surface. This has been validated by a detailed (S)TEM-electron energy-loss spectroscopy study, confirming the inhomogeneous distribution of nanoscale carbon precipitates at the surface of the silica nanoparticles. These carbon precipitates are mostly amorphous although they possess some degree of graphitization and local order. Finally, the fraction of sp2carbon in these nanoclusters has been estimated to be close to 80%.
Lingua originaleEnglish
pagine (da-a)105108-
Numero di pagine12
RivistaJournal of Applied Physics
Volume124
Stato di pubblicazionePublished - 2018

Fingerprint

light emission
silicon dioxide
precipitates
carbon
photoluminescence
annealing
spectroscopy
inert atmosphere
graphitization
ultraviolet emission
bleaching
nanoclusters
excitation
energy dissipation
electron energy
chemistry
nanoparticles
transmission electron microscopy
kinetics
synthesis

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

Cita questo

Multiband light emission and nanoscale chemical analyses of carbonized fumed silica. / Vaccaro, Lavinia; Cannas, Marco; Arenal; Lajaunie; Lysenko, Volodymyr; Nazarov; Kysil; Sevostianov; Piryatinski, Yu. P.; Rudko, G. Yu.; Tertykh; Vasin.

In: Journal of Applied Physics, Vol. 124, 2018, pag. 105108-.

Risultato della ricerca: Article

Vaccaro, L, Cannas, M, Arenal, Lajaunie, Lysenko, V, Nazarov, Kysil, Sevostianov, Piryatinski, YP, Rudko, GY, Tertykh & Vasin 2018, 'Multiband light emission and nanoscale chemical analyses of carbonized fumed silica', Journal of Applied Physics, vol. 124, pagg. 105108-.
Vaccaro, Lavinia ; Cannas, Marco ; Arenal ; Lajaunie ; Lysenko, Volodymyr ; Nazarov ; Kysil ; Sevostianov ; Piryatinski, Yu. P. ; Rudko, G. Yu. ; Tertykh ; Vasin. / Multiband light emission and nanoscale chemical analyses of carbonized fumed silica. In: Journal of Applied Physics. 2018 ; Vol. 124. pagg. 105108-.
@article{7a4e8d050f0949eda78692a450266a84,
title = "Multiband light emission and nanoscale chemical analyses of carbonized fumed silica",
abstract = "Fumed silica with a specific area of 295 m2/g was carbonized by successive phenyltrimethoxysilane treatments followed by annealing in inert atmosphere up to 650 °C. Emission, excitation, kinetics, and photo-induced bleaching effects were investigated by steady state and time-resolved photoluminescence spectroscopies. The local chemistry was also studied by infrared transmission spectroscopy. Strong ultraviolet and visible photoluminescence was observed in the samples after the chemical treatments/modifications and thermal annealing. It has been shown that ultraviolet photoluminescence in chemically modified fumed silica is associated with phenyl groups, while near ultraviolet and visible emission in annealed samples originated from inorganic pyrolytic carbon precipitates dispersed in the silica host matrix. Two types of emission bands were identified as a function of the annealing temperature: one is in the near UV and the other is in the visible range. Based on the emission/excitation analysis of these two bands, as well as on correlations with the synthesis conditions, a structural-energy concept of light-emitting centers has been proposed. According to this model, the light-emitting centers are associated with carbon clusters that can be bonded or adsorbed on the silica surface. This has been validated by a detailed (S)TEM-electron energy-loss spectroscopy study, confirming the inhomogeneous distribution of nanoscale carbon precipitates at the surface of the silica nanoparticles. These carbon precipitates are mostly amorphous although they possess some degree of graphitization and local order. Finally, the fraction of sp2carbon in these nanoclusters has been estimated to be close to 80{\%}.",
author = "Lavinia Vaccaro and Marco Cannas and Arenal and Lajaunie and Volodymyr Lysenko and Nazarov and Kysil and Sevostianov and Piryatinski, {Yu. P.} and Rudko, {G. Yu.} and Tertykh and Vasin",
year = "2018",
language = "English",
volume = "124",
pages = "105108--",
journal = "Journal of Applied Physics",
issn = "0021-8979",
publisher = "American Institute of Physics Publising LLC",

}

TY - JOUR

T1 - Multiband light emission and nanoscale chemical analyses of carbonized fumed silica

AU - Vaccaro, Lavinia

AU - Cannas, Marco

AU - Arenal, null

AU - Lajaunie, null

AU - Lysenko, Volodymyr

AU - Nazarov, null

AU - Kysil, null

AU - Sevostianov, null

AU - Piryatinski, Yu. P.

AU - Rudko, G. Yu.

AU - Tertykh, null

AU - Vasin, null

PY - 2018

Y1 - 2018

N2 - Fumed silica with a specific area of 295 m2/g was carbonized by successive phenyltrimethoxysilane treatments followed by annealing in inert atmosphere up to 650 °C. Emission, excitation, kinetics, and photo-induced bleaching effects were investigated by steady state and time-resolved photoluminescence spectroscopies. The local chemistry was also studied by infrared transmission spectroscopy. Strong ultraviolet and visible photoluminescence was observed in the samples after the chemical treatments/modifications and thermal annealing. It has been shown that ultraviolet photoluminescence in chemically modified fumed silica is associated with phenyl groups, while near ultraviolet and visible emission in annealed samples originated from inorganic pyrolytic carbon precipitates dispersed in the silica host matrix. Two types of emission bands were identified as a function of the annealing temperature: one is in the near UV and the other is in the visible range. Based on the emission/excitation analysis of these two bands, as well as on correlations with the synthesis conditions, a structural-energy concept of light-emitting centers has been proposed. According to this model, the light-emitting centers are associated with carbon clusters that can be bonded or adsorbed on the silica surface. This has been validated by a detailed (S)TEM-electron energy-loss spectroscopy study, confirming the inhomogeneous distribution of nanoscale carbon precipitates at the surface of the silica nanoparticles. These carbon precipitates are mostly amorphous although they possess some degree of graphitization and local order. Finally, the fraction of sp2carbon in these nanoclusters has been estimated to be close to 80%.

AB - Fumed silica with a specific area of 295 m2/g was carbonized by successive phenyltrimethoxysilane treatments followed by annealing in inert atmosphere up to 650 °C. Emission, excitation, kinetics, and photo-induced bleaching effects were investigated by steady state and time-resolved photoluminescence spectroscopies. The local chemistry was also studied by infrared transmission spectroscopy. Strong ultraviolet and visible photoluminescence was observed in the samples after the chemical treatments/modifications and thermal annealing. It has been shown that ultraviolet photoluminescence in chemically modified fumed silica is associated with phenyl groups, while near ultraviolet and visible emission in annealed samples originated from inorganic pyrolytic carbon precipitates dispersed in the silica host matrix. Two types of emission bands were identified as a function of the annealing temperature: one is in the near UV and the other is in the visible range. Based on the emission/excitation analysis of these two bands, as well as on correlations with the synthesis conditions, a structural-energy concept of light-emitting centers has been proposed. According to this model, the light-emitting centers are associated with carbon clusters that can be bonded or adsorbed on the silica surface. This has been validated by a detailed (S)TEM-electron energy-loss spectroscopy study, confirming the inhomogeneous distribution of nanoscale carbon precipitates at the surface of the silica nanoparticles. These carbon precipitates are mostly amorphous although they possess some degree of graphitization and local order. Finally, the fraction of sp2carbon in these nanoclusters has been estimated to be close to 80%.

UR - http://hdl.handle.net/10447/310959

UR - http://scitation.aip.org/content/aip/journal/jap

M3 - Article

VL - 124

SP - 105108-

JO - Journal of Applied Physics

JF - Journal of Applied Physics

SN - 0021-8979

ER -