000079736 001__ 79736
000079736 005__ 20200117221633.0
000079736 0247_ $$2doi$$a10.1063/1.5042671
000079736 0248_ $$2sideral$$a108072
000079736 037__ $$aART-2018-108072
000079736 041__ $$aeng
000079736 100__ $$aVasin, A.V.
000079736 245__ $$aMultiband light emission and nanoscale chemical analyses of carbonized fumed silica
000079736 260__ $$c2018
000079736 5060_ $$aAccess copy available to the general public$$fUnrestricted
000079736 5203_ $$aFumed silica with a specific area of 295 m(2)/g was carbonized by successive phenyltrimethoxysilane treatments followed by annealing in inert atmosphere up to 650 degrees 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 sp(2) carbon in these nanoclusters has been estimated to be close to 80%. Published by AIP Publishing.
000079736 536__ $$9info:eu-repo/grantAgreement/ES/DGA/E26$$9info:eu-repo/grantAgreement/ES/MINECO/MAT2016-79776-P
000079736 540__ $$9info:eu-repo/semantics/openAccess$$aAll rights reserved$$uhttp://www.europeana.eu/rights/rr-f/
000079736 590__ $$a2.328$$b2018
000079736 591__ $$aPHYSICS, APPLIED$$b59 / 148 = 0.399$$c2018$$dQ2$$eT2
000079736 592__ $$a0.746$$b2018
000079736 593__ $$aPhysics and Astronomy (miscellaneous)$$c2018$$dQ2
000079736 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion
000079736 700__ $$aKysil, D.V.
000079736 700__ $$0(orcid)0000-0001-6152-6784$$aLajaunie, L.
000079736 700__ $$aRudko, G.Y.
000079736 700__ $$aLysenko, V.S.
000079736 700__ $$aSevostianov, S.V.
000079736 700__ $$aTertykh, V.A.
000079736 700__ $$aPiryatinski, Y.P.
000079736 700__ $$aCannas, M.
000079736 700__ $$aVaccaro, L.
000079736 700__ $$0(orcid)0000-0002-2071-9093$$aArenal, R.$$uUniversidad de Zaragoza
000079736 700__ $$aNazarov, A.N.
000079736 7102_ $$12003$$2395$$aUniversidad de Zaragoza$$bDpto. Física Materia Condensa.$$cÁrea Física Materia Condensada
000079736 773__ $$g124, 10 (2018), 105108 [12 pp]$$pJ. appl. physi.$$tJournal of Applied Physics$$x0021-8979
000079736 8564_ $$s688382$$uhttps://zaguan.unizar.es/record/79736/files/texto_completo.pdf$$yVersión publicada
000079736 8564_ $$s128949$$uhttps://zaguan.unizar.es/record/79736/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada
000079736 909CO $$ooai:zaguan.unizar.es:79736$$particulos$$pdriver
000079736 951__ $$a2020-01-17-22:00:53
000079736 980__ $$aARTICLE