Variation of surface properties and textural features of spinel ZnAl2O4 and perovskite LaMnO3 nanoparticles prepared via CTAB-butanol-octane-nitrate salt microemulsions in the reverse and bicontinuous states
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Ημερομηνία
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
Elsevier
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
J Colloid Interface Sci
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
Two binary oxides, a spinel, ZnAl2O4, and a typical perovskite, LaMnO3, have been prepared via CTAB-1-butanol-n-octane-nitrate salt microemulsion in the reverse and bicontinuous states. The exact point of the reverse and bicontinuous states of the microemulsion used in the synthesis was determined by conductivity experiments. The materials obtained after heating at 800 degreesC were characterized by XRD analysis for their crystal structure, N-2 porosimetry for their surface area and porosity, and SEM and TEM photography for their texture. The ZnAl2O4 spinel obtained via the reverse microemulsion appears in SEM in a more fragmented form and with a higher specific surface area (143.7 m(2) g(-1)), compared to the corresponding solid prepared via the bicontinuous microemulsion, which appears more robust with lower surface area (126.7 m(2) g(-1)). Nevertheless both materials reveal in TEM a sponge-like structure. The perovskite materials LaMnO3 prepared via the reverse microemulsion showed in SEM a peculiar doughnut-like texture, each doughnut-like secondary particle having a diameter of 2 put. The corresponding sample developed via the bicontinuous microemulsion showed in SEM uniform secondary particles of size similar to0.2 mum. Both perovskite samples LaMnO3 appear well crystallized with relative low surface areas, 23.7 m(2) g(-1) for the reverse sample and 10.9 m(2) g(-1) for the bicontinuous one. The TEM photographs reveal that both of them, of reversed and bicontinuous origin, are made up of primary nanoparticles in the size range 40-100 nm. In SEM those materials showed a different secondary structure. (C) 2003 Elsevier Science (USA). All rights reserved.
Περιγραφή
Λέξεις-κλειδιά
microemulsion, reverse microemulsion, bicontinuous microemulsion, spinel znal2o4, perovskite lamno3, in-oil microemulsions, high-coercivity, micelles, powders
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
<Go to ISI>://000182019800005
http://ac.els-cdn.com/S0021979702000681/1-s2.0-S0021979702000681-main.pdf?_tid=5ba05dcb5b7361f2bfd1958b9e039af5&acdnat=1333113664_4aa1663a34713c0abfeb3f98665eb628
http://ac.els-cdn.com/S0021979702000681/1-s2.0-S0021979702000681-main.pdf?_tid=5ba05dcb5b7361f2bfd1958b9e039af5&acdnat=1333113664_4aa1663a34713c0abfeb3f98665eb628
Γλώσσα
en
Εκδίδον τμήμα/τομέας
Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Χημείας