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Preparation of highly dispersed nano-La2O3 particles using modified carbon black as an agglomeration inhibitor / Guirong Wang in Industrial & engineering chemistry research, Vol. 51 N° 45 (Novembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 45 (Novembre 2012) . - pp. 14692-14699 Titre : Preparation of highly dispersed nano-La2O3 particles using modified carbon black as an agglomeration inhibitor Type de document : texte imprimé Auteurs : Guirong Wang, Auteur ; Yongshan Zhou, Auteur ; David G. Evans, Auteur Année de publication : 2013 Article en page(s) : pp. 14692-14699 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Agglomeration  Carbon  black  Preparation Résumé : Nanoparticles readily agglomerate, especially during nucleation, growth, and calcination processes. In this work, modified carbon black (MCB) has been used to prevent particle agglomeration during the nucleation step in the preparation of a highly dispersed nano-La(OH), precursor by a coprecipitation reaction. The surface carboxyl groups formed on MCB after modification can adsorb and fix positively charged La3+ ions on the surface. Therefore, nano-La(OH)3 nuclei can be uniformly deposited on the MCB surface. After nucleation, La(OH)3 particles with a size of about 20 nm with a positive surface charge still interact strongly with the negatively charged MCB surface, which effectively prevents their agglomeration during the subsequent aging process. Furthermore, due to the release of CO2 over a wide temperature range from 400 to 700 °C during a subsequent calcination process, La2O3 particles obtained by calcination of the La(OH)3 precursor can be effectively isolated at high temperature and prevented from agglomerating. By using MCB as an agglomeration inhibitor in this way, highly dispersed La2O3 nanoparticles with a size of 50 nm having excellent photoluminescence ability can be prepared. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26620382 [article] Preparation of highly dispersed nano-La2O3 particles using modified carbon black as an agglomeration inhibitor [texte imprimé] / Guirong Wang, Auteur ; Yongshan Zhou, Auteur ; David G. Evans, Auteur . - 2013 . - pp. 14692-14699. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 45 (Novembre 2012) . - pp. 14692-14699 Mots-clés : Agglomeration  Carbon  black  Preparation Résumé : Nanoparticles readily agglomerate, especially during nucleation, growth, and calcination processes. In this work, modified carbon black (MCB) has been used to prevent particle agglomeration during the nucleation step in the preparation of a highly dispersed nano-La(OH), precursor by a coprecipitation reaction. The surface carboxyl groups formed on MCB after modification can adsorb and fix positively charged La3+ ions on the surface. Therefore, nano-La(OH)3 nuclei can be uniformly deposited on the MCB surface. After nucleation, La(OH)3 particles with a size of about 20 nm with a positive surface charge still interact strongly with the negatively charged MCB surface, which effectively prevents their agglomeration during the subsequent aging process. Furthermore, due to the release of CO2 over a wide temperature range from 400 to 700 °C during a subsequent calcination process, La2O3 particles obtained by calcination of the La(OH)3 precursor can be effectively isolated at high temperature and prevented from agglomerating. By using MCB as an agglomeration inhibitor in this way, highly dispersed La2O3 nanoparticles with a size of 50 nm having excellent photoluminescence ability can be prepared. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26620382