Abstract
Gelation times of tetraethyl orthosilicate-derived sols containing selected di- to tetravalent cations as dopants were noted at different temperatures (15°–50°C). An analysis of these data, in conjunction with relevant published information, led to the tentative conclusions that (i) unhydrolyzed cations in bare form linked negatively charged silicate polymers in sols, thereby accelerating gelation and (ii) hydrolyzed cations retarded the process by offering molecular size-related hindrance and competition for the available water for hydrolysis.
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References
Aizawa M, Nosaka Y and Fujii N 1994J. Non-Cryst. Solids 168 49
Baes C F and Messmer R E 1976The hydrolysis of cations (New York: Wiley Interscience)
Bansal N P 1990J. Am. Ceram. Soc. 73 2647
Boilot J P, Pouxviel J C, Dauger A and Wright A 1988Mater. Res. Soc. Symp. Proc. 121 121
Bottero J Y, Tchouber D, Cases J M and Flessinger F 1982J. Phys. Chem. 86 3667
Clearfield A and Vaughan P A 1956Acta Cryst. 9 555
Dienert F and Wandenbulcke F 1924Compt. Rend. 178 564
Fukui T, Sakurai C and Okuyama M 1992J. Non-Cryst. Solids 139 205
Ganguli D 1988J. Non-Cryst. Solids 101 117
Greenwood N N and Earnshaw A 1984Chemistry of the elements (Oxford: Pergamon)
Hurd C B, Rhoades J W, Gormley W G and Santora A C 1958J. Phys. Chem. 62 882
Irwin A D, Holmgren J S, Zerda T W and Jonas J 1987J. Non-Cryst. Solids 89 191
Klein L C 1987 inDesign of new materials (ed) D L Cocke and A Clearfield (New York: Plenum Press) pp 39–65
Kloprogge J T, Sayken D, Jansen J B H and Geus J W 1993J. Non-Cryst. Solids 152 207
Lopez T, Romero A and Gomez R 1991J. Non-Cryst. Solids 127 105
McCormick A V, Bell A T and Radke C J 1987Zeolites 7 193
McCormick A V, Bell A T and Radke C J 1989J. Phys. Chem. 93 1733
Moeller T 1973 inComprehensive inorganic chemistry (ed) J C Bailer, H J Emeleus, R Nyholm and A F Trotman-Dickenson (Oxford: Pergamon) vol4 pp 1–101
Moreshead W V, Nogues J-L R and Krabill R H 1990J. Non-Cryst. Solids 121 267
Murakata T, Sato S, Ohgawara T, Watanabe W and Suzuki W 1992J. Mater. Sci. 27 1567
Patra A 1992Preparation and characterization of pure and doped silica by sol-gel processing, Ph.D. thesis, Jadavpur University, Jadavpur
Patra A and Ganguli D 1992aJ. Non-Cryst. Solids 139 165
Patra A and Ganguli D 1992bTrans. Indian Ceram. Soc. 51 105
Ramsay J D F 1994 inControlled particle, droplet and bubble formation (ed) D J Wedlock (Oxford: Butterworth-Heinemann) pp 1–38
Sanchez J and McCormick A 1991Chem. Mater. 3 320
Thomas I M, Payne S A and Wilke G D 1992J. Non-Cryst. Solids 151 183
Wijnen P W J G, Beelen T P M, Rummens K P J and van Santen R A 1993J. Non-Cryst. Solids 152 127
Woignier T, Phalippou J and Zarzycki J 1984J. Non-Cryst. Solids 63 117
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Patra, A., Ganguli, D. Role of dopant cations in the gelation behaviour of silica sols. Bull. Mater. Sci. 17, 999–1004 (1994). https://doi.org/10.1007/BF02757576
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DOI: https://doi.org/10.1007/BF02757576