TY - JOUR

T1 - Proton conductivity of sulfonic acid functionalised mesoporous materials

AU - Marschall, Roland

AU - Bannat, Inga

AU - Caro, Jürgen

AU - Wark, Michael

PY - 2007/2/1

Y1 - 2007/2/1

N2 - A detailed comparison of the proton conductivity of three highly ordered mesoporous silica host materials with large inner surface (Si-MCM-41, Si-SBA-15, Si-SBA-16) functionalised with sulfonic acid groups, which were obtained by anchoring and oxidation of thiol groups, is presented. The samples were characterised by X-ray diffraction, nitrogen adsorption, electron microscopy, FT-infrared spectroscopy and TGA/DTA measurements. The proton conductivity is deduced from impedance spectra taken in the temperature range 60-140 °C. All materials show strong dependence of the proton conductivities on the relative humidity, the degree of functionalisation and the pore geometry parameters. Whereas Si-SBA-16 composite materials are poor proton conductors due to the non-directed cubic 3D pore arrangement, functionalised Si-SBA-15 and Si-MCM-41 with hexagonal 1D pore channels exhibit promising proton conductivities at temperatures above 100 °C. For Si-MCM-41 the higher water storage capability is of additional advantage.

AB - A detailed comparison of the proton conductivity of three highly ordered mesoporous silica host materials with large inner surface (Si-MCM-41, Si-SBA-15, Si-SBA-16) functionalised with sulfonic acid groups, which were obtained by anchoring and oxidation of thiol groups, is presented. The samples were characterised by X-ray diffraction, nitrogen adsorption, electron microscopy, FT-infrared spectroscopy and TGA/DTA measurements. The proton conductivity is deduced from impedance spectra taken in the temperature range 60-140 °C. All materials show strong dependence of the proton conductivities on the relative humidity, the degree of functionalisation and the pore geometry parameters. Whereas Si-SBA-16 composite materials are poor proton conductors due to the non-directed cubic 3D pore arrangement, functionalised Si-SBA-15 and Si-MCM-41 with hexagonal 1D pore channels exhibit promising proton conductivities at temperatures above 100 °C. For Si-MCM-41 the higher water storage capability is of additional advantage.

KW - Functionalised mesoporous silica

KW - Impedance spectroscopy

KW - PEM fuel cell membranes

KW - Proton conductivity

KW - Solid proton conductors

UR - http://www.scopus.com/inward/record.url?scp=33845964246&partnerID=8YFLogxK

U2 - 10.1016/j.micromeso.2006.08.037

DO - 10.1016/j.micromeso.2006.08.037

M3 - Article

AN - SCOPUS:33845964246

VL - 99

SP - 190

EP - 196

JO - Microporous and Mesoporous Materials

JF - Microporous and Mesoporous Materials

SN - 1387-1811

IS - 1-2

ER -