Synthesis and humidity sensitivity of conducting polyaniline in SBA-15

Conducting polyaniline (PANI) was synthesized in mesoporous silica SBA-15. The investigations of XRD, N-2 adsorption-desorption, and IR spectra confirm the existence of polyaniline in the channels of SBA-15 hosts. The impedance of PANI/SBA-15 composites was studied at different relative humidity (RH) levels, ranging from 11 to 95% RH. The loadings of PANI as well as the concentration of HCl solution have substantial influence on the impedance values. The variation in impedance value of all PANI/SBA-15 composites is more obvious than that of bulk PANI samples at the same RH. All these results imply that PANI/SBA-15 composites may have better humidity-sensitive properties than those of bulk PANI samples. (C) 2004 Wiley Periodicals, Inc.