p-n Heterojunction formation in polyaniline-SnO2 organic-inorganic hybrid composite materials leading to enhancement in sensor functionality toward benzene and toluene vapors at room temperature

Organic-inorganic hybrid composite (OIHC) materials were synthesized through physical grinding of conducting p-polyaniline and n-SnO2 with different weight %. Characterization by FT-IR, XRD, SEM and AC impedance studies revealed a mutual interaction and formation of p-n heterojunctions. In N-2 atmosphere OIHC materials had enhancement in sensor functionality toward benzene and toluene vapors at room temperature. Good correlation existed between number of p-n heterojunctions and sensor efficiencies. An optimized material with 40 wt% SnO2 showed 10% sensor efficiency for benzene and slightly higher value for toluene. Considering weak/nil interaction of analyte, the present work produced fairly efficient hybrid sensor materials from almost insensitive organic and inorganic components. (c) 2014 Elsevier B.V. All rights reserved.