Capacitive type humidity sensor based on PANI decorated Cu–ZnS porous microspheres

Abstract

Porous microstructure materials are considered good candidates for the development of highly sensitive and fast humidity sensors. In this regard, we prepared polyaniline (PANI) decorated Cu–ZnS porous microsphere structures (PMSs) for the fabrication of humidity sensors. PANI coated Cu–ZnS PMSs were synthesized by a hydrothermal method and in situ polymerization process. The synthesized PMSs were characterized by different techniques to study the structural, morphological and surface absorption properties. Several compositions for the PANI/Cu–ZnS PMS were investigated, which were then compared with pure PANI. The experimental observations demonstrate that a PANI/1%Cu–ZnS PMS has better sensitivity, fast response and good stability compared to pure PANI and other PANI/CuZnS compositions. Finally, a PANI/1% Cu–ZnS PMS was found to be optimized for humidity sensors due to its well distributed roughness, porosity and hydrophilicity. The average response and recovery times for PANI/1% Cu–ZnS were found to be 42 s and 24 s, respectively, which outperform recent results.