Preparation of conjugated polymer/reduced graphene oxide nanocomposites for high-performance volatile organic compound sensors

We have reported a facile approach to fabricate poly(3-hexylthiophene)/reduced graphene oxide (P3HT/rGO) composite films via the photoirradiation of the corresponding composite solutions. The films are applied to organic field-effect transistor (OFET) sensors for the high-performance detection of volatile organic compounds (VOCs). The photoirradiation of the composite solutions and the presence of rGO act synergistically to facilitate the molecular ordering of P3HT. Thus, the P3HT/rGO composite films containing 20 wt% rGO exhibit a maximized charge carrier mobility of similar to 0.18 cm(2) V-1 s(-1), which is 6-folds higher than that of pristine P3HT films. The interfacial interactions between rGO and P3HT are enhanced by the favorable pi-pi and electrostatic interactions following photoirradiation. The OFET sensors based on the P3HT/rGO composites consistently show enhanced sensitivity to polar VOCs (methanol, acetone, ethanol, and isopropyl alcohol) compared to those based on the pristine P3HT, photoirradiated bare P3HT, and pristine P3HT/rGO composites. In particular, the photoirradiated P3HT/rGO-based OFET sensors achieve significantly improved responsivity (similar to 110.6%) to methanol vapors (10 ppm) under rapid on/off pulses of 60 s, compared to those based on pristine P3HT (similar to 6.8%), photoirradiated bare P3HT (similar to 20.8%), and pristine P3HT/rGO (similar to 55.1%) composites. Finally, excellent response and recovery behaviors (e.g., similar to 15 s and similar to 42 s, respectively) are also observed.

Automated summary

A facile approach was reported for the fabrication of P3HT/rGO composite films which were used in high-performance VOCs detection with OFET sensors. The synergistic effect of photoirradiation and rGO presence facilitated molecular ordering of P3HT. The composite films showed enhanced sensitivity and charge carrier mobility in detecting VOCs.