Cu-Loaded Polyaniline-Coated MoO3 Nanowire Nanohybrids for High-Sensitivity NH3 Sensing at Room Temperature

The Cu-loaded polyaniline-coated MoO3 nanowire ternary nanohybrids were successfully prepared by the solution heat method and in situ oxidation polymerization method for traces of ammonia (NH3) detection at room temperature. The prepared ternary nanohybrids were placed on the fork finger electrode of the alumina substrate by a spin coating method. The gas sensitivity of the devices to NH3 was evaluated by the static method at room temperature. The results showed that the sensor based on the Cu-3-PMN-20 ternary nanohybrid (doping 20 wt % MoO3 nanowires and loaded 3 wt % nano Cu in PANI) exhibited the best sensitivity (17.11), which was 6 times higher than that of pure PANI (2.86) to 100 ppm (parts-per-million) NH3. Meanwhile, the sensor based on Cu-3-PMN-20 ternary hybrid also showed an excellent detection limit [20 ppb(parts-per-billion)], fast response-recovery time (41/179 s), outstanding selectivity, reliable stability, and acceptable moisture resistance. Therefore, the Cu-3-PMN-20 ternary hybrid was expected to be a strong competitor in the field of NH3 sensing at room temperature.