Rational design of sensitivity enhanced and stability improved TEA gas sensor assembled with Pd nanoparticles-functionalized In2O3 composites

In this work, special triethylamine (TEA) gas sensors based on Pd nanoparticles (NPs)-decorated In2O3 microstructures with different Pd amount have been successfully fabricated. The optimal sensor based on 3 wt% Pd-loaded In2O3 shows higher gas response compared with other content of Pd wt% and exhibits the highest response of 47.56 when exposed to 50 ppm TEA gas. Furthermore, 3 wt% Pd NPs-In2O3 sensor not only possesses superior response and recovery properties of 4 s and 17 s under 50 ppm TEA gas, respectively, but also displays outstanding selectivity to TEA gas at the existence of other interfering gases. Based on the model of depletion layer, the possible gas sensing mechanism are studied and the results show that, the synergistic effect between the sensitization exerted by Pd nanoparticles and structural defects may be responsible for the remarkably enhanced TEA sensing performance. Considering the superiority including low cost, simple structure, and facile fabrication, 3 wt% Pd NPs-In2O3 microstructures are promising for high-performance TEA sensing applications.