Conductometric ppb-level triethylamine sensor based on macroporous WO3-W18O49 heterostructures functionalized with carbon layers and PdO nanoparticles

Effective detection of triethylamine (TEA) is considerable in view of human health and environment. However, both ppb-level detection and rapid response/recovery speed under extreme conditions such as high relative humidity and wide detection ranges remain challenging for TEA gas sensing. Herein, a facile one-spot solvothermal approach is used to synthesize urchin-like WO3-W18O49 heterostructures assisting with glucose modification and PdO functionalization. Benefiting from the hierarchical macroporous structure, synergistic effects, various heterojunctions along with sensitization of PdO, the sensor based on hierarchical WO3-W18O49 urchin with PdO and carbon decorating exhibits appealing TEA sensing performance including rapid response /recovery time (1 s/2 s) to 100 ppm TEA at 325 °C, high selectivity, superior anti-humidity property and extremely low detection limitation (50 ppb), which are much better than previously reported TEA sensors. Our research results open a facile pathway for the development of high-performance gas sensors in terms of real-time and ppb-level detection.