Sensing platform of PdO-ZnO-In2O3 nanofibers using MOF templated catalysts for triethylamine detection

New sensing platform of PdO-ZnO-In2O3 nanofibers were prepared by a distinctive catalyst loading method (Pd@ZIF-8). The results of TEM show that Pd nanoparticles is about 2 nm in Pd@ZIF-8 and XPS results demonstrate that it finally exists in the form of ultra-small PdO nanoparticles in composite nanofibers. Pure In2O3 and ZnO-In2O3 nanofibers were subjected to comparative gas-sensing investigation to verify the superiority of the PdO-ZnO-In2O3 nanofibers. The results suggest that sensors fabricated on PdO-ZnO-In2O3 nanofibers show enhanced triethylamine response (Ra/Rg = 386 to 100 ppm triethylamine), great selectivity and excellent response/recover speed (1 s/740 s) at 250℃. Furthermore, the loading amount of PdO is 0.2 mol% which is lower than that of the traditional method. The distinguished triethylamine gas sensing performance of PdO-ZnO-In2O3 nanofibers could be mainly due to the maximizing the depletion effects of ultra-small PdO catalysts, and the heterojunctions between PdO (ZnO) and In2O3. This work not only proves that PdO-ZnO-In2O3 nanofibers have great potential for triethylamine detection, but also indicates that using ZIF-8 template to design high-performance sensitive materials is an effective method.