Porous LaFeO3 microspheres decorated with Au nanoparticles for superior formaldehyde gas-sensing performances

Abstract

Formaldehyde is one of the most serious pollutants of volatile organic compounds in indoor environment. The monitoring of formaldehyde concentration of the indoor environment has become an urgent issue in modern society. In this paper, a facile wet-chemical method was used to prepare the catalytic Au nanoparticle-functionalized LaFeO3 porous microspheres with high formaldehyde (HCHO)-sensing performances. The Au/LaFeO3 nanocomposites were characterized by several common testing methods, such as XRD, SEM, EDS, TEM, and XPS. The results showed that Au nanoparticles were uniformly attached to the surface of porous LaFeO3 microspheres. And the gas-sensing experiments showed that Au nanoparticle-functionalized porous LaFeO3 microspheres showed high response even at low concentration (1 ppm), good selectivity, good reproducibility, and ultrafast response (2 s) and recovery (9 s) to formaldehyde. Therefore, the successful preparation of Au/LaFeO3 nanocomposites is expected to be used in the rapid detection of formaldehyde gas.