Synthesis of porous α-Fe2O3 microrods via in situ decomposition of FeC2O4 precursor for ultra-fast responding and recovering ethanol gas sensor

Porous α-Fe2O3 microrods with net-worked nanostructure were synthesized by a simple low-temperature hydrothermal method that using the FeC2O4·2H2O as sacrifice template. X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Brunauer Emmett Teller N2 adsorption-desorption analysis were used to characterize the morphology and structure of as-prepared products. Furthermore, the gas sensing properties of the porous α-Fe2O3 microrods were evaluated and compared with compact α-Fe2O3 nanoparticles. All results reveal that the as-prepared porous α-Fe2O3 microrods exhibit higher response, ultra-fast response/recovery characteristics and superior long-term stability than compact α-Fe2O3 nanoparticles. The enhancement of gas sensing properties is attributed to the larger specific surface area, larger pore size and through-pore structure. Our present work may explore a possibility to prepare real-time monitoring gas sensors material which has ultra-fast responding and recovering behaviors.