Facile synthesis of 3D flowerlike α-FeOOH architectures and their conversion into mesoporous α-Fe2O3 for gas-sensing application

We reported a facile and efficient solution-based route to prepare novel flowerlike alpha-FeOOH architectures without any template or surfactant Scanning electron microscope (SEM) images reveal that leaflike nanosheets with a thickness about 40 nm assembled into flowerlike superstructures On the basis of time-dependent experiments a multistage reaction mechanism for the formation of the flowerlike alpha-FeOOH was proposed After heat treatment the flowerlike alpha-FeOOH could be converted into corresponding mesoporous alpha-Fe2O3 Transmission electron microscopy (TEM) images and porosity analysis showed that the nanosheets have porous walls with a pore size of about 7 nm As a demonstration of potential application for gas-sensing materials the mesoporous alpha-Fe2O3 nanostructures exhibited short response/recovery time within 5/10 s and low response concentration of 1 ppm toward acetone vapors Large specific surface area and mesoporous structure should be beneficial for the sensing properties of alpha-Fe2O3 (C) 2010 Elsevier Masson SAS All rights reserved