Premium
Low Temperature Synthesis of Needle‐like α‐ FeOOH and Their Conversion into α‐ Fe 2 O 3 Nanorods for Humidity Sensing Application
Author(s) -
Adhyapak Parag V.,
Mulik Uttam P.,
Amalnerkar Dinesh P.,
Mulla Imtiaz S.
Publication year - 2013
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/jace.12189
Subject(s) - raman spectroscopy , nanorod , scanning electron microscope , analytical chemistry (journal) , chemical engineering , relative humidity , spectroscopy , materials science , humidity , chemistry , nuclear chemistry , nanotechnology , chromatography , composite material , physics , engineering , quantum mechanics , optics , thermodynamics
In this study, we report template and surfactant‐free, low temperature (70°C) synthesis of needle‐like α‐FeOOH and its conversion at 400°C into α‐Fe 2 O 3 nanorods using Fe(+2) and Fe(+3) chlorides and urea as a hydrolysis‐controlling agent. The isolated needle‐like α‐FeOOH indicates asparagus‐type growth pattern having length ca. 600 nm with 80 nm diameter at base and apex diameter of around 10 nm. The sample on heating (α‐Fe 2 O 3 ) shows nanorod‐like morphology. The samples were characterized using various physicochemical characterization techniques such as XRD , Raman spectroscopy, UV ‐Vis spectroscopy, particle size distribution analysis, Field Emission Scanning Electron Microscopy ( FE ‐ SEM ), and humidity sensing performance. The humidity sensing behavior of both α‐FeOOH and α‐Fe 2 O 3 was studied. The α‐FeOOH shows quicker (10 s) and higher response toward change in humidity from 20% RH to 90% RH as compared with α‐Fe 2 O 3 (60 s). Their typical morphology and crystalline structure plays an important role in humidity sensing behavior.