Hexagonal bi-pyramid α-Fe2O3 microcrystals: Unusual formation, characterization and application for gas sensing

A hydrothermal strategy is developed to realize the controllable synthesis of hexagonal bipyramid alpha-Fe2O3 microcrystals (HB-alpha-Fe2O3 MCs) using FeOOH nanorods as precursor. Based on the SEM, TEM and BET analysis, such HB-alpha-Fe2O3 MCs have a perfect hexagonal bi-pyramid structure with the specific surface area of 78.2 m(2) g(-1). Formation mechanism of HB-alpha-Fe2O3 MCs is tentatively proposed by comparative structure-evolution investigations. By virtue of their structural advantages, HB-alpha-Fe2O3 MCs served as a gas sensor exhibit remarkable sensor response, selectivity, and response/recovery towards ethanol gas. All these impressive performances indicate their appealing application in advanced gas sensors. This well-controllable hexagonal bipyramid microcrystals are opening up an unusual way to fabricate advanced electrodes for sensor, catalyst, and energy-related applications. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

A hydrothermal strategy was developed to synthesize hexagonal bipyramid alpha-Fe2O3 microcrystals (HB-alpha-Fe2O3 MCs) with FeOOH nanorods precursor, exhibiting perfect structure and remarkable sensor response, selectivity, and response/recovery towards ethanol gas, indicating their potential in advanced gas sensors. This controllable hexagonal bipyramid microcrystals offer a new approach for fabricating electrodes for sensor, catalyst, and energy-related applications.