Gold Embedded Maghemite Hybrid Nanowires and Their Gas Sensing Properties

Autor:	Lijie Zhang, Shun Wang, Wei-Ming Zhang, Keqin Yang, Kai-Min Li, Qing Chen, Na-Mei Li
Rok vydání:	2015
Předmět:	Thermogravimetry Materials science Colloidal gold Scanning electron microscope Transmission electron microscopy Nano engineering Nanowire Maghemite Nanoparticle General Materials Science Nanotechnology engineering.material
Zdroj:	ACS Applied Materials & Interfaces. 7:10534-10540
ISSN:	1944-8252 1944-8244
DOI:	10.1021/acsami.5b02087
Popis:	Well-defined gold embedded maghemite hybrid nanowires are synthesized, and their structures are fully characterized. They are composed of porous γ-Fe2O3 shells and embedded gold nanoparticles (3-10 nm), which is novel and very different from the conventional "surface decoration" configuration. These hybrid nanowires are produced by the de-alloying of Au-Fe alloy nanowires and subsequent heat treatment. The reaction mechanism is proposed and validated. The results of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and thermogravimetry techniques prove consistently that the Fe composition of Au-Fe alloy nanowires change to γ-FeOOH first and then to γ-Fe2O3. The embedded gold particles are help to enhance the gas response properties of the hybrid nanowires, which is attributed to the nano open-circuit Schottky junctions between γ-Fe2O3 and the Au nanoparticles. The gas sensing experiment data with high repeatability demonstrate that these hybrid nanowires are excellent sensing materials, especially for ethanol, and have shown both high selectivity and high sensitivity.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c6f58b480a1563ef9f4038aa940fc066 https://doi.org/10.1021/acsami.5b02087 Zobrazit plný text záznamu