Amorphous transition metal-boron ultrafine particles prepared by chemical methods

Corrias, A., Ennas, G., Musinu, A., Marongiu, G., Paschina, G. (1993) Amorphous transition metal-boron ultrafine particles prepared by chemical methods. Chemistry of Materials, 5 (12). pp. 1722-1726. ISSN 0897-4756. (doi:10.1021/cm00036a009) (The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided)

The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided. (Contact us about this Publication)
Official URL
http://dx.doi.org/10.1021/cm00036a009

Abstract

Ultrafine amorphous transition metal-boron (TM-B, TM = Co, Ni, Fe) powders have been prepared, under identical experimental conditions, by chemical reduction of Co2+, Ni2+, and Fe2+ ions with potassium borohydride in aqueous solution. The chemical compositions of the samples are close to TM60B40. The particles have a spheroidal shape with diameters ranging from 10 to 100 nm. X-ray diffraction and transmission electron microscopy investigations show that the Co-B and Ni-B samples are fully amorphous while in a few particles of the Fe-B sample the presence of α-iron microcrystallites are observed. Crystallization of the samples has been investigated by differential scanning calorimetry. Under anaerobic conditions the Co-B sample evolves toward t-Co2B accompanied by a minor quantity of o-Co3B; in the Ni-B and Fe-B samples, crystallization gives rise to a metallic component plus boride phases. A significant decrease of the boride phases and a corresponding increase of the metallic component are obtained in all samples when the thermal treatment is performed in the presence of traces of oxygen.

Item Type: Article
DOI/Identification number: 10.1021/cm00036a009
Subjects: Q Science > QC Physics > QC176.8.N35 Nanoscience, nanotechnology
Divisions: Faculties > Sciences > School of Physical Sciences > Functional Materials Group
Depositing User: Anna Corrias
Date Deposited: 17 Dec 2014 12:24 UTC
Last Modified: 29 May 2019 13:57 UTC
Resource URI: https://kar.kent.ac.uk/id/eprint/46242 (The current URI for this page, for reference purposes)
  • Depositors only (login required):