A high-efficient amperometric hydrazine sensor based on novel electrospun CoFe2O4 spinel nanofibers

Heterojunction Fe2O3 nanoparticles (NPs), NiFe2O4 nanofibers (NFs), and CoFe2O4 NFs were synthesized by electrospinning and the subsequent thermal treatment processes. Characterization results indeed display the three-dimensional net-like textural structures of these as-electrospun spinel-type MFe2O4 NFs. The MFe2O4 NFs-based film configurations possess abundant micro/meso/macropores on their surface. These structures could afford more accessible transport channels for effective reduction of the mass transport resistance and improvement of the density of exposed catalytic active sites. All these advantages are responsible for the enhanced electro-catalytic performance of these MFe2O4 NFs in hydrazine oxidation. When used for hydrazine detection, CoFe2O4 NFs show the best catalytic efficiency. For example, the CoFe2O4 NFs possess a large sensitivity of 1327 mu A cm(-2) (mmol L-1)(-1) in the linear range of 0.01 to 0.1 mmol L-1 and 503 mu A cm(-2) (mmol L-1)(-1) in the linear range of 0.1 toll mmol L-1, a response time of shorter than 3 s, good reproducibility and remarkable long-term stability. The superior catalytic efficiency, excellent stability, low cost, and ease of fabrication render CoFe2O4 NFs very promising materials in developing an electrochemical device that directly detects hydrazine. (C) 2015 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.