| Autor: |
Rusu MM; Department of Physics and Chemistry, Technical University of Cluj-Napoca, 400114 Cluj-Napoca, Romania., Fort CI; Laboratory of Advanced Materials and Applied Technologies, Institute of Research-Development-Innovation in Applied Natural Sciences, 'Babes-Bolyai' University, Fantanele 30, 400294 Cluj-Napoca, Romania.; Department of Chemical Engineering, Faculty of Chemistry and Chemical Engineering, 'Babes-Bolyai' University, Arany Janos 11, 400028 Cluj-Napoca, Romania., Vulpoi A; Nanostructured Materials and Bio-Nano-Interfaces Center, Institute of Interdisciplinary Research in Bio-Nano-Sciences, 'Babes-Bolyai' University, T. Laurean 42, 400271 Cluj-Napoca, Romania., Barbu-Tudoran L; Electron Microscopy Laboratory 'Prof. C. Craciun', Faculty of Biology and Geology, 'Babes-Bolyai' University, Clinicilor Str. 5-7, 400006 Cluj-Napoca, Romania.; Electron Microscopy Integrated Laboratory, National Institute for Research and Development of Isotopic and Molecular Technologies, 400293 Cluj-Napoca, Romania., Baia M; Laboratory of Advanced Materials and Applied Technologies, Institute of Research-Development-Innovation in Applied Natural Sciences, 'Babes-Bolyai' University, Fantanele 30, 400294 Cluj-Napoca, Romania.; Department of Biomolecular Physics, Faculty of Physics, 'Babes-Bolyai' University, M. Kogalniceanu 1, 400084 Cluj-Napoca, Romania., Cotet LC; Laboratory of Advanced Materials and Applied Technologies, Institute of Research-Development-Innovation in Applied Natural Sciences, 'Babes-Bolyai' University, Fantanele 30, 400294 Cluj-Napoca, Romania.; Department of Chemical Engineering, Faculty of Chemistry and Chemical Engineering, 'Babes-Bolyai' University, Arany Janos 11, 400028 Cluj-Napoca, Romania., Baia L; Laboratory of Advanced Materials and Applied Technologies, Institute of Research-Development-Innovation in Applied Natural Sciences, 'Babes-Bolyai' University, Fantanele 30, 400294 Cluj-Napoca, Romania.; Nanostructured Materials and Bio-Nano-Interfaces Center, Institute of Interdisciplinary Research in Bio-Nano-Sciences, 'Babes-Bolyai' University, T. Laurean 42, 400271 Cluj-Napoca, Romania.; Department of Condensed Matter Physics and Advanced Technologies, Faculty of Physics, 'Babes-Bolyai' University, M. Kogalniceanu 1, 400084 Cluj-Napoca, Romania. |
| Abstrakt: |
Multifunctional materials based on carbon xerogel (CX) with embedded bismuth (Bi) and iron (Fe) nanoparticles are tested for ultrasensitive amperometric detection of lead cation (Pb 2+ ) and hydrogen peroxide (H 2 O 2 ). The prepared CXBiFe-T nanocomposites were annealed at different pyrolysis temperatures (T, between 600 and 1050 °C) and characterized by X-ray diffraction (XRD), Raman spectroscopy, N 2 adsorption, dynamic light scattering (DLS), and electron microscopies (SEM/EDX and TEM). Electrochemical impedance spectroscopy (EIS) and square wave anodic stripping voltammetry (SWV) performed at glassy carbon (GC) electrodes modified with chitosan (Chi)-CXBiFe-T evidenced that GC/Chi-CXBiFe-1050 electrodes exhibit excellent analytical behavior for Pb 2+ and H 2 O 2 amperometric detection: high sensitivity for Pb 2+ (9.2·10 5 µA/µM) and outstanding limits of detection (97 fM, signal-to-noise ratio 3) for Pb 2+ , and remarkable for H 2 O 2 (2.51 µM). The notable improvements were found to be favored by the increase in pyrolysis temperature. Multi-scale parameters such as (i) graphitization, densification of carbon support, and oxide nanoparticle reduction and purification were considered key aspects in the correlation between material properties and electrochemical response, followed by other effects such as (ii) average nanoparticle and Voronoi domain dimensions and (iii) average CXBiFe-T aggregate dimension. |
