Synthesis and Characterization of MWCNT-COOH/Fe<sub>3</sub>O<sub>4</sub> and CNT-COOH/Fe<sub>3</sub>O<sub>4</sub>/NiO Nanocomposites: Assessment of Adsorption and Photocatalytic Performance
Adina Stegarescu,
Humberto Cabrera,
Hanna Budasheva,
Maria-Loredana Soran,
Ildiko Lung,
Francesca Limosani,
Dorota Korte,
Matteo Amati,
Gheorghe Borodi,
Irina Kacso,
Ocsana Opriş,
Monica Dan,
Stefano Bellucci
Affiliations
Adina Stegarescu
National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania
Humberto Cabrera
Optics Lab, STI Unit, The Abdus Salam International Centre for Theoretical Physics, Costiera 11, 34151 Trieste, Italy
Hanna Budasheva
Laboratory for Environmental and Life Sciences, University of Nova Gorica, Vipavska 13, SI-5000 Nova Gorica, Slovenia
Maria-Loredana Soran
National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania
Ildiko Lung
National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania
Francesca Limosani
INFN-National Laboratories of Frascati, Via Enrico Fermi 54, 00044 Frascati, Italy
Dorota Korte
Laboratory for Environmental and Life Sciences, University of Nova Gorica, Vipavska 13, SI-5000 Nova Gorica, Slovenia
Matteo Amati
Spectroscopy, Photoemission and Dynamics, Elettra—Sincrotrone Trieste S.C.p.A. S.S. 14, km 163.5 in Area Science Park, Basovizza, 34149 Trieste, Italy
Gheorghe Borodi
National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania
Irina Kacso
National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania
Ocsana Opriş
National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania
Monica Dan
National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca, Romania
Stefano Bellucci
INFN-National Laboratories of Frascati, Via Enrico Fermi 54, 00044 Frascati, Italy
In this study the adsorption and photodegradation capabilities of modified multi-walled carbon nanotubes (MWCNTs), using tartrazine as a model pollutant, is demonstrated. MWCNT-COOH/Fe3O4 and MWCNT-COOH/Fe3O4/NiO nanocomposites were prepared by precipitation of metal oxides in the presence of MWCNTs. Their properties were examined by X-ray diffraction in powder (XRD), Fourier-transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman spectroscopy, synchrotron-based Scanning PhotoElectron Microscopy (SPEM), and Brunauer-Emmett-Teller (BET) analysis. It was found that the optimal adsorption conditions were pH 4 for MWCNT-COOH/Fe3O4 and pH 3 for MWCNT-COOH/Fe3O4/NiO, temperature 25 °C, adsorbent dose 1 g L−1, initial concentration of tartrazine 5 mg L−1 for MWCNT-COOH/Fe3O4 and 10 mg L−1 for MWCNT-COOH/Fe3O4/NiO and contact time 5 min for MWCNT-COOH/Fe3O4/NiO and 15 min for MWCNT-COOH/Fe3O4. Moreover, the predominant degradation process was elucidated simultaneously, with and without simulated sunlight irradiation, using thermal lens spectrometry (TLS) and UV–Vis absorption spectrophotometry. The results indicated the prevalence of the photodegradation mechanism over adsorption from the beginning of the degradation process.
