Cargando…

Heterostructural Mixed Oxides Prepared via ZnAlLa LDH or ex-ZnAl LDH Precursors—Effect of La Content and Its Incorporation Route

The effect of La content and its incorporation route on physicochemical properties of ZnO/Zn(Al,La)(2)O(4) or La(2)O(3)–ZnO/ZnAl(2)O(4) mixed oxides with a spinel structure obtained from ZnAlLa Layered double hydroxides (LDHs) or ex-ZnAl LDH materials was investigated. The heterostructural nanocompo...

Descripción completa

Detalles Bibliográficos
Autores principales: Antoniak-Jurak, Katarzyna, Kowalik, Paweł, Próchniak, Wiesław, Bicki, Robert, Słowik, Grzegorz
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8074398/
https://www.ncbi.nlm.nih.gov/pubmed/33924164
http://dx.doi.org/10.3390/ma14082082
_version_ 1783684346080657408
author Antoniak-Jurak, Katarzyna
Kowalik, Paweł
Próchniak, Wiesław
Bicki, Robert
Słowik, Grzegorz
author_facet Antoniak-Jurak, Katarzyna
Kowalik, Paweł
Próchniak, Wiesław
Bicki, Robert
Słowik, Grzegorz
author_sort Antoniak-Jurak, Katarzyna
collection PubMed
description The effect of La content and its incorporation route on physicochemical properties of ZnO/Zn(Al,La)(2)O(4) or La(2)O(3)–ZnO/ZnAl(2)O(4) mixed oxides with a spinel structure obtained from ZnAlLa Layered double hydroxides (LDHs) or ex-ZnAl LDH materials was investigated. The heterostructural nanocomposites with the similar Zn/Al molar ratio and varied La content were prepared by two techniques: via co-precipitation and thermal treatment of ZnAlLa LDHs at 500 °C or via incipient wetness impregnation of ex-ZnAl LDHs with aqueous solutions of lanthanum nitrate and subsequent thermal treatment. The obtained series of materials were characterized by the following techniques: X-ray fluorescence (XRF), N(2) adsorption (BET), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis with evolved gas analysis (TG/DTG/EGA), scanning transmission electron microscopy (STEM) energy-dispersive X-ray spectroscopy (EDS), high-resolution transmission electron microscopy (HRTEM) and Fourier-transform infrared spectroscopy (FFT). The evaluation of activity toward the high-temperature water gas shift (HT-WGS) within the temperature range of 350–420 °C was carried out on the basis of rate constant measurements in the kinetic mode using a differential reactor. The co-precipitation technique allowed for a better distribution of La in bulk and on the spinel surface than in case of lanthanum incorporation via impregnation. ZnO/Zn(Al,La)(2)O(4) or La(2)O(3)–ZnO/ZnAl(2)O(4) mixed oxides were characterized by moderate activity in the HT-WGS reaction. The results reveal that introduction of lanthanum oxide over 2.4–2.8 wt% induces the phase separation of the ZnAl(2)O(4) spinel, forming ZnO on the ZnAl(2)O(4) spinel surface.
format Online
Article
Text
id pubmed-8074398
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher MDPI
record_format MEDLINE/PubMed
spelling pubmed-80743982021-04-27 Heterostructural Mixed Oxides Prepared via ZnAlLa LDH or ex-ZnAl LDH Precursors—Effect of La Content and Its Incorporation Route Antoniak-Jurak, Katarzyna Kowalik, Paweł Próchniak, Wiesław Bicki, Robert Słowik, Grzegorz Materials (Basel) Article The effect of La content and its incorporation route on physicochemical properties of ZnO/Zn(Al,La)(2)O(4) or La(2)O(3)–ZnO/ZnAl(2)O(4) mixed oxides with a spinel structure obtained from ZnAlLa Layered double hydroxides (LDHs) or ex-ZnAl LDH materials was investigated. The heterostructural nanocomposites with the similar Zn/Al molar ratio and varied La content were prepared by two techniques: via co-precipitation and thermal treatment of ZnAlLa LDHs at 500 °C or via incipient wetness impregnation of ex-ZnAl LDHs with aqueous solutions of lanthanum nitrate and subsequent thermal treatment. The obtained series of materials were characterized by the following techniques: X-ray fluorescence (XRF), N(2) adsorption (BET), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis with evolved gas analysis (TG/DTG/EGA), scanning transmission electron microscopy (STEM) energy-dispersive X-ray spectroscopy (EDS), high-resolution transmission electron microscopy (HRTEM) and Fourier-transform infrared spectroscopy (FFT). The evaluation of activity toward the high-temperature water gas shift (HT-WGS) within the temperature range of 350–420 °C was carried out on the basis of rate constant measurements in the kinetic mode using a differential reactor. The co-precipitation technique allowed for a better distribution of La in bulk and on the spinel surface than in case of lanthanum incorporation via impregnation. ZnO/Zn(Al,La)(2)O(4) or La(2)O(3)–ZnO/ZnAl(2)O(4) mixed oxides were characterized by moderate activity in the HT-WGS reaction. The results reveal that introduction of lanthanum oxide over 2.4–2.8 wt% induces the phase separation of the ZnAl(2)O(4) spinel, forming ZnO on the ZnAl(2)O(4) spinel surface. MDPI 2021-04-20 /pmc/articles/PMC8074398/ /pubmed/33924164 http://dx.doi.org/10.3390/ma14082082 Text en © 2021 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Antoniak-Jurak, Katarzyna
Kowalik, Paweł
Próchniak, Wiesław
Bicki, Robert
Słowik, Grzegorz
Heterostructural Mixed Oxides Prepared via ZnAlLa LDH or ex-ZnAl LDH Precursors—Effect of La Content and Its Incorporation Route
title Heterostructural Mixed Oxides Prepared via ZnAlLa LDH or ex-ZnAl LDH Precursors—Effect of La Content and Its Incorporation Route
title_full Heterostructural Mixed Oxides Prepared via ZnAlLa LDH or ex-ZnAl LDH Precursors—Effect of La Content and Its Incorporation Route
title_fullStr Heterostructural Mixed Oxides Prepared via ZnAlLa LDH or ex-ZnAl LDH Precursors—Effect of La Content and Its Incorporation Route
title_full_unstemmed Heterostructural Mixed Oxides Prepared via ZnAlLa LDH or ex-ZnAl LDH Precursors—Effect of La Content and Its Incorporation Route
title_short Heterostructural Mixed Oxides Prepared via ZnAlLa LDH or ex-ZnAl LDH Precursors—Effect of La Content and Its Incorporation Route
title_sort heterostructural mixed oxides prepared via znalla ldh or ex-znal ldh precursors—effect of la content and its incorporation route
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8074398/
https://www.ncbi.nlm.nih.gov/pubmed/33924164
http://dx.doi.org/10.3390/ma14082082
work_keys_str_mv AT antoniakjurakkatarzyna heterostructuralmixedoxidespreparedviaznallaldhorexznalldhprecursorseffectoflacontentanditsincorporationroute
AT kowalikpaweł heterostructuralmixedoxidespreparedviaznallaldhorexznalldhprecursorseffectoflacontentanditsincorporationroute
AT prochniakwiesław heterostructuralmixedoxidespreparedviaznallaldhorexznalldhprecursorseffectoflacontentanditsincorporationroute
AT bickirobert heterostructuralmixedoxidespreparedviaznallaldhorexznalldhprecursorseffectoflacontentanditsincorporationroute
AT słowikgrzegorz heterostructuralmixedoxidespreparedviaznallaldhorexznalldhprecursorseffectoflacontentanditsincorporationroute