Journalartikel

Autorenliste: Youssef, Heba; Becker, Jonathan; Pietzonka, Clemens; Taydakov, Ilya V.; Kraus, Florian; Müller-Buschbaum, Klaus

Jahr der Veröffentlichung: 2023

Seiten: 1006-1027

Zeitschrift: Chemistry

Bandnummer: 5

Heftnummer: 2

eISSN: 2624-8549

Open Access Status: Gold

DOI Link: https://doi.org/10.3390/chemistry5020069

Verlag: MDPI

Abstract: 
The redox reactions of various lanthanide metals with 3-(4-pyridyl)pyrazole (4-PyPzH) or 3-(3-pyridyl)pyrazole (3-PyPzH) ligands yield the 2D network (2)(infinity)[Eu(4-PyPz)(2)(Py)(2)] containing divalent europium, the 3D frameworks (3)(infinity)[Ln(4-PyPz)(3)] and (3)(infinity)[Ln(3-PyPz)(3)] for trivalent cerium, praseodymium, neodymium, holmium, erbium, and thulium as well as (3)(infinity)[La(4-PyPz)(3)], and the 2D networks (2)(infinity)[Ln(4-PyPz)(3)(Py)] for trivalent cerium and thulium and (2)(infinity)[Ln(2)(4-PyPz)(6)]center dot Py for trivalent ytterbium and lutetium. The 18 lanthanide coordination polymers were synthesized under solvothermal conditions in pyridine (Py), partly acting as a co-ligand for some networks. The compounds exhibit a variety of luminescence properties, including metal-centered 4f-4f/5d-4f emission in the visible and near-infrared spectral range, metal-to-ligand energy transfer, and ligand-centered fluorescence and phosphorescence. The anionic ligands 3-PyPz(-) and 4-PyPz(-) serve as suitable antennas for lanthanide-based luminescence in the visible and near-infrared range through effective sensitization followed by emission through intra-4f transitions of the trivalent thulium, holmium, praseodymium, erbium, and neodymium. (2)(infinity)[Ce(4-PyPz)(3)(Py)], (3)(infinity)[Ce(4-PyPz)(3)], and (3)(infinity)[Ce(3-PyPz)(3)] exhibit strong degrees of reduction in the 5d excited states that differ in intensity compared to the ligand-based emission, resulting in a distinct emission ranging from pink to orange. The direct current magnetic studies show magnetic isolation of the lanthanide centers in the crystal lattice of (3)(infinity)[Ln(3-PyPz)(3)], Ln = Dy, Ho, and Er.

Harvard-Zitierstil: Youssef, H., Becker, J., Pietzonka, C., Taydakov, I., Kraus, F. and Müller-Buschbaum, K. (2023) Divalent Europium, NIR and Variable Emission of Trivalent Tm, Ho, Pr, Er, Nd, and Ce in 3D Frameworks and 2D Networks of Ln-Pyridylpyrazolates, Chemistry, 5(2), pp. 1006-1027. https://doi.org/10.3390/chemistry5020069

APA-Zitierstil: Youssef, H., Becker, J., Pietzonka, C., Taydakov, I., Kraus, F., & Müller-Buschbaum, K. (2023). Divalent Europium, NIR and Variable Emission of Trivalent Tm, Ho, Pr, Er, Nd, and Ce in 3D Frameworks and 2D Networks of Ln-Pyridylpyrazolates. Chemistry. 5(2), 1006-1027. https://doi.org/10.3390/chemistry5020069