Luminescent spherical particles of lanthanide-based infinite coordination polymers with tailorable sizes

• Published in: CrystEngComm Vol. 22; no. 14; pp. 2439 - 2446
• Main Authors: Arroyos, Guilherme, Frem, Regina C. G
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 14.04.2020
• Subjects: Coordination polymers; Diffraction patterns; Luminescence; Metal ions; NMR; Nuclear magnetic resonance; Optical properties; Photoluminescence; Pyrazole; Rare earth elements; X ray powder diffraction
• ISSN: 1466-8033; 1466-8033
• DOI: 10.1039/d0ce00155d

Infinite coordination polymers (ICPs) are compounds usually obtained as spherical particles exhibiting amorphous phases in powder X-ray diffraction patterns. In the present work, we report an ICP system based on rare-earth ions with pyrazole-3,5-dicarboxylate as a linker and malonate as a coordination modulator. The compounds exhibit a 2D MOF structure. Three different synthetic routes were used, namely microwave-assisted, solvothermal and gel diffusion. The syntheses yield single-phase spherical particles, which were characterized by PXRD, 1 H NMR, CHN, FTIR, TGA, SEM and TEM. Photoluminescence spectroscopy was carried out to study the luminescence properties of the Eu 3+ and Tb 3+ -based samples. With the different-sized particles obtained, we could elucidate the intricate microstructure of the spheres and propose a reason behind the observed amorphous phases in the PXRD patterns. The influence of three different synthetic routes on the size and morphology of luminescent lanthanide-based infinite coordination polymers was investigated.