Open AccessInvestigation of upconversion phenomenon in Y1-xLn3+x(BTC)(DMF)2(H2O) and Y0.8-xYb0.2Ln3+x(BTC)(DMF)2(H2O) metal organic frameworks
Author(s) -
Andrius Laurikėnas,
Aivaras Kareiva
Publication year - 2021
Publication title -
chemija
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.16
H-Index - 15
eISSN - 2424-4538
pISSN - 0235-7216
DOI - 10.6001/chemija.v32i2.4434
Subject(s) - photon upconversion , lanthanide , excited state , materials science , photochemistry , metal organic framework , tricarboxylic acid , luminescence , ion , absorption (acoustics) , chemistry , organic chemistry , optoelectronics , physics , adsorption , citric acid cycle , nuclear physics , composite material , enzyme
In this study, Y1-xLn3+x(BTC)(DMF)2(H2O) and Y0.8-xYb0.2Ln3+x(BTC)(DMF)2(H2O) metal organic frameworks (MOFs), which structure included lanthanide ions, Ln3+ (Er3+, Ho3+, Tm3+, Yb3+, Nd3+), suitable for monitoring the upconversion phenomenon, have been synthesised. For this purpose the precursor of the organic moiety, benzene-1,3,5-tricarboxylic acid (BTC), as one of the simplest and very frequently cited carboxylic acid analogues in MOF syntheses, has been selected. By characterising upconversion properties of new MOFs it was determined that only Er3+ can be used as an activator for one centre luminescence upconversion by a ground state absorption/ excited-state absorption (GSA/ESA) mechanism, while with Yb3+, Ho3+, Tm3+ and Nd3+ ions the upconversion was not observed. It was also established that BTC cannot initiate triplet–triplet annihilation upconversion (TTA-UC) as this mechanism sensitizer. Yb3+–Er3+ and Yb3+–Ho3+ ion pairs as a sensitizeractivator were suitable for two-centre luminescence upconversion by a GSA/ excited-state upconversion (GSA/ESU) mechanism. A pair of Yb3+–Tm3+, contrary as shown in the literature review, does not exhibit upconversion properties in the synthesised MOFs.