Phonon-assisted molecular upconversion in a holmium(<scp>iii</scp>)-based molecular cluster-aggregate

Gálico, Diogo A.; Ramdani, Rayan; Murugesu, Muralee

doi:10.1039/d2nr02643k

Cited by 18 publications

(19 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…S1-S3 †). [58][59][60][61] The powder X-ray diffraction pattern (Fig. S2 †) is in agreement with the simulated one, indicating that we obtained the desired materials with crystalline purity.…”

Section: Resultssupporting

confidence: 83%

“…This indicates the presence of a very short decay time for one of the Tb III occupied sites and corroborates with the occurrence of a strong Tb III → Eu III ET, as previously demonstrated for the {Ln 20 } class of compounds. [58][59][60][61] On the other hand, Eu III ions exhibit a more straightforward decay dynamics. It should be noted that at approximately 600 µs, the decay rate of Tb III ions became slower than the observed for Eu III ions.…”

Section: Resultsmentioning

confidence: 99%

“…{Eu 5 Tb 15 } MCAs were synthesized following a previously reported procedure with minor adaptations (Scheme 1): 58–61…”

Section: Methodsmentioning

confidence: 99%

“…Synthesis {Eu 5 Tb 15 } MCAs were synthesized following a previously reported procedure with minor adaptations (Scheme 1): [58][59][60][61] 0.25 mmol Eu(NO 3 ) 3 •6H 2 O (107 mg), 0.75 mmol Tb (NO 3 ) 3 •6H 2 O (339.8 mg), and 6-chloro-2-pyridinol (0.130 g, 1.00 mmol) were added to 20 mL of MeOH/MeCN (1 : 1), followed by the addition of triethylamine (0.139 mL, 1.00 mmol). After 12 hours stirring, the resulting solution was filtered and left undisturbed in an open vial for solvent evaporation at room temperature.…”

Section: Methodsmentioning

confidence: 99%

See 3 more Smart Citations

Boosting the sensitivity with time-gated luminescence thermometry using a nanosized molecular cluster aggregate

Gálico

Murugesu

2023

Nanoscale

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Resultssupporting

confidence: 83%

Section: Resultsmentioning

confidence: 99%

“…{Eu 5 Tb 15 } MCAs were synthesized following a previously reported procedure with minor adaptations (Scheme 1): 58–61…”

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

Boosting the sensitivity with time-gated luminescence thermometry using a nanosized molecular cluster aggregate

Gálico

Murugesu

2023

Nanoscale

Self Cite

View full text Add to dashboard Cite

show abstract

“…However, in recent years, our research group has been focused on developing heterometallic MCAs for various applications, unlocking the vast potential of this class of compounds. 79,81,92–96…”

Section: Lanthanide-based Molecular Cluster-aggregatesmentioning

confidence: 99%

Lanthanide molecular cluster-aggregates as the next generation of optical materials

2023

Self Cite

View full text Add to dashboard Cite

show abstract

Solution‐State Cooperative Luminescence Upconversion in Molecular Ytterbium Dimers

Soro

Knighton

Avecilla

et al. 2022

Advanced Optical Materials

View full text Add to dashboard Cite

anti-Stokes emission, UC is a process of choice for bio-analytical applications, removing spurious signals originating from autofluorescence of the samples and light scattering. Consequently, UC has found many applications such as in microscopy and photodynamic therapy, [2] remote cellular activation, [3] or bioassays. [4,5] However, these processes are typically observed in solid-state materials [6] or nanoparticles, [7] but a seminal example of energy transfer UC (ETU) at the molecular scale was reported by Piguet and co-workers in 2011, which consisted of a triply stranded Cr III -Er III -Cr III helicate. [8,9] In the subsequent years this has been expanded to encompass a range of discrete upconverting systems, operating by excited state absorption (ESA), [10][11][12] energy transfer UC, or cooperative sensitizaton (CS). [15][16][17][18] At the molecular scale, much attention must be paid to minimize quenching due to the increased prevalence of nonradiative de-excitation processes from molecules in solution, primarily through OH, NH, and CH oscillators in the first or second coordination sphere. [20][21][22] This is achieved by using sterically encumbering ligand systems, [23] deuteration of the ligand scaffold, [16] or using perdeuterated solvents. [16,24,25] One key impediment in the development of new molecular UC devices is the typical requirement to prepare heterometallic polyads, as is the case with CS systems comprising two or more Yb III sensitizers around Tb III or Ru II acceptors (Figure 1a). [17,26] This approach, despite its effectiveness, is onerous due to the similar chemical reactivity between lanthanides, [27,28] as is the case for mixed Yb/Tb systems, which constrains the synthetic accessibility. [15,16] Inspired by the pioneering work by Auzel [29] on solid-state materials, [30,31] we reported the first example of solution-state molecular cooperative luminescence (CL) using a Yb 9 cluster. [32] This entails double excitation of two proximate Yb III ions at 980 nm which produces emission from a virtual excited state at 503 nm via a two-photon process (Figure 1b). While it is a key tenet of UC processes that the efficiency of UC is improved using more donor ions, there also remains the possibility of concentration quenching, which has been observed in nanoparticles. [33,34] Furthermore, the two-photon power dependence of the UC observed in homo-nonanuclear Yb 9 clusters supports the accepted mechanism of the requirement of only two proximate Yb III ions. Conclusive confirmation of this dinuclear mechanism can only occur through removal of the extraneous Yb III donors to its fundamental form in a dimeric Yb 2 system (lex parsimoniae). This strategy is not feasible in either Two homometallic ytterbium dimers are prepared and their solution-state photoluminescence and upconversion properties are investigated. Both complexes exhibit two-photon cooperative luminescence upconversion in the visible region (λ em ≈ 510 nm) upon excitation into the near-infrared Yb 2 F 5/2 ← 2 F 7/2 absorption band at 98...

show abstract

Phonon-assisted molecular upconversion in a holmium(iii)-based molecular cluster-aggregate

Abstract: Upconversion (UC) is a fascinating process in which higher energy photons can be emitted from the excitation by lower energy photons. A current challenge remains in downscaling and effectively achieving...

Cited by 18 publications

References 56 publications

Boosting the sensitivity with time-gated luminescence thermometry using a nanosized molecular cluster aggregate

Boosting the sensitivity with time-gated luminescence thermometry using a nanosized molecular cluster aggregate

Lanthanide molecular cluster-aggregates as the next generation of optical materials

Solution‐State Cooperative Luminescence Upconversion in Molecular Ytterbium Dimers

Contact Info

Product

Resources

About