Competition between two- and three-photon upconversion in Er3+-doped microcrystals

Mukhuti, Kingshuk; Adusumalli, Venkata N. K. B.; Raj, R.; Bansal, Bhavtosh; Mahalingam, Venkataramanan

doi:10.1016/j.jlumin.2020.117542

Cited by 8 publications

(9 citation statements)

References 57 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, the quantum yield of green emission UNCs was much higher than that of blue emission UNCs because generation of blue emission involved three or even four photon transitions with relatively low efficiency, while generation of green emission only required two-photon transition. , When NR-R was utilized in the PET-RAFT polymerization, only negligible monomer conversion was observed (Table , entry 6). This was because photons generated by NR-R could not be efficiently exploited by ZnTPP due to limited overlap of the absorption spectrum of ZnTPP and emission spectrum of NR-R.…”

Section: Resultsmentioning

confidence: 99%

Highly Efficient Near-Infrared Photoinduced Electron/Energy Transfer-Reversible Addition–Fragmentation Chain Transfer Polymerization via the Energy Transfer Upconversion Mechanism

et al. 2022

View full text Add to dashboard Cite

Near-infrared (NIR) light-mediated polymerization has been of particular interest owing to the deep penetration into opaque materials, giving rise to great potential for biomedical applications and solar photochemistry. Photoinduced electron/energy transfer-reversible addition–fragmentation chain transfer (PET-RAFT) polymerization presented unprecedented spatiotemporal control over the controlled radical polymerization process. Herein, we greatly extended the NIR region up to 980 nm by introducing rationally designed upconversion nanocrystals with low toxicity and resistance to photobleaching into PET-RAFT polymerization. Well-defined polymers with predictable molecular weight and narrow dispersity were prepared within a few hours by 980 nm NIR light-regulated PET-RAFT polymerization via the energy transfer upconversion mechanism. The livingness feature of this photopolymerization was confirmed by polymerization kinetics, chain extension experiments, and multiple controlled “on–off” light switching cycles. Furthermore, the polymerizations could be successfully performed using different monomers, in the presence of several visible light-proof barriers (i.e., pork/chicken skin) and even under aerobic conditions, demonstrating the multifold advantages of our approach.

show abstract

Section: Resultsmentioning

confidence: 99%

Highly Efficient Near-Infrared Photoinduced Electron/Energy Transfer-Reversible Addition–Fragmentation Chain Transfer Polymerization via the Energy Transfer Upconversion Mechanism

et al. 2022

View full text Add to dashboard Cite

show abstract

“…The slopes of the linear fitting lines in the low pumping power region are obviously larger than that in the high pumping power region. The slopes derived from the power dependences under the weak pumping, capable of representing the photon numbers involved in an UCL process, are widely investigated [ 50 , 51 , 52 ]. In stark contrast, high pumping slopes are rarely paid attention, although they deliver important information as well.…”

Section: Resultsmentioning

confidence: 99%

Mechanisms of Upconversion Luminescence of Er3+-Doped NaYF4 via 980 and 1530 nm Excitation

et al. 2021

View full text Add to dashboard Cite

To date, the mechanisms of Er3+ upconversion luminescence via 980 and 1530 nm excitation have been extensively investigated; however, based on discussions, they either suffer from the lack of convincing evidence or require elaborated and time-consuming numerical simulations. In this work, the steady-state and time-resolved upconversion luminescence data of Er3+-doped NaYF4 were measured; we therefore investigated the upconversion mechanisms of Er3+ on the basis of the spectroscopic observations and the simplified rate equation modeling. This work provides a relatively simple strategy to reveal the UCL mechanisms of Er3+ upon excitation with various wavelengths, which may also be used in other lanthanide ion-doped systems.

show abstract

“…In our nanoparticle system, the rate-limiting bottleneck for the emission process is the energy-transfer upconversion (ETU). 8 Thus, the emission intensity is directly proportional to the rate of this energy transfer from Yb 3+ to Er 3+ . Hence, eq 8 predicts that the decrease in differential intensity I D should have a B 2 dependence.…”

Section: = * +mentioning

confidence: 99%

“…7 A fundamental step in this anti-Stokes' process from the activator (acceptor) ions via the intra f-shell transitions is the FRET from the sensitizer (donor) ions. 7,8 Herein, we explore the possibility of studying the FRET phenomenon in externally applied magnetic fields. We formulate the problem in simplest possible terms with the donor and acceptor species modeled as spinless hydrogenic systems in their ground state, which acquire their electric dipole moment on account of an external electric field.…”

Section: ■ Introductionmentioning

confidence: 99%

Diamagnetism–Induced Suppression of the Resonance Energy Transfer

Mukhuti

Bansal

2023

J. Phys. Chem. C

Self Cite

View full text Add to dashboard Cite

Long-range energy transport between resonant states of Coulomb-coupled chromophores is important for energy harvesting processes and applications such as upconversion photoluminescence (UCPL) in nanomaterials. While Forster resonance energy transfer (FRET) has been extensively studied, we highlight that perturbing magnetic fields provide an additional handle for characterizing this process. To this end, we extend the quantum electrodynamics calculation for the energy-transfer rate in FRET by including the field dependencies of the transition electric dipole moments of the donor and acceptor species, considered to be spinless hydrogenic entities. We find that the FRET rate is suppressed in an external magnetic field and, to lowest order, shows a quadratic dependence in the magnetic field. Finally, we experimentally study the magnetic field-dependent UCPL intensity in Yb 3+ − Er 3+ -codoped NaGdF 4 nanoparticles. Despite our model's simplicity, we find that the UCPL intensity does show the predicted quadratic scaling.

show abstract

Competition between two- and three-photon upconversion in Er3+-doped microcrystals

Cited by 8 publications

References 57 publications

Highly Efficient Near-Infrared Photoinduced Electron/Energy Transfer-Reversible Addition–Fragmentation Chain Transfer Polymerization via the Energy Transfer Upconversion Mechanism

Highly Efficient Near-Infrared Photoinduced Electron/Energy Transfer-Reversible Addition–Fragmentation Chain Transfer Polymerization via the Energy Transfer Upconversion Mechanism

Mechanisms of Upconversion Luminescence of Er3+-Doped NaYF4 via 980 and 1530 nm Excitation

Diamagnetism–Induced Suppression of the Resonance Energy Transfer

Contact Info

Product

Resources

About