Singlet–singlet and singlet–triplet annihilations in structure-regulated porphyrin polymers

Fujitsuka, Mamoru; Satyanarayana, Kamani; Luh, Tien‐Yau; Majima, Tetsuro

doi:10.1016/j.jphotochem.2015.10.011

Cited by 8 publications

(13 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, rapid exciton migration has been observed in helical polyisocyanides 18 with closely-spaced pendant zinc and free-base porphyrins, and ultrafast singlet-singlet and singlet-triplet exciton annihilation have been recorded in porphyrin-pendant cyclobutene and norbornene ring-opened polymers having a variety of Z/E conformations. 19 In our laboratories, we have been particularly interested in the dynamic effects of the aggregation of exciton-carrying species, both in solution and in thin films, with particular emphasis on applications in non-coherent photon upconversion (NCPU) by triplet-triplet annihilation (TTA). 20,21 In particular we have discovered that the efficiencies of TTA in zinc porphyrins, where S2 is the initially-produced upconverted state, are controlled by geometric factors not accounted for in simple Dexter, electron-exchange theory.…”

Section: Introductionmentioning

confidence: 99%

Exciton Dynamics of Photoexcited Pendant Porphyrin Polymers in Solution and in Thin Films

Stevens

Novakovic²,

White³

et al. 2018

J. Phys. Chem. A

View full text Add to dashboard Cite

Several new polymers with rotatable zinc porphyrin pendants have been synthesized and their optical spectroscopic and photophysical properties, including upconversion efficiencies, determined in both fluid solution and thin films. Comparisons made with the β-substituted zinc tetraphenylporphyrin monomers and ZnTPP itself reveal that the yield of triplets resulting from either Q-band or Soret-band excitation of the polymers is surprisingly small. A detailed kinetic analysis of the fluorescence decays and transient triplet absorptions of the substituted monomers and their corresponding polymers reveals that this phenomenon is due to two parallel internal singlet quenching processes assigned to transient intrachain excimer formation. Consequently, the yields of upconverted S 2 fluorescence resulting from Q-band excitation in the degassed polymers are significantly diminished in both fluid solution and thin films. Implications of these results for the design of polymer upconverting systems are discussed.

show abstract

Section: Introductionmentioning

confidence: 99%

Exciton Dynamics of Photoexcited Pendant Porphyrin Polymers in Solution and in Thin Films

Stevens

Novakovic²,

White³

et al. 2018

J. Phys. Chem. A

View full text Add to dashboard Cite

show abstract

“…Comparison between the PLQY values and the ΔE ST of the CDBP, CBP and mCP based exciplex phosphorescence value measured for CDBP:UGH-3 evaporated films at[10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] …”

mentioning

confidence: 99%

Identifying the Factors That Lead to PLQY Enhancement in Diluted TADF Exciplexes Based on Carbazole Donors

2019

View full text Add to dashboard Cite

Here we compare the effects of solid-state dilution on the photophysical and electrical performance of three TADF exciplexes based on carbazole containing donors with a high-performance acceptor PO-T2T. We observe intrinsically different photophysical behaviour between the exciplexes, which is explained by the presence of a heterogeneous distribution of triplet energies in one of the donor molecules arising from a distribution of planar and highly twisted biphenyl bridges. This study of different donors demonstrates that the recently discovered efficiency enhancement of solid-state diluted exciplexes is independent of the separation associated spectral blueshift, with the latter being universal while the former is only found for donors with low structural rigidity. OLEDs produced from these carbazole based exciplexes show decreased electrical performance likely due to the relatively low conductivity of the donors and host, suggesting that functional conductive hosts may, in some cases, be required to translate optical efficiency enhancements into improved electrical performance.

show abstract

“…The stereochemistry of double bonds in 17 has also played an important role on the rate of fast decay attributed to the singlet‐singlet annihilation in the femto second time‐resolved laser flash photolysis, 17 c being the fastest among these substrates. Again, the polymer with a highly stacked structure provided faster annihilation rate …”

Section: Chemical Methodsmentioning

confidence: 98%

Determination of the Orientation of Pendants on Rigid‐Rod Polymers

Luh

Lin

Lai

2020

Chemistry An Asian Journal

View full text Add to dashboard Cite

Bis-norbornene and bis-cyclobutene with different kinds of linkers have been extensively used for the synthesis of double stranded ladderphanes under ruthenium-or molybdenum-catalyzed ring opening metathesis polymerization (ROMP) conditions. The key to the success relies on the selective formation of comb-like polynorbornenes or polycycloubtenes, where pendants are all aligned towards similar direction. This minireview summarizes various methods (chemical methods, spectroscopic means, and nonlinear optical measurements) for determining the comb-like conformations of pendants on these rigid-rod polymers. The approach is based on the proximal relationship between adjacent pendants. Interactions between these adjacent pendants would enable a change in chemical reactivity [a] Prof. T.

show abstract

Singlet–singlet and singlet–triplet annihilations in structure-regulated porphyrin polymers

Cited by 8 publications

References 14 publications

Exciton Dynamics of Photoexcited Pendant Porphyrin Polymers in Solution and in Thin Films

Exciton Dynamics of Photoexcited Pendant Porphyrin Polymers in Solution and in Thin Films

Identifying the Factors That Lead to PLQY Enhancement in Diluted TADF Exciplexes Based on Carbazole Donors

Determination of the Orientation of Pendants on Rigid‐Rod Polymers

Contact Info

Product

Resources

About