Enhancing the intermolecular singlet fission efficiency by controlling the self-assembly of amphipathic tetracene derivatives in aqueous solution

Abstract

Introduction of the carboxyl group onto tetracene can change the singlet fission mechanism and increase the singlet fission yield in its nanoparticles.

Altering singlet fission pathways in perylene-dimers; perylene-diimide versus perylene-monoimide

“…Instead, either triplet-triplet annihilation (TTA), by which the electronic ground state is recovered, takes over, or up-conversion via geminate triplet-triplet recombination (G-TTA-UC) occurs to yield (S 1 S 0 ). 33,34,[35][36][37][38][39][40][41][42]43 Recently, several families of molecular building blocks have been demonstrated to be SF-active: these include first and foremost linear acenes 12,[44][45][46][47][48][49][50][51][52] such as tetracene and pentacene, followed by carotenoids, [53][54][55][56][57][58][59] diketopyrrolopyrroles, 26,32,[60][61][62][63][64][65][66][67] and rylenes 31,[68][69][70][71][72][73][74][75][76] such as perylene-and terrylene-diimides. Lat...…”

“…Recently, several families of molecular building blocks have been demonstrated to be SF-active: these include first and foremost linear acenes 12,44–52 such as tetracene and pentacene, followed by carotenoids, 53–59 diketopyrrolopyrroles, 26,32,60–67 and rylenes 31,68–76 such as perylene- and terrylene-diimides. Lately, we shifted our attention to a dimer of perylene-monoimide with napthylene as a spacer ( PMI-N-PMI ).…”

Photogeneration of Long-Lived Triplet States through Singlet Fission in Lycopene H-Aggregates

“…π-Conjugated chromophores, such as acenes − and carotenoids, − in a specific aggregate morphology are known to host SF since they satisfy the singlet–triplet energy criteria, i.e., E singlet ≥ 2 E triplet . In cases where aggregates or molecular dimers show SF to generate two spatially proximal triplets characterized by an intermediate T–T pair state, ,,− the triplet lifetimes can be as short as ∼100 ps − due to multiple recombination and relaxation pathways.…”

Efficient singlet fission in nanoparticles of amphipathic anthracene–tetracene dyad with broadband light harvesting ability

“…This is consistent with our previous observation in which the carboxyl group points outward from the nanoparticles due to the strong hydrophilic interaction between the carboxyl groups and water. 46 In other words, the carboxyl group should point outward from DPT–DPA–COOH NP. This extra hydrophilic driving force would make the DPA unit of DPT–DPA–COOH approximate to the DPA unit of adjacent DPA–COOH instead of the DPT unit in nanoparticles.…”

“…The fluorescence behavior of the DPT–DPA–COOH nanoparticles is similar with that observation in nanoparticles of some tetracene derivatives, in which the non-radiative process was assigned to SF. 46 Thus, DPT–DPA–COOH may also undergo SF in the nanoparticles. The fast decay component was caused by the occurrence of SF, and the slow decay component was attributed to the delayed fluorescence that resulted from the recombination of the geminate triplet states.…”