Aggregation-Induced Increase of the Quantum Yield of Electron Injection from Chalcogenorhodamine Dyes to TiO<sub>2</sub>

Mulhern, Kacie R.; Detty, Michael R.; Watson, David F.

doi:10.1021/jp111438x

Cited by 63 publications

(116 citation statements)

References 87 publications

Supporting

Mentioning

110

Contrasting

Order By: Relevance

“…It is noteworthy that these values are significantly lower than those obtained in the solution electrochemistry and the differences of HOMO levels between TT and TS are negligible in contrast to the DFT calculated results [55]. This can be understood by conjugation enhancement within the molecules and the orientation of molecules from the aggregation-induced close packing and the HOMO levels' location (mainly on aromatic parts of the molecules as indicated by the DFT calculation) [14,17,56]. The LUMO levels of the dyes are derived from the difference between the absorption edge (the band gap) of the dyes on TiO 2 and the HOMO levels from solid-state voltammetry.…”

Section: Resultsmentioning

confidence: 54%

“…When the organic dye covers TiO 2 surface, the aggregation of some dyes occurs sometimes, which has been suggested to be harmful to the energy conversion efficiency of the solar cells [10,13]. In contrast, there are some papers that report that the aggregation of the dyes on TiO 2 benefits the energy conversion efficiency [14][15][16][17][18][19][20]. Such a contradiction reveals that the band structures, as well as the redox properties, of the dye molecules, especially in the solid-state solar cells where the charge transfer occurs between the dye and TiO 2 ( or the hole transporting materials), should be considered in the solid state.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Determination of HOMO levels of organic dyes in solid-state electrochemistry

Yang

Tang

Feng

et al. 2014

J Solid State Electrochem

View full text Add to dashboard Cite

The solid-state electrochemistry of organic dyes, TT(2-cyano-3-(4-hexyl-5-dimethyltriphenylamine-thien-2-y l ) a c r y l i c a c i d ) , T T N a ( 2 -c y a n o -3 -( 4 -h e x y l -5 -dimethyltriphenylamine-thien-2-yl)acrylic acid sodium salt), and TS(2-[5-(4-hexyl-5-dimethyltriphenylamine-thien-2-yl)methylene-4-oxo-2-thioxothiazolidin-3-yl]acetic acid), was investigated. The redox processes of the solid dyes are electrochemically quasi-reversible. The electrochemical oxidation behaviors of these dye are similar because of the identical donor moieties and the highest occupied molecular orbital (HOMO) distribution in the dyes as revealed by density functional theory (DFT) calculation. The AC impedance spectra show that the dye film shows negative differential resistance characteristics in the high-frequency range and finite diffusion responses in the low-frequency range at higher potentials, which indicates the nonlinear charge transport and limited diffusion of counterions in the solid-state film. The onset oxidation potential of the solid dyes in the cyclic voltammetry does not affected by the ion diffusion. The cyclic voltammetry can be employed to derive reliable HOMO and lowest unoccupied molecular orbital (LUMO) levels of the solid dyes.

show abstract

Section: Resultsmentioning

confidence: 54%

Section: Introductionmentioning

confidence: 99%

Determination of HOMO levels of organic dyes in solid-state electrochemistry

Yang

Tang

Feng

et al. 2014

J Solid State Electrochem

View full text Add to dashboard Cite

show abstract

“…Firstly, a difference in oxidation potentials of excited/ground state monomer and aggregated species may lead to a difference in driving force for electron injection due to the higher energy excited states of H-aggregates. 40,17 Alternatively, this difference could influence the strength of the electronic coupling between the excited monomer/aggregate and TiO2 acceptor states. 17 A hole-trapping mechanism is an alternative explanation for differing photocurrent yields from monomer and dimer/aggregate species.…”

Section: Discussionmentioning

confidence: 99%

“…40,17 Alternatively, this difference could influence the strength of the electronic coupling between the excited monomer/aggregate and TiO2 acceptor states. 17 A hole-trapping mechanism is an alternative explanation for differing photocurrent yields from monomer and dimer/aggregate species. Initially proposed in the context of the photographic process, 37 the hole-trapping mechanism considers that dye aggregates can contain trap states for excitons.…”

Section: Discussionmentioning

confidence: 99%

“…13,14 Cyanine dyes are prone to aggregation, forming a range of molecular species in both solution, 15 and when adsorbed on a photoelectrode surface. [16][17][18] Such aggregates form with different geometric arrangements of dye monomers leading to distinct blue or red shifts and are labelled as H-or J-aggregates, 19 where H aggregates have blue shifted and J aggregates have red shifted absorbance relative to the dye monomer.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Probing the Relative Photoinjection Yields of Monomer and Aggregated Dyes into ZnO Crystals

King

Parkinson

2017

Langmuir

View full text Add to dashboard Cite

Cyanine dyes, often used in dye-sensitized solar cells (DSSCs), form a range of molecular species from monomers to large H and J aggregates in both solution and when adsorbed at a photoelectrode surface. To determine the relative capability of the different dye species to inject photoexcited electrons into a wideband gap oxide semiconductor, sensitization at a single-crystal zinc oxide surface was studied by simultaneous attenuated reflection (ATR) ultraviolet-visible (UV-vis) absorption and photocurrent spectroscopy measurements. ATR measurements enable identification of the dye species populating the surface with simultaneous photocurrent spectroscopy to identify the contribution of the various dye forms to photocurrent signal. We study the dye 2,2'-carboxymethylthiodicarbocyanine bromide that is particularly prone to aggregation both in solution and at the surface of sensitized oxide semiconductors.

show abstract

Selenium and Tellurium Heterocycles

Logan

Lang

Detty

2014

Patai's Chemistry of Functional Groups

View full text Add to dashboard Cite

Synthetic pathways leading to tellurium‐ and selenium‐containing heterocycles are summarized for the period 1995 to the present. In addition, the utility of various tellurium‐ and selenium‐containing heterocycles are summarized. Primarily, the synthesis of tellurium‐ and selenium‐containing heterocycles of five‐ and six‐membered rings are described with various degrees of unsaturation, as well as their benzo‐fused analogues. In particular, the syntheses of selenophenes , tellurophenes and their mono‐ and dibenzo‐fused analogues are described. Similarly, syntheses of tellurazoles, selenazoles, telluradiazoles, selenadiazoles and their benzo‐fused analogues are described. Among the six‐membered rings, synthetic routes to telluropyrans and selenopyrans and their benzo analogues are described. Further degrees of unsaturation provide the telluropyrylium and selenopyrylium compounds and their benzo‐ and dibenzo‐fused analogues. Synthetic routes to chalcogenopyrylium compounds, chalcogenorosamine compounds and chalcogenorhodamine compounds are described and some of the uses of these materials are also provided. A review of synthetic routes to the core‐modified porphyrins—21‐chalcogenoporphyrins and 21,23‐dichalcogenoporphyrins—is also provided. Porphyrin‐like molecules with an expanded structure of five or six‐membered rings in the porphyrin core are also reviewed.

show abstract

Aggregation-Induced Increase of the Quantum Yield of Electron Injection from Chalcogenorhodamine Dyes to TiO₂

Cited by 63 publications

References 87 publications

Determination of HOMO levels of organic dyes in solid-state electrochemistry

Determination of HOMO levels of organic dyes in solid-state electrochemistry

Probing the Relative Photoinjection Yields of Monomer and Aggregated Dyes into ZnO Crystals

Selenium and Tellurium Heterocycles

Contact Info

Product

Resources

About

Aggregation-Induced Increase of the Quantum Yield of Electron Injection from Chalcogenorhodamine Dyes to TiO2

Cited by 63 publications

References 87 publications

Determination of HOMO levels of organic dyes in solid-state electrochemistry

Determination of HOMO levels of organic dyes in solid-state electrochemistry

Probing the Relative Photoinjection Yields of Monomer and Aggregated Dyes into ZnO Crystals

Selenium and Tellurium Heterocycles

Contact Info

Product

Resources

About

Aggregation-Induced Increase of the Quantum Yield of Electron Injection from Chalcogenorhodamine Dyes to TiO₂