Near infrared light driven organic p-i-n solar cells incorporating phthalocyanine J-aggregate

Hiramoto, Masahiro; Kitada, Keitaro; Iketaki, Kai; Kaji, Tatsuru

doi:10.1063/1.3534804

Cited by 53 publications

(51 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This will increase the response from both D and A even when a small amount of D is present. 38 However, the response of our PM-HJ device in the vis region is decreased compared with the reference device. This means that the dissociation efficiency of C 70 excitons is reduced, which is contrary to our expectation.…”

Section: Resultsmentioning

confidence: 95%

High-Performance Organic Small-Molecule Panchromatic Photodetectors

Hou

Wang

et al. 2015

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

High-performance panchromatic organic photodetectors (OPDs) containing small molecules lead phthalocyanine (PbPc) and C70 fullerene as donor and acceptor, respectively, were demonstrated. The OPDs had either a PbPc/C70 planar heterojunction (PHJ) or a PbPc/PbPc:C70/C70 hybrid planar-mixed molecular heterojunction (PM-HJ) structure. Both the PHJ and the PM-HJ devices showed a broad-band response that covered wavelengths from 300 to 1100 nm. An external quantum efficiency (EQE) higher than 10% and detectivity on the order of 10(12) Jones were obtained in the wavelength region from 400 to 900 nm for the PHJ device. The EQE in the near-infrared region was enhanced by using the PM-HJ device structure, and a maximum EQE of 30.2% at 890 nm was observed for the optimized device with a 5% PbPc-doped C70 layer. Such an EQE is the highest at this wavelength of reported OPDs. The detectivity of the PM-HJ devices was also higher than that of the PHJ one, which is attributed to the increased efficiency of exciton dissociation in bulk heterojunction structure, increased absorption efficiency caused by formation of triclinic PbPc in the PbPc:C70 mixed film when it was deposited on a pristine PbPc layer, and high hole mobility of the PbPc-doped C70 layer.

show abstract

Section: Resultsmentioning

confidence: 95%

High-Performance Organic Small-Molecule Panchromatic Photodetectors

Hou

Wang

et al. 2015

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

show abstract

“…[4][5] The chlorosomal Jaggregates not only exhibit high exciton mobility superior to any other organic molecular systems 6 but also are synthesizable and chemically modifiable in vitro. 7 Therefore, chlorosomes are envisioned as a potential building block of nanoscale optoelectronic devices such as solar cells, [8][9] photodetectors, 10 and other excitonic devices. [11][12] In chlorosomes, a series of EET processes occur on a broad range of time scales from tens of femtoseconds (fs) to hundreds of picoseconds (ps), while the interpretation of individual EET steps is still controversial due to (1) variation of their time scales depending on the probing technique or the type of BChls constituting chlorosomes and (2) complex hierarchical structure of chlorosomes consisting of multi-layered tubes and/or curved lamellar layers with significant structural disorder.…”

Section: Introductionmentioning

confidence: 99%

Role of thermal excitation in ultrafast energy transfer in chlorosomes revealed by two-dimensional electronic spectroscopy

Jun

Yang

Kim

et al. 2015

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

Chlorosomes are the largest light harvesting complexes in nature and consist of many bacteriochlorophyll pigments forming self-assembled J-aggregates. In this work, we use two-dimensional electronic spectroscopy (2D-ES) to investigate ultrafast dynamics of excitation energy transfer (EET) in chlorosomes and their temperature dependence. From time evolution of the measured 2D electronic spectra of chlorosomes, we directly map out the distribution of the EET rate among the manifold of exciton states in a 2D energy space. In particular, it is found that the EET rate varies gradually depending on the energies of energy-donor and energy-acceptor states. In addition, from comparative 2D-ES measurements at 77 K and room temperature, we show that the EET rate exhibits subtle dependence on both the exciton energy and temperature, demonstrating the effect of thermal excitation on the EET rate. This observation suggests that active thermal excitation at room temperature prevents the excitation trapping at low-energy states and thus promotes efficient exciton diffusion in chlorosomes at ambient temperature.

show abstract

“…This kind of low-energy absorption can also be utilized for materials such as organic solar cells made from the J-aggregate of lead phthalocyanine. 6 The π-stacked arrays of open-shell molecules are known to exhibit further lower energy absorption with large absorbance. One-dimensional (1D) columns of ion-radical species of tetracyanoquinodimethane and tetrathiafulvalene derivatives exhibit NIR absorption bands at 1000-2000 nm.…”

mentioning

confidence: 99%

Near-infrared absorption of π-stacking columns composed of trioxotriangulene neutral radicals

et al. 2017

View full text Add to dashboard Cite

A long-wavelength photoabsorption of organic molecules has been noticed because of the potential as materials. In addition to the extension of π conjugation, molecular aggregation has been utilized to realize the elongation of absorption wavelength. We report strong near-infrared absorptions of trioxotriangulene neutral radicals in the crystalline state and large-scale theoretical calculations of the radical assemblies interpreting the mechanism of optical properties. Polarized absorption spectra and X-ray diffraction of the crystals clarified that an unusual π-stacking column consisting of π-dimers is key for this absorption. Quantum chemical calculations based on time-dependent density functional theory revealed that the π-dimer shows an electronic transition between frontier orbitals generated by strong coupling of the delocalized singly occupied orbitals of monomers. The interdimer interaction of transition dipole moments, which are parallel to the column, elucidated the increase of absorption wavelength. The divide-andconquer Green function method enabled the large-scale time-dependent density functional theory calculation up to a 60mer, where the maximum number of atoms is 4380, reproducing the near-infrared absorptions of trioxotriangulene crystals. The present method to investigate the mechanism of the long-wavelength photoabsorption is useful for developing organic materials consisting of stable neutral radicals.

show abstract

Near infrared light driven organic p-i-n solar cells incorporating phthalocyanine J-aggregate

Cited by 53 publications

References 14 publications

High-Performance Organic Small-Molecule Panchromatic Photodetectors

High-Performance Organic Small-Molecule Panchromatic Photodetectors

Role of thermal excitation in ultrafast energy transfer in chlorosomes revealed by two-dimensional electronic spectroscopy

Near-infrared absorption of π-stacking columns composed of trioxotriangulene neutral radicals

Contact Info

Product

Resources

About