Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Vertical phase separation in bulk heterojunction solar cells formed by in situ polymerization of fulleride.

ABSTRACT: Vertical phase separation of the donor and the acceptor in organic bulk heterojunction solar cells is crucial to improve the exciton dissociation and charge transport efficiencies. This is because whilst the exciton diffusion length is limited, the organic film must be thick enough to absorb sufficient light. However, it is still a challenge to control the phase separation of a binary blend in a bulk heterojunction device architecture. Here we report the realization of vertical phase separation induced by in situ photo-polymerization of the acrylate-based fulleride. The power conversion efficiency of the devices with vertical phase separation increased by 20%. By optimising the device architecture, the power conversion efficiency of the single junction device reached 8.47%. We believe that in situ photo-polymerization of acrylate-based fulleride is a universal and controllable way to realise vertical phase separation in organic blends.

SUBMITTER: Zhang L

PROVIDER: S-EPMC4034005 | biostudies-other | 2014

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

Phthalocyanine blends improve bulk heterojunction solar cells.

Project description:A core phthalocyanine platform allows engineering of the solubility properties the band gap, shifting the maximum absorption toward the red. A simple method for increasing the efficiency of heterojunction solar cells uses a self-organized blend of phthalocyanine chromophores fabricated by solution processing.

| S-EPMC2836723 | biostudies-literature

Impact of Polymer Backbone Fluorination on the Charge Generation/Recombination Patterns and Vertical Phase Segregation in Bulk Heterojunction Organic Solar Cells.

Project description:Incorporating fluorine (-F) substituents along the main-chains of polymer donors and acceptors is an effective strategy toward efficient bulk-heterojunction (BHJ) solar cells. Specifically, F-substituted polymers often exhibit planar conformations, leading to favorable packing, and electronic coupling. However, the effects of fluorine substituents on the charge generation and recombination characteristics that determine the overall efficiency of BHJ active layers remain critically important issues to examine. In this report, two PBDT[2X]T polymer analogs -poly[4,8-bis((2-ethylhexyl)oxy)benzo[1,2-b:4, 5-b']dithiophene-thiophene] [PBDT[2H]T] and its F-substituted counterpart poly[4,8-bis((2-ethylhexyl)oxy)benzo[1,2-b:4,5-b']dithiophene-3,4-difluoro-thiophene] [PBDT[2F]T]-are studied to systematically examine how -F substituents impact the blend morphology, charge generation, carrier recombination and extraction in BHJ solar cells. Considering the large efficiency differences between PBDT[2H]T- and PBDT[2F]T-based BHJ devices, significant emphasis is given to characterizing the out-of-plane morphology of the blend films as vertical phase-separation characteristics are known to have dramatic effects on charge transport and carrier extraction in polymer-fullerene BHJ solar cells. Herein, we use electron energy loss spectroscopy (EELS) in tandem with charge transport characterization to examine PBDT[2X]T-fullerene blend films. Our analyses show that PBDT[2H]T and PBDT[2F]T possess very different charge generation, recombination and extraction characteristics, resulting from distinct aggregation, and phase-distribution within the BHJ blend films.

| S-EPMC7066253 | biostudies-literature

Characterising Exciton Generation in Bulk-Heterojunction Organic Solar Cells.

Project description:In this paper, characterisation of exciton generation is carried out in three bulk-heterojunction organic solar cells (BHJ OSCs)-OSC1: an inverted non-fullerene (NF) BHJ OSC; OSC2: a conventional NF BHJ OSC; and OSC3: a conventional fullerene BHJ OSC. It is found that the overlap of the regions of strong constructive interference of incident and reflected electric fields of electromagnetic waves and those of high photon absorption within the active layer depends on the active layer thickness. An optimal thickness of the active layer can thus be obtained at which this overlap is maximum. We have simulated the rates of total exciton generation and position dependent exciton generation within the active layer as a function of the thicknesses of all the layers in all three OSCs and optimised their structures. Based on our simulated results, the inverted NF BHJ OSC1 is found to have better short circuit current density which may lead to better photovoltaic performance than the other two. It is expected that the results of this paper may provide guidance in fabricating highly efficient and cost effective BHJ OSCs.

| S-EPMC7829893 | biostudies-literature

Hydrogen bonding in bulk heterojunction solar cells: a case study.

Project description:Small molecules with dithieno[3,2-b;2',3'-d]thiophene as central building block and octyl cyanoacetate and octyl cyanoacetamide as different terminal building blocks have been designed and synthesized. The amide containing small molecule can form intermolecular hydrogen bonding between N-H...O = C of the amide group. The photovoltaic properties and active layer morphologies of the two molecules in bulk heterojunction solar cells are compared to study the influence of hydrogen bonding on the active layer morphology. New methanofullerene compound containing amide group has also been synthesized and compared with conventional fullerene electron acceptors.

| S-EPMC4099981 | biostudies-literature

Substrate-oriented nanorod scaffolds in polymer-fullerene bulk heterojunction solar cells.

Project description:The use of a p-type inorganic semiconductor to form a nanorod scaffold within a polymer-fullerene bulk heterojunction solar cell is reported. The performance of this cell is compared to those made of the commonly used n-type scaffold of ZnO, which has been reported many times in the literature. The scaffold is designed to improve charge-carrier collection by increased mobility in thicker samples. Observations show that generally the device performance shows a negative correlation to nanorod length. By using CuSCN as a p-type inorganic scaffold, a very similar trend is observed.

| S-EPMC4501325 | biostudies-literature

Impact of Electrodes on Recombination in Bulk Heterojunction Organic Solar Cells.

Project description:In recent years, the efficiency of organic solar cells (OSCs) has increased to more than 13%, although different barriers are on the way for reaching higher efficiencies. One crucial barrier is the recombination of charge carriers, which can either occur as the bulk recombination of photogenerated charges or the recombination of photogenerated charges and electrodic induced charges (EICs). This work studies the impact of EICs on the recombination lifetime in OSCs. To this end, the net recombination lifetime of photogenerated charge carriers in the presence of EICs is measured by means of conventional and newly developed transient photovoltage techniques. Moreover, a new approach has been introduced to exclusively measure the bulk recombination lifetime, i.e., in the absence of EICs; this approach was conducted by depositing transparent insulating layers on both sides of the OSC active layer. An examination of these approaches on OSCs with different active layer materials, thicknesses, and varying light intensities determined that the EICs can only reduce the recombination lifetime of the photogenerated charges in OSCs with very weak recombination strength. This work supports that for OSCs with highly reduced recombination strength, eliminating the recombination of photogenerated charges and EICs is critical for achieving better performance. Therefore, the use of a proper blocking layer suppresses EIC recombination in systems with very weak recombination.

| S-EPMC5997384 | biostudies-literature

Barium: an efficient cathode layer for bulk-heterojunction solar cells.

Project description:We report Barium (Ba) cathode layer for bulk-heterojunction solar cells which enhanced the fill factor (FF) of p-DTS(FBTTh2)2/PC71BM BHJ solar cell up to 75.1%, one of the highest value reported for an organic solar cell. The external quantum efficiency exceeds 80%. Analysis of recombination mechanisms using the current-voltage (J-V) characteristics at various light intensities in the BHJ solar cell layer reveals that Ba prevents trap assisted Shockley-Read-Hall (SRH) recombination at the interface and with different thicknesses of the Ba, the recombination shifts towards bimolecular from monomolecular. Moreover, Ba increases shunt resistance and decreases the series resistance significantly. This results in an increase in the charge collection probability leading to high FF. This work identifies a new cathode interlayer which outclasses the all the reported interlayers in increasing FF leading to high power conversion efficiency and have significant implications in improving the performance of BHJ solar cells.

| S-EPMC3678135 | biostudies-other

Miscibility Tuning for Optimizing Phase Separation and Vertical Distribution toward Highly Efficient Organic Solar Cells.

Project description:Blending multidonor or multiacceptor organic materials as ternary devices has been recognized as an efficient and potential method to improve the power conversion efficiency of bulk heterojunction devices or single-junction components in tandem design. In this work, a highly crystalline molecule, DRCN5T, is involved into a PTB7-Th:PC70BM system to fabricate large-area organic solar cells (OSCs) whose blend film thickness is up to 270 nm, achieving an impressive performance of 11.1%. The significant improvement of OSCs after adding DRCN5T is due to the formation of an interconnected fibrous network with decreased ?-? stacking and enhanced domain purity, in addition to the optimized vertical distribution of PTB7-Th and PC70BM, producing more effective charge separation, transport, and collection. The optimized morphology and performance are actually determined by the miscibility in different components, which can be quantitatively described by the Flory-Huggins interaction parameter of -0.80 and 2.94 in DRCN5T:PTB7-Th and DRCN5T:PC70BM blends, respectively. The findings in this work can potentially guide the selection of an appropriate third additive for high-performance OSCs for the sake of large-area printing and roll-to-roll fabrication from the view of miscibility.

| S-EPMC6685468 | biostudies-literature

Novel Dimethylmethylene-Bridged Triphenylamine-PDI Acceptor for Bulk-Heterojunction Organic Solar Cells.

Project description:A novel, star-shaped electron acceptor, DMTPA-PDI3, derived from a planar dimethylmethylene-bridged triphenylamine core with three acetylene-linked perylene diimide (PDI) units is developed as a nonfullerene acceptor for organic solar cells (OSCs). DMTPA-PDI3 manifests significantly reduced intramolecular twisting, enabling sufficient system-wide π-electron delocalization leading to broadened spectral absorption and raised lowest unoccupied molecular orbital level. As a result, higher and more balanced hole and electron transport properties are observed. Active layers for OSCs comprising DMTPA-PDI3 acceptor and PBT7-Th donor exhibit suppressed intermolecular aggregation, giving rise to uniform nanophase network formation. These OSC devices have afforded respectably high power-conversion efficiency of about 5%.

| S-EPMC5644237 | biostudies-literature

Columnar-Structured Low-Concentration Donor Molecules in Bulk Heterojunction Organic Solar Cells.

Project description:We investigate the arrangement of donor molecules in vacuum-deposited bulk heterojunction (BHJ) 1,1-bis-(4-bis(4-methyl-phenyl)-amino-phenyl)-cyclohexane (TAPC):C70-based organic solar cells (OSCs). Even a low dose of donors (∼10%) forms columnar structures that provide pathways for efficient hole transport in the BHJ layer; however, these structures disappear at donor concentrations below 10%, generating disconnected and isolated hole pathways. The formation of columnar donor structures is confirmed by the contrast of the contact potential difference, measured by Kelvin probe force microscopy, and by the trap-assisted charge injection at low donor concentrations. The mobility of electrons and holes is well balanced in OSCs owing to the preservation of the hole mobility at such low donor concentrations, consequently maximizing the internal quantum efficiency of the OSCs. A high power conversion efficiency of 6.24% was achieved in inverted TAPC:C70 (1:9) OSCs.

| S-EPMC6641345 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data