Suppressing Recombination in Polymer Photovoltaic Devices via Energy‐Level Cascades

Tan, Zhi‐Kuang; Johnson, Kerr; Vaynzof, Yana; Bakulin, Artem A.; Chua, Lay‐Lay; Ho, Peter K. H.; Friend, Richard H.

doi:10.1002/adma.201300243

Cited by 58 publications

(70 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In all cases, PCE was improved compared to the equivalent donor-acceptor bilayer. It was additionally shown that increasing cascade layer thickness beyond 3nm had little impact [405], or indeed reduced the benefit on performance [404], again in agreement with KMC simulations [402].…”

Section: 2supporting

confidence: 77%

“…KMC simulations suggest a thin (<3nm) 'cascade' layer between donor and acceptor, and  = 150meV is sufficient to reduce GR from over 90% to levels reported in P3HT:PC61BM OPVs [402]. Izawa et al [403], Heidel et al [404], and Tan et al [405] all report experiments in which a thin layer (<2nm) of 'cascade' material with  = 120meV, 300meV and 400meV respectively was interposed between the donor and acceptor. In all cases, PCE was improved compared to the equivalent donor-acceptor bilayer.…”

Section: 2mentioning

confidence: 99%

See 1 more Smart Citation

Simulating charge transport in organic semiconductors and devices: a review

Groves

2016

Rep. Prog. Phys.

View full text Add to dashboard Cite

The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. AbstractCharge transport simulation can be a valuable tool to better understand, optimise and design organic transistors (OTFTs), organic photovoltaics (OPVs), and light-emitting diodes (OLEDs). This review presents an overview of common charge transport and device models; namely drift-diffusion, master equation, mesoscale kinetic Monte Carlo and quantum chemical Monte Carlo, and a discussion of the relative merits of each. This is followed by a review of the application of these models as applied to charge transport in organic semiconductors and devices, highlighting in particular the insights made possible by modelling. The review concludes with an outlook for charge transport modelling in organic electronics.

show abstract

Section: 2supporting

confidence: 77%

Section: 2mentioning

confidence: 99%

Simulating charge transport in organic semiconductors and devices: a review

Groves

2016

Rep. Prog. Phys.

View full text Add to dashboard Cite

show abstract

“…The cascade is in this case an intrinsic property, rather than the result of a tailored interlayer comprising a third molecular species [39,194]. The homogeneity of the mesoscale fields also implies an important functional difference between an electrostatic and a purely chemical level offset, pointed to in Fig.…”

Section: The Role Of Interfacial Defectsmentioning

confidence: 93%

The (Non-)Local Density of States of Electronic Excitations in Organic Semiconductors

Poelking

2018

Springer Theses

View full text Add to dashboard Cite

The (Non-)Local Density of States of Electronic Excitations in Organic Semiconductors The rational design of organic semiconductors for optoelectronic devices relies on a detailed understanding of how their molecular and morphological structure condition the energetics and dynamics of charged and excitonic states. Investigating the role of molecular architecture, conformation, orientation and packing, this work reveals mechanisms that shape the spatially resolved densities of states in organic, small-molecular and polymeric heterostructures and mesophases. The underlying computational framework combines multiscale simulations of the material morphology at atomistic and coarse-grained resolution with a long-range-polarized embedding technique to resolve the electronic structure of the molecular solid. We show that longrange electrostatic interactions tie the energetics of microscopic states to the mesoscopic structure, with a qualitative and quantitative impact on charge-carrier level profiles across organic interfaces. The computational approach provides quantitative access to the charge-density-dependent opencircuit voltage of planar heterojunctions. The derived and experimentally verified relationships between molecular orientation, architecture, level profiles and open-circuit voltage rationalize the acceptor-donor-acceptor pattern for donor materials in high-performing solar cells. Proposing a pathway for barrier-less dissociation of charge transfer states, we highlight how mesoscale fields generate charge splitting and detrapping forces in systems with finite interface roughness. The associated design rules reflect the dominant role played by lowest-energy configurations at the interface. Acknowledgements 121 Die (nicht-)lokale Zustandsdichte elektronischer Anregungen in organischen Halbleitern List of Publications 123Bibliography 125 Chapter 1 Organic Electronics in a NutshellThe discovery of conductive polymers in the 1970s [1,2] -rewarded with the Nobel prize in chemistry in the year 2000 -and subsequent development of the first polymeric electronic devices in the 1980s [3-5] have marked the beginnings of a vast interdisciplinary research field referred to as organic electronics. Drawing from both polymeric and small-molecular semiconductors, organic thin-film transistors, solar cells, light-emitting diodes, photodetectors and sensors name just a few out of many applications that make use of the supreme chemical versatility and mechanical flexibility of the underlying "soft" molecular materials. Furthermore enabling low-temperature solution-based processing, printing and spray coating, organic electronics is set to complement the conventional silicon-based electronics in diverse waysadding functionality and improving sustainability. This introductory chapter will provide a short review of the materials and device physics, as well as of new trends and challenges that emerged in the field over the past decade. MaterialsOrganic semiconductors are molecular materials that exist at the interface between orga...

show abstract

“…[27] With this method, a PHJ solar cell with three polymer layers on top of each other was realized. [28] The materials featured cascaded energy levels achieving an efficiency of 0.45%. In addition, P3HT was also crosslinked by the use of sFPA.…”

Section: Overview Of the Chemistry Of Crosslinkable Materialsmentioning

confidence: 99%

“…More specifically, crosslinked layers may be used as exciton blocking or transport layers at the electrodes allowing for subsequent deposition of further layers from solution or preventing materials from diffusing into each other. [27,28,44] However, to date, to best of our knowledge there is no report about advanced multilayer organic solar cell devices that are fully processed from solution using several crosslinked layers. Wellknown examples such as the work by Janssen and co-workers [13a] or Leo and co-workers [45] still rely on solution-processed inorganic interlayers or vacuum-deposited small molecules.…”

Section: Application Of Crosslinking In Organic Photovoltaicsmentioning

confidence: 99%

Crosslinked Semiconductor Polymers for Photovoltaic Applications

Kahle

Saller

Köhler

et al. 2017

Advanced Energy Materials

View full text Add to dashboard Cite

Organic solar cells (OSCs) have achieved much attention and meanwhile reach efficiencies above 10%. One problem yet to be solved is the lack of long term stability. Crosslinking is presented as a tool to increase the stability of OSCs. A number of materials used for the crosslinking of bulk heterojunction cells are presented. These include the crosslinking of low bandgap polymers used as donors in bulk heterojunction cells, as well as the crosslinking of fullerene acceptors and crosslinking between donor and acceptor. External crosslinkers often based on multifunctional azides are also discussed. In the second part, some work either leading to OSCs with high efficiencies or giving insight into the chemistry and physics of crosslinking are highlighted. The diffusion of low molar mass fullerenes in a crosslinked matrix of a conjugated polymer and the influence of crosslinking on the carrier mobility is discussed. Finally, the use of crosslinking to make stable interlayers and the solution processing of multilayer OSCs are discussed in addition to presentation of a novel approach to stabilize nanoimprinted patterns for OSCs by crosslinking.

show abstract

Suppressing Recombination in Polymer Photovoltaic Devices via Energy‐Level Cascades

Cited by 58 publications

References 41 publications

Simulating charge transport in organic semiconductors and devices: a review

Simulating charge transport in organic semiconductors and devices: a review

The (Non-)Local Density of States of Electronic Excitations in Organic Semiconductors

Crosslinked Semiconductor Polymers for Photovoltaic Applications

Contact Info

Product

Resources

About