Perylenediimides as more than just non-fullerene acceptors: versatile components in organic, hybrid and perovskite solar cells

The most recent advances in the incorporation of perylenediimides in photovoltaic devices are highlighted.

Achieving Optimal Bulk Heterojunction in All-Polymer Solar Cells by Sequential Processing with Nonorthogonal Solvents

Developing efficient all-polymer solar cells (all-PSCs) has always been a long-standing challenge due to the unfavorable morphology caused by conventional blend casting (BC). Here, we first employ the methodology of sequential processing (SP) with nonorthogonal solvents to fabricate facilely all-PSCs. A highly crystalline polymer donor, PBDB-T, is used to construct a well-organized underlying film, while a new polymer, FPDI-BT1, is selected as the acceptor to be intercalated into the amorphous or semicrystalline regions of PBDB-T during the secondary deposition. By tuning the solvent composition for FPDI-BT1 processing, a bulk heterojunction-like configuration, rather than a traditional bilayer device, is obtained facilely without the need of further processing treatment. The extremely boosted power conversion efficiency of 7.15% from the SP device is achieved, which is more than twice as efficient as the BC analogue (3.57%). The results demonstrate that SP is a promising strategy to fabricate high-performance all-PSCs with tunable configurations of active layers.

Diels–Alder reaction on perylenediimides: synthesis and theoretical study of core-expanded diimides

(Un)substituted perylenediimides react with (un)functionalized benzynes yielding core-expanded diimides.

Fluoride-mediated alkoxylation and alkylthio-functionalization of halogenated perylenediimides

The presence of fluoride ions in the reaction of chloro- or bromo-PDIs with alcohols and thiols leads to a spectacular increase in the yields of substituted compounds.

Exfoliation and supramolecular functionalization of graphene with an electron donor perylenediimide derivative

Exfoliation of graphene with 1-N-methylpiperazine-perylenediimide (Pip-PDI) and supramolecular formation of Pip-PDI/graphene ensembles.

Direct alkylthio-functionalization of unsubstituted perylenediimides

A simple fluoride-mediated reaction allows the synthesis of 1,6-dialkylthioperylenediimides from unsubstituted perylenediimides under very mild conditions.

Effect of Molecular Stacking on Exciton Diffusion in Crystalline Organic Semiconductors

Exciton diffusion is at the heart of most organic optoelectronic devices' operation, and it is currently the most limiting factor to their achieving high efficiency. It is deeply related to molecular organization, as it depends on intermolecular distances and orbital overlap. However, there is no clear guideline for how to improve exciton diffusion with regard to molecular design and structure. Here, we use single-crystal charge-transfer interfaces to probe favorable exciton diffusion. Photoresponse measurements on interfaces between perylenediimides and rubrene show a higher photocurrent yield (+50%) and extended spectral coverage (+100 nm) when there is increased dimensionality of the percolation network and stronger orbital overlap. This is achieved by very short interstack distances in different directional axes, which favors exciton diffusion by a Dexter mechanism. Even if the core of the molecule shows strong deviation from planarity, the similar electrical resistance of the different systems, planar and nonplanar, shows that electronic transport is not compromised. These results highlight the impact of molecular organization in device performance and the necessity of optimizing it to take full advantage of the materials' properties.

Does a nitrogen matter? Synthesis and photoinduced electron transfer of perylenediimide donors covalently linked to C59N and C60 acceptors

The first perylenediimide (PDI) covalently linked to an azafullerene (C59N) is described. PDI-C59N and PDI-C60 dyads where PDI acts as an electron-donor moiety have been synthesized by connection of the balls to the PDI 1-bay position. Photoexcitation of the PDI unit in both systems results in formation of the charge-separated state by photoinduced electron transfer from the singlet excited state of the PDI moiety to the C59N or to the C60 moiety. The charge-separated state has a lifetime of 400 ps in the case of PDI-C59N and 120 ps for the PDI-C60 dyad in benzonitrile at 298 K. This result has significant implications for the design of organic solar cells based on covalent donor-acceptor systems using C59N as an electron acceptor, indicating that longer-lived charge-separated states can be attained using C59N systems instead of C60 systems.

Submillisecond-lived photoinduced charge separation in a fully conjugated phthalocyanine–perylenebenzimidazole dyad

A fully electronically conjugated phthalocyanine–perylenemonoimidebenzimidazole system has been synthesized, in which the conjugation goes through the imide position of the perylene.

High charge carrier mobility and efficient charge separation in highly soluble perylenetetracarboxyl-diimides

In this communication we report on the synthesis and charge mobility of highly soluble perylenebisimid derivatives.