High-fidelity self-assembly pathways for hydrogen-bonding molecular semiconductors

Abstract

The design of molecular systems with high-fidelity self-assembly pathways that include several levels of hierarchy is of primary importance for the understanding of structure-function relationships, as well as for controlling the functionality of organic materials. Reported herein is a high-fidelity self-assembly system that comprises two hydrogen-bonding molecular semiconductors with regioisomerically attached short alkyl chains. Despite the availability of both discrete cyclic and polymeric linear hydrogen-bonding motifs, the two regioisomers select one of the two motifs in homogeneous solution as well as at the 2D-confined liquid-solid interface. This selectivity arises from the high directionality of the involved hydrogen-bonding interactions, which renders rerouting to other self-assembly pathways difficult. In thin films and in the bulk, the resulting hydrogen-bonded assemblies further organize into the expected columnar and lamellar higher-order architectures via solution processing. The contrasting organized structures of these regioisomers are reflected in their notably different miscibility with soluble fullerene derivatives in the solid state. Thus, electron donor-acceptor blend films deliver a distinctly different photovoltaic performance, despite their virtually identical intrinsic optoelectronic properties. Currently, we attribute this high-fidelity control via self-assembly pathways to the molecular design of these supramolecular semiconductors, which lacks structure-determining long aliphatic chains.

Towards the Prediction of Global Solution State Properties for Hydrogen Bonded, Self‐Associating Amphiphiles

“…Ac orrelation is alsoo bserved between CMC and compound counter cation (1,(8)(9)(10)(11). Here, theoreticalv alues of relative polarizability for those counter cations contained within the structures of 1, 8-11 werec alculated.…”

“…Within this series of compounds( 1-31), we have also included variations in counter cation (7)(8)(9)(10)(11)(12)(13). The presence of competitive ion-ion pair effects is well known to be problematic when observing hydrogen bond complexation events.…”

“…Specific examples include those from Ikkala and co‐workers who have used this class of non‐covalent complex formation to drive the self‐assembly of cobalt nanostructures for capsid production;7 Yagai and co‐workers who have used hydrogen bond formation within the construction of novel molecular semi‐conductors;8 Steed and co‐workers who have shown that hydrogen bonds can act as a substitute for covalent bonds in the production of novel supramolecular gels;9 and Zhou and co‐workers who have used hydrogen bonded amphiphile self‐association processes to drive the construction of novel drug/gene delivery systems 10…”

“…[6] Within the extensive area of non-covalents elf-associated materiald esign, there is ag rowing interest in the focusedu se of intermolecular hydrogen bonds. Specific examples include those from Ikkala and co-workers who have used this class of non-covalent complex formation to drive the self-assembly of cobaltn anostructures for capsid production; [7] Yagai and coworkers who have used hydrogen bond formationw ithin the construction of novel molecular semi-conductors; [8] Steed and co-workersw ho have shown that hydrogen bonds can act as a substitute for covalent bonds in the production of novel supramolecular gels; [9] and Zhou and co-workers who have used hydrogen bonded amphiphile self-associationp rocesses to drive the construction of novel drug/gene delivery systems. [10] The use of low molecular weight( < 500), neutral, hydrogen bond donator (HBD) receptors for the selective coordination of anion guest species is well known.…”

Self‐Aggregation of Oligomethylene‐Tethered Diketopyrrolopyrrole Dimers

“…Aggregation of dye molecules also crucially affect the performance of organic devices such as bulk heterojunction organic photovoltaics (BHJ‐OPV) wherein nanoscopic phase‐separation of different organic materials in their blends is a key to determine device performance . In this context, control over dye aggregation via supramolecular design with specific noncovalent interactions such as hydrogen‐bonding is promissing, but this approach sometimes leads to dramatically different aggregated structure depending on the conditions and small structural difference as a result of pathway complexity …”