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A scalable, two-step synthesis facilitates the preparation of a polymer library of varying side chain and co-monomer, enabling rapid photovoltaic device screening. FO6-T emerged as the optimal donor achieving 15.4% PCE with L8BO as the acceptor.

A scalable, two-step synthesis facilitates the preparation of a polymer library of varying side chain and co-monomer, enabling rapid photovoltaic device screening. FO6-T emerged as the optimal donor achieving 15.4% PCE with L8BO as the acceptor.

Light-induced formation of fullerene/BCP CT complexes results in new electronic states which enable efficient electron-transport through BCP to the electrode.

Light-induced formation of fullerene/BCP CT complexes results in new electronic states which enable efficient electron-transport through BCP to the electrode.

Emergent bioelectronic technologies are underpinned by the organic electrochemical transistor (OECT), which employs an electrolyte medium to modulate the conductivity of its organic semiconductor channel. Here we utilize postpolymerization modification (PPM) on a conjugated polymer backbone to directly introduce glycolated or anionic side chains via fluoride displacement. The resulting polymers demonstrated increased volumetric capacitances, with subdued swelling, compared to their parent polymer in p-type enhancement mode OECTs. This increase in capacitance was attributed to their modified side chain configurations enabling cationic charge compensation for thin film electrochemical oxidation, as deduced from electrochemical quartz crystal microbalance measurements. An overall improvement in OECT performance was recorded for the hybrid glycol/ionic polymer compared to the parent, owing to its low swelling and bimodal crystalline orientation as imaged by grazing-incidence wide-angle X-ray scattering, enabling its high charge mobility at 1.02 cm2·V-1·s-1. Compromised device performance was recorded for the fully glycolated derivative compared to the parent, which was linked to its limited face-on stacking, which hindered OECT charge mobility at 0.26 cm2·V-1·s-1, despite its high capacitance. These results highlight the effectiveness of anionic side chain attachment by PPM as a means of increasing the volumetric capacitance of p-type conjugated polymers for OECTs, while retaining solid-state macromolecular properties that facilitate hole transport.