Cost-Effective Poly(3-Alkylthiophene)-Based Organic Photovoltaics: Advancing Solar Energy Conversion and Photodetection Technologies

Abstract

Poly(3-alkylthiophene)s (P3ATs), particularly poly(3-hexylthiophene) (P3HT), have emerged as cornerstone materials for cost-effective organic photovoltaics, bridging efficiency, scalability, and solution processability. This review systematically outlines advancements in P3AT-based organic solar cells (OSCs) and photodetectors (OPDs), focusing on synthesis, structure-property relationships, and application-driven optimization. Innovations in polymerization techniques, such as Grignard metathesis and direct arylation polycondensation, enable high regioregularity and eco-friendly production. Critical structural parameters—molecular weight, regioregularity, and side-chain engineering—are dissected, with medium molecular weight and tailored alkyl chains optimizing charge transport and morphology. Ternary blending, solvent engineering, and post-processing strategies further enhance device performance, achieving high power conversion efficiency for OSCs and specific detectivities exceeding 1014 Jones for OPDs. Photomultiplication mechanisms and spectral engineering enable ultrahigh responsivity (EQE >770000%) and narrowband detection. Application-oriented designs, including stretchable all-polymer systems and semi-transparent architectures, highlight P3ATs’ versatility in wearable electronics and building-integrated photovoltaics. Future directions emphasize green solvents, simplified nonfullerene acceptors, and machine learning-guided material design to advance commercialization. By synergizing material innovation with scalable processing, P3ATs offer a sustainable pathway for next-generation organic optoelectronics, balancing performance, stability, and environmental impact.