Elucidating Charge Generation in Green-Solvent Processed Organic Solar Cells.

Safa Shoaee,Giuseppe Sforazzini,Anna Laura Sanna

doi:10.3390/molecules26247439

Abstract

Organic solar cells have the potential to become the cheapest form of electricity. Rapid increase in the power conversion efficiency of organic solar cells (OSCs) has been achieved with the development of non-fullerene small-molecule acceptors. Next generation photovoltaics based upon environmentally benign “green solvent” processing of organic semiconductors promise a step-change in the adaptability and versatility of solar technologies and promote sustainable development. However, high-performing OSCs are still processed by halogenated (non-environmentally friendly) solvents, so hindering their large-scale manufacture. In this perspective, we discuss the recent progress in developing highly efficient OSCs processed from eco-compatible solvents, and highlight research challenges that should be addressed for the future development of high power conversion efficiencies devices.

Highlights

Introduction to organic solar cells (OSCs)Organic solar cells with a bulk heterojunction architecture consist of an active layer phase-segregated domains of the electron donor and the acceptor components [21].Such BHJ solar cells are commonly prepared by combining conjugated donor (D) polymers with electron-accepting (A) molecules
This is due to either solubility limitations and/or other morphological aspects, such as interactions of the solvents and components, as well as the rate of solvent evaporation. These have been addressed extensively in recent reviews [19]. In this perspective we focus on the implication of the morphology on charge generation
The proceeding sections showcased the constant development of novel materials rapidly pushing forward the Power conversion efficiencies (PCE) of OSCs

Summary

Introduction to OSCs

Organic solar cells with a bulk heterojunction architecture consist of an active layer phase-segregated domains of the electron donor and the acceptor components [21]. Such BHJ solar cells are commonly prepared by combining conjugated donor (D) polymers with electron-accepting (A) molecules. This leads to an interpenetrating network with a large D-A contact area, where the absorbing site is within a few nanometers of the donorwhere e is the charge of an electron, εr is the dielectric constant of the surrounding acceptor interface.

Morphology of the photoactive layer

Morphology of the Photoactive Layer

Design towards

Photoluminescence Assay of Exciton Dissociation

Findings

Concluding Remarks