Semitransparent Organic Solar Cells with Homogeneous Transmission and Colorful Reflection Enabled by an ITO‐Free Microcavity Architecture

Abstract

Semitransparent organic photovoltaics (ST‐OPVs), owing to the merits of high power generation, thermal insulation and aesthetic features, have become a promising candidate for intellectual building‐ integrated photovoltaic windows. However, the traditional optical evaluation only focuses on the transmission properties and ignores the reflection behaviors. And the lack of quantitative descriptions for array appearance hinders implementation of ST‐OPV based large‐area modules. To tackle with these issues, we introduce an ITO‐free optical microcavity architecture into ST‐OPVs for achieving high homogeneity in transmittance with controllable reflective appearances through tunning the thickness of individual component layers. We further propose a set of parameters based on optical characteristics of sub‐ units to provide a quantitative description for the transmittance brightness, transmissive and reflective color purity, and versatility of optical arrays. The optical simulations reveal that reflection modulation from blue to red colors could be realized for devices based on various bulk‐heterojunction material systems through regulating the thickness of active layers and anti‐ reflection coatings. This work offers a viable design strategy for ST‐OPVs toward applications in next‐generation smart photovoltaic windows.This article is protected by copyright. All rights reserved