Optical management in organic photovoltaic devices

Abstract

Due to their potentials in light-weight, flexible, and semitransparent devices, organic photovoltaics are of great significance in the field of renewable energy. However, the narrow intrinsic absorption spectrum of organic materials hinders the full utilization of solar energy. To fabricate a highly efficient opaque solar cell, it is greatly necessary to modify the optical properties of the device to improve light absorption. In addition, the growing interest in building-integrated photovoltaics drives the development of semitransparent devices. The preparation of semitransparent solar cells with excellent performance imposes high requirements on the high efficiency and appropriate visible light transmittance of effective optical management. In this review, the recent research progress of optical management in organic photovoltaics is reviewed, including the design of light-absorbing materials, the modification of different layers, adding a lighttrapping structure, and changing the light absorption capabilities of specific materials, so as to provide strategies of how to improve the performance of organic photovoltaic devices and present the prospect of the area.

Trans‐Reflective Structural Color Filters Assisting Multifunctional‐Integrated Semitransparent Photovoltaic Window

“…An alternative way to efficiently tailor and exploit the light waves for STOPVs, is optical modulation, including one-dimensional photonic crystal (PC), dielectric mirror (DM), and microcavity (MC) structures to facilitate the light reabsorption by the active layer or to fine-tune the transmissive color. [28][29][30][31][32][33][34][35][36][37][38] Among them, Fabry-Pérot microcavity is characterized by a sandwich architecture of transparent metal/dielectric material/transparent metal, which can selectively transmit and reflect specific light via adjusting the dielectric thickness. [39][40][41] For example, the recent electrochromic supercapacitors based on Fabry-Pérot cavity could display a wide variety of fantastic patterns consisting of different, vivid colors, achieving acceptable visual aesthetics.…”

Light Management for Fullerene-Based Semitransparent Polymer Solar Cells with a Distributed Bragg Reflector

“…11,39 The second strategy involves implementing light management for ST-OPVs through the use of optical structures. 1,40 By incorporating a multilayer optical structure, photons with varying wavelengths can be selectively transmitted or reflected. 15,41 For ST-OPVs, the multilayer optical structure can be designed to reflect NIR photons, thereby enhancing power conversion efficiency (PCE) while also maintaining high transmittance in the visible range.…”

“…Although nonfullerene solar cells represented by PM6:Y6 are more efficient currently, these molecules have strong absorption in the visible region compared to OPVs based on fullerene acceptors, − which make them difficult to achieve ST-OPVs with very high visible transparency. So, considerable efforts have been devoted to developing low-band-gap organic photovoltaic materials that exhibit dominant absorption in the near-infrared (NIR) range. , The second strategy involves implementing light management for ST-OPVs through the use of optical structures. , By incorporating a multilayer optical structure, photons with varying wavelengths can be selectively transmitted or reflected. , For ST-OPVs, the multilayer optical structure can be designed to reflect NIR photons, thereby enhancing power conversion efficiency (PCE) while also maintaining high transmittance in the visible range. Distributed Bragg/aperiodic dielectric reflectors are most commonly used for light management in ST-OPVs, and they are typically deposited on the rear electrode. ,, Of note, the two strategies can be employed simultaneously without constraint.…”

Aromatic Carboxylic Acid Ligand Management for CsPbBr3 Quantum Dot Light-Emitting Solar Cells

“…CsPbBr 3 with a wide band gap ( E g ∼2.4 eV) generates a high open-circuit voltage ( V OC ) and has great potential for application in tandem solar cells as top cells. − Moreover, CsPbBr 3 QDs overcome the problem of phase instability and exhibit narrow emission linewidth and high photoluminescence quantum yield, showing huge potential in LEDs − and lasers. − A room-temperature method was reported to synthesize CsPbBr 3 nanocrystal inks, and the corresponding solar cells were fabricated, delivering an efficiency exceeding 5% and a V OC higher than 1.5 V . However, the CsPbBr 3 nanocrystals showed poor dispersibility in hexane solvent, which seriously hindered the film uniformity and the device reproducibility.…”