Enhancement of color and photovoltaic performance of semi-transparent organic solar cell via fine-tuned 1D photonic crystal

Abstract

Semi-transparent organic solar cells’ (ST-OSCs) photovoltaic and high optical performance parameters are evaluated in innovative applications such as power-generating windows for buildings, automobiles, and aesthetic designs in architectural and industrial products. These parameters require the precision design of structures that optimize optical properties in the visible region and aim to achieve the required photon harvest in UV and IR. These designs can be realized by integrating wavelength-selective photonics-based systems into ST-OSC to increase localized absorption in wavelengths greater than 600 nm and NIR and provide modifiable optical properties. In this study, methodologically, we followed highly detailed light management engineering and transfer matrix method-based theoretical and experimental approaches. We discussed the optimal structures by evaluating color, color rendering index, correlated color temperature, and photovoltaic performances for ST-OSCs, including one-dimensional photonic crystal (1D-PC) designed at different resonance wavelengths (λB) and periods. Finally, by integrating fine-tuned (MgF2/MoO3)N 1D-PC, we report the inherently dark purple-red color of the P3HT:PCBM bulk-heterojunction-based ST-OSC neutralizes with the optimal state was 0.3248 and 0.3733 by adjusting close to the Planckian locus. We also enhanced short current density from 5.77 mA/cm2 to 6.12 mA/cm2 and PCE were increased by 7.34% from 1.77% to 1.90% designed for the N = 4 period and λB = 700 nm.

In-depth analysis on PTB7 based semi-transparent solar cell employing MoO3/Ag/WO3 contact for advanced optical performance and light utilization

“…Therefore, OSCs have the potential to be fabricated as efficient, ultra-thin, and hence ST 4 – 6 . Due to the diversity in organic materials, ST-OSCs can be produced in various colours 4 , 5 , 7 . ST-OSCs can be suitable for aesthetic decorative products and can be used in various building architectures and industrial applications that can be integrated into windows.…”

“…The design of ST-OSCs aims to absorb electromagnetic radiation outside the visible region optimally and to be as transparent as possible outside this range 8 , 9 . For this purpose, new donor and acceptor molecules with narrow band gaps have been developed to enhance the absorption of near-infrared (NIR) regions and ST-OSCs have been optimized by designing new transparent conductive films or optical coupling layers to modulate light transmission 5 – 7 , 10 , 11 . Recent years have seen tremendous progress in ST-OSCs: PCEs have been improved from 5% to over 13%, while high AVTs of over 25% have been maintained 12 , 13 .…”

“…Integrating different photonic-based systems into the solar cell (SC) structure without modifying the structure of the organic material forming the active region in ST-OSCs also enables the achievement of ST requirements 6 . For ST, dielectric/metal/dielectric (DMD) transparent contact designs with high optical transmittance and electrical conductivity, low turbidity, excellent flexibility, easy fabrication and great compatibility with different substrates can be used 6 , 7 , 14 – 16 . In the DMD design, a thin metal material is sandwiched between two anti-reflective dielectrics, and the thickness of these layers can modify the optical properties.…”

“…This can adversely affect photovoltaic performance. For that reason, it is quite a functional approach to modify the propagation of the electromagnetic wave in the ST device without modifying the active organic material 6 , 7 , 14 – 16 . For this purpose, approaches based on light management engineering have been used to optimize the optical properties of ST-OSC 18 – 20 .…”

“…For this purpose, approaches based on light management engineering have been used to optimize the optical properties of ST-OSC 18 – 20 . Among these approaches, it is rather advantageous to use Transfer Matrix Method (TMM) for enhanced and modifiable optical properties 4 , 6 , 7 , 14 , 21 .…”