Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
Browse
2 results
Search Results
Article Citation - WoS: 2Citation - Scopus: 1Shell-Shaped Active Layers for Omnidirectional Organic Photovoltaic Cells(SPIE - Society of Photo-Optical Instrumentation Engineers, 2022-10-27) Hah, DooyoungFor the employment of organic photovoltaic cells in wearable electronic systems, improvements in energy conversion efficiency and omnidirectionality (angular coverage) are highly appreciated. This study aims at those improvements by introducing shell-shaped active layers. The proposed device structures enhance light absorption and angular range through light coupling to guided modes in the active layer. Two shapes, i.e., a triangle and a semicircle, are examined for the shell cross-sections. Numerical simulation using finite-element analysis and finite-difference time-domain methods demonstrates that the devices with the triangular-shell-shaped active layers exhibit an average absorption enhancement of up to 63% for transverse electric (TE)-polarization and up to 32% for transverse magnetic (TM)-polarization when compared with the flat active layers of the same thicknesses. The average enhancements of the semicircular-shell-shaped active layers are found to be slightly lower than those values, with 60% for TE and 28% for TM. The examined structures also show good omnidirectionality with decent absorption up to an 81 deg incidence angle for the triangular-shell-shaped device and up to a 76 deg angle for the semicircular one when TM polarization is considered. These absorption enhancements and improved angular coverages make the proposed structures highly attractive for wearable electronic system applications. (c) 2022 Society of Photo-Optical InstrumentationEngineers (SPIE)Article Citation - WoS: 4Citation - Scopus: 3Hemispherical-Shell Organic Photovoltaic Cells for Absorption Enhancement and Improved Angular Coverage(SPIE - Society of Photo-Optical Instrumentation Engineers, 2024-02-14) Hah, DooyoungA hemispherical shell shape is proposed for an organic photovoltaic cell structure, aiming at enhancing both light absorption and angular coverage. Three-dimensional finite element analysis method is used to study the absorption spectra within the hemispherical-shell-shaped active layer. The study reveals that the proposed structure can result in 66% and 36% of absorption improvements compared to a flat-structured device when the incoming light is transverse electric (TE)- and transverse magnetic (TM)-polarized, respectively. It is also learned that the proposed hemispherical shell structure has absorption improvement as high as 13% (TE) and 21% (TM) when compared to the previously reported semicylindrical shell structure. The angular coverage of the proposed structure is improved as well, reaching 81 deg (TE) and 82 deg (TM), which becomes quite useful for the wearable electronics applications where the incidence angle can vary in a random manner. These improvements can be attributed to better light coupling and guiding through the active layer made possible by the hemispherical shell shape of the device. (c) 2024 Society of Photo-Optical Instrumentation Engineers (SPIE)