Unlocking the porous, anomalous narrow band gap inorganic graphenylene-like CuO monolayer with post oxidation advantage for thermophotovoltaic and solar cell

• Published in: Surfaces and Interfaces
• Main Author: Chang Y.H.R.; Yeoh K.H.; Jiang J.; Annuar I.; Tuh M.H.; Leong S.H.; Lim T.L.; Low L.C.; Yong Y.S.
• Format: Article
• Language: English
• Published: Elsevier B.V. 2025
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85211200817&doi=10.1016%2fj.surfin.2024.105588&partnerID=40&md5=9cbad22456f8f522f0da93ee0b0a359f

In recent years, two-dimensional (2D) graphenylene analog such as hexagonal BN and SiC have been identified as promising materials for clean technology applications. This has not only resulted in the growth of the 2D group, but also sparked excitement about the potential to manipulate different characteristics without the need for strain or the introduction of faults. In this study, we investigated the potential of graphenylene-like CuO as a highly favorable material for optoelectronic purposes. Porous graphenylene was used as the architectural template for its construction. By examining the ab initio molecular dynamics (AIMD) simulations, phonon spectra, chemical-bonding analysis and elastic coefficients, the stability of the system is verified. The HSE06 calculations indicate that the non-planar CuO exhibits an unusual narrow, direct band gap (Eg) of 0.81 eV that almost fit into the optimum range of the thermophotovoltaic (TPV) requirement, with notable optoelectronic performance enabled by strong infrared-visible light absorption (attaining 105 cm−1), moderate carrier mobilities (27–135 cm2 V−1 s−1) and low exciton binding energies (0.17 eV), in addition to TPV energy conversion efficiency (η) and spectroscopic limited maximum efficiency (SLME) of 18 % and 25 %, respectively. Effect of oxidation was further elucidated by evaluating the electronic properties of O2 decorated CuO, in which we identified a favorable slight red shift post O2 exposure, improving η to 43 %. Simulations based on Poisson equation reveal an impressive power conversion efficiency (PCE) of 22.6 % and fill factor (FF) of 81.06 % for the proposed FTO/CdS/CuO/Ag architecture. The notion discussed here has the potential to facilitate the development of highly efficient TPV and PV devices that utilize 2D materials. © 2024 Elsevier B.V.