Investigations of optoelectronic properties of novel ZnO monolayers: A first-principles study

• Published in: Materials science & engineering. B, Solid-state materials for advanced technology Solid-state materials for advanced technology, 2021-03, Vol.265, p.115043, Article 115043
• Main Authors: Ul Haq, Bakhtiar, AlFaify, S., Alrebdi, Tahani A., Ahmed, R., Al-Qaisi, Samah, M. Taib, M.F., Naz, Gul, Zahra, Sarwat
• Format: Article
• Language: English
• Subjects: Electronic structure calculations; Energy gap; First principles; Incident light; Monolayers; Optical spectra; Optoelectronic devices; Optoelectronics; Photovoltaic cells; Two dimensional materials; Zinc oxide; Zincblende; ZnO
• ISSN: 0921-5107; 1873-4944
• DOI: 10.1016/j.mseb.2021.115043

•Devising of ZnO monolayers from zinc-blende and 5–5 structures.•Investigations of energetic stability from first-principles approach.•Investigations of the electronic band structures and optical spectra.•Transparent Direct bandgap semiconductors.•Highly absorbent of electromagnetic radiations. The development of non-toxic and low-cost two-dimensional materials has received considerable interest for applications in cutting-edge technologies. In this study, we report the devising of two types of ZnO monolayers for optoelectronic applications using the first-principles approach. These ZnO monolayers are originated from the zinc-blende (zb) and 5–5 phases of ZnO and are found to exhibit equivalent energetic stability as their bulk counterparts. The ZnO monolayer derived from zb-phase (ZnO(zb)) exhibits a narrow bandgap of magnitude 0.142 eV determined with Tran-Blaha modified Becke Johnson (TB-mBJ) exchange potential, whereas the monolayer derived from 5 to 5 phase (ZnO(5–5)) exhibits a relatively larger energy gap of magnitude 2.150 eV. The optical absorption in these monolayers approaches as high as 31.05 × 104 cm−1 for single-layered ZnO(zb) and 55.98 × 104 cm−1 for ZnO(5–5) monolayer. Further analysis of optical spectra demonstrated relatively weak reflectance of incident light by these monolayers and are found of transparent nature over a wide range of the solar spectrum. Overall, they demonstrate interesting electronic and optical features and are believed to find suitable applications in optoelectronic devices.