Ab initio studies of the effects of Mn and intrinsic vacancy on the electronic, optical, water splitting properties of hematite Fe2O3 monolayer

• Published in: Optical materials Vol. 148; p. 114898
• Main Authors: Wang, Shan, Ren, Jianfei, Pan, Zilong, Su, Yanan, Tian, Bowen, Zhang, Jiying, Wang, Qingbo
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2024
• Subjects: Ab initio study; Electronic property; Fe2O3 monolayer; Optical property; Electronic property; Ab initio study; Optical property; Fe2O3 monolayer
• ISSN: 0925-3467
• DOI: 10.1016/j.optmat.2024.114898

Hematite (Fe2O3) is a prevalent mineral known for its utility as an optoelectronic and photocatalytic material. It boasts abundant reserves, cost-effectiveness, and widespread use in optoelectronic and photocatalytic applications. Recently, the discovery of Fe2O3 monolayers has expanded its potential as a promising material in the same domains. The foundational attributes for its applications are rooted in its electronic and optical properties. In this study, we used density functional theory, specifically the Meta-GGA + U approach, to explore the electronic and optical properties of monolayer Fe2O3 doped with Mn and subject to Mn adsorption. Additionally, we examine the properties of Mn-doped Fe2O3 monolayers containing intrinsic vacancies. Our computational analysis reveals that the incorporation of Mn as a dopant, along with adsorption configuration, leads to a reduction in the band gap of the Fe2O3 monolayer. This effect is further observed in Mn-doped Fe2O3 monolayers containing intrinsic vacancies. Notably, the introduction of intrinsic vacancies involving both Fe and O contributes to a decrease in the band gap, concurrently enhancing the optical characteristics of the Fe2O3 monolayer. Remarkably, these alterations induce energy bands and intrinsic vacancies that improve optical properties within the visible and near-UV regions. Our investigation also proposes a potential application (water splitting) for the Fe2O3 monolayer. Through our comprehensive exploration, we not only underscore the promising prospects of Mn-doped and -adsorbed Fe2O3 monolayers in future applications but also catalyze further research endeavors in this domain. •SCAN Meta-GGA plus U method was used to guarantee the accuracy and efficiency of this study.•Mn and intrinsic vacancy were used to modulate the electronic and optical properties in Fe2O3 monolayer.•Mn-adsorbed Fe2O3 and (Fe,Mn)2O3 monolayer with O vacancy performs better in the solar energy region.•Mn modified Fe2O3 monolayer can serve as a potential platform for photoelectric devices, photocatalyst.