Importance of spin‐orbit coupling on photovoltaic properties of Pb‐free vacancy ordered double perovskites halides X 2 TeY 6 ( X = Cs , Rb , and Y = I , Br , Cl ): First‐principles calculations

International Journal of Energy ResearchEarly View SHORT COMMUNICATION Importance of spin-orbit coupling on photovoltaic properties of Pb-free vacancy ordered double perovskites halides X2TeY6 (X = Cs, Rb, and Y = I, Br, Cl): First-principles calculations Smahane Dahbi, Smahane Dahbi Laboratory of Condensed Matter and Interdisciplinary Sciences, Faculty of Sciences, Mohammed V University, Rabat, MoroccoSearch for more papers by this authorNajim Tahiri, Corresponding Author Najim Tahiri tahiri.najim@gmail.com orcid.org/0000-0001-6204-1359 Laboratory of Condensed Matter and Interdisciplinary Sciences, Faculty of Sciences, Mohammed V University, Rabat, Morocco Correspondence Najim Tahiri, Laboratory of Condensed Matter and Interdisciplinary Sciences, Faculty of Sciences, Mohammed V University, Rabat, Morocco. Email: tahiri.najim@gmail.comSearch for more papers by this authorOmar El Bounagui, Omar El Bounagui Laboratory of Condensed Matter and Interdisciplinary Sciences, Faculty of Sciences, Mohammed V University, Rabat, MoroccoSearch for more papers by this authorHamid Ez-Zahraouy, Hamid Ez-Zahraouy Laboratory of Condensed Matter and Interdisciplinary Sciences, Faculty of Sciences, Mohammed V University, Rabat, MoroccoSearch for more papers by this author Smahane Dahbi, Smahane Dahbi Laboratory of Condensed Matter and Interdisciplinary Sciences, Faculty of Sciences, Mohammed V University, Rabat, MoroccoSearch for more papers by this authorNajim Tahiri, Corresponding Author Najim Tahiri tahiri.najim@gmail.com orcid.org/0000-0001-6204-1359 Laboratory of Condensed Matter and Interdisciplinary Sciences, Faculty of Sciences, Mohammed V University, Rabat, Morocco Correspondence Najim Tahiri, Laboratory of Condensed Matter and Interdisciplinary Sciences, Faculty of Sciences, Mohammed V University, Rabat, Morocco. Email: tahiri.najim@gmail.comSearch for more papers by this authorOmar El Bounagui, Omar El Bounagui Laboratory of Condensed Matter and Interdisciplinary Sciences, Faculty of Sciences, Mohammed V University, Rabat, MoroccoSearch for more papers by this authorHamid Ez-Zahraouy, Hamid Ez-Zahraouy Laboratory of Condensed Matter and Interdisciplinary Sciences, Faculty of Sciences, Mohammed V University, Rabat, MoroccoSearch for more papers by this author First published: 02 January 2022 https://doi.org/10.1002/er.7631Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Summary In this paper, the crystal structures, thermodynamic stability, electronic densities of states, band structures, and optical properties of the nontoxic Pb-free vacancy ordered double perovskites halides X2TeY6 (X = Cs, Rb, and Y = I, Br, Cl) were investigated using first-principles calculations. It was found that at Γ point, the conduction band splits into two bands upon inclusion of spin-orbit coupling (SOC) interaction for X2TeY6 compound. Besides, the highest occupied molecular orbital is unchanged for all studied compounds except that of X2TeI6, which is shifted from W to X point. Our findings appear to be well supported by the experimental data (Annalise E. Maughan et al., J Am Chem Soc. 2016;138:8453-8464). This shows a contradiction with the theoretical work found by Malak Azmat Ali et al., Int. J. Energy Res. 2020;45:8448-8455. Hence, the inclusion of SOC is crucial for the correct characterization of the electronic properties of the X2TeY6 compound. Otherwise, the absorption coefficients shift to the visible region by the substitution of Cl by Br and I ions. Thus, the excellent absorption coefficients percentages of Cs2TeI6 (62%-75%) and Rb2TeI6 (57%-76%) along the visible region, their suitable forbidden bands (1.422 eV for Cs2TeI6, and 1.469 eV for Rb2TeI6) and their high stabilities make both Cs2TeI6 and Rb2TeI6 as new potential candidates' compounds for single-junction solar cells. Early ViewOnline Version of Record before inclusion in an issue RelatedInformation