AUTHOR=Sun Pengju , Gao Qilong , Liu Junzhe , Liang Erjun , Sun Qiang TITLE=Theoretical Study of Abnormal Thermal Expansion of CuSCN and Effect on Electronic Structure JOURNAL=Frontiers in Materials VOLUME=Volume 8 - 2021 YEAR=2021 URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2021.712395 DOI=10.3389/fmats.2021.712395 ISSN=2296-8016 ABSTRACT=
CuSCN, as a new type of inorganic hole-transporting semiconductor with a wide bandgap (>3.4 eV), is attracting much attention in the fabrication of perovskite solar cells. In this article, by using first-principles density functional theory (DFT) and the quasi-harmonic approximation (QHA) approach, we have studied lattice dynamics and abnormal thermal expansion of the system, including α- and β-CuSCN phases. The influence of the abnormal thermal expansion of the lattice on the electronic structure, especially on the bandgap of the system, was explored and discussed. We found that due to the shearing modes and the three acoustic modes along the direction of the