The impacts of dopants on the small polaron mobility and conductivity in hematite – the role of disorder
Mingpeng Chen, Andrew Grieder, Tyler J. Smart, Kiley Mayford, Samuel McNair, Anica Pinongcos, Samuel Eisenberg, F. Bridges, Yat Li, Yuan Ping
Abstract
the more stretched the Fe-Fe pairs are compared to the pristine systems, the lower the carrier mobility will be. Therefore, elements which limit the distortion of Fe-Fe pair distances from pristine are more desired for higher carrier mobility in hematite. The calculated local structure and pair distribution functions of the doped systems have remarkable agreement with the experimental EXAFS measurements on hematite nanowires, which further validates our first-principles predictions. Our work revealed how dopants impact the carrier mobility and electrical conductivity of hematite and provided practical guidelines to experimentalists on the choice of dopants for the optimal electrical conductivity of hematite and the performance of hematite-based devices.