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arXiv · 2112.08062

Stacking polymorphism in PtSe$_2$ drastically affects its electromechanical properties

Roman Kempt·Sebastian Lukas·Oliver Hartwig·Maximilian Prechtl·Agnieszka Kuc·Thomas Brumme·Sha Li·Daniel Neumaier·Max C. Lemme·Georg Duesberg·Thomas Heine
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Abstract

PtSe$_2$ is one of the most promising materials for the next generation of piezoresistive sensors. However, the large-scale synthesis of homogeneous thin films with reproducible electromechanical properties is challenging due to polycrystallinity. We show that stacking phases other than the AA-stacking in the 1T phase become thermodynamically available at elevated temperatures. We show that these can make up a significant fraction in a polycrystalline thin film and discuss methods to characterize these stacking phases. Lastly, we estimate their gauge factors, which vary strongly and significantly impact the performance of a nanoelectromechanical device.

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Roman Kempt, Sebastian Lukas, Oliver Hartwig, Maximilian Prechtl, Agnieszka Kuc, Thomas Brumme, Sha Li, Daniel Neumaier, Max C. Lemme, Georg Duesberg, Thomas Heine. 2021-12-15. Stacking polymorphism in PtSe$_2$ drastically affects its electromechanical properties. https://arxiv.org/abs/2112.08062

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