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arXiv · 2602.04327

Dynamics of Long-lived Carriers in Molybdenum Carbide Nanosheets

Xiangyu Zhu·Zhong Wang·Tao Li·Xi Wang·Zheng Zhang·Chunlong Hu·Kaifu Huo·Wenxi Liang
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Abstract

Molybdenum carbide (MoC) is a promising candidate for substituting expensive platinum-group metals in many applications owing to its low cost and excellent properties, therefore a comprehensive understanding of its carrier dynamics is demanded for advancing the synthesis strategy and implementation of MoC. In this work, the carrier relaxation in MoC nanosheets is investigated by combining the femtosecond transient reflection spectroscopy with the first-principles calculations. The measured processes of electron-electron, electron-phonon, and phonon-phonon scattering show significantly longer lifetimes compared to those of other transition metal carbides. Through the analysis of calculated phonon dispersion, the nanosecond carrier lifetime is explained by the restricted phonon decay pathways, which is induced by the large mass difference between Mo and C atoms. The observed slow carrier cooling rate in our study offers a straightforward approach for effectively utilizing hot carriers, which is expected to improve the performance of photothermal and photovoltaic devices.

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Xiangyu Zhu, Zhong Wang, Tao Li, Xi Wang, Zheng Zhang, Chunlong Hu, Kaifu Huo, Wenxi Liang. 2026-02-04. Dynamics of Long-lived Carriers in Molybdenum Carbide Nanosheets. https://arxiv.org/abs/2602.04327

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