First-principles calculations demonstrate an exceptional decoupling of charge and thermal transport along the \textit{a}-axis in CuBiSCl2. The material achieves superior electron mobility (138 cm2/V⋅s at 300 K) through delocalized Bi-6\textit{p}/S-3\textit{p} networks while maintaining ultralow lattice thermal conductivity (0.40 W/mK at 300 K) via Cu-dominated anharmonic phonon scattering - both optimized along the same crystallographic direction. This simultaneous optimization originates from the anisotropic bonding hierarchy where [BiSCl2]n ribbons enable efficient charge transport along \textit{a}-axis, while the soft vibrational modes associated with Cu atoms strongly scatter heat-carrying phonons. The resulting high power factor (1.71 mW/mK2 at 700 K) and peak \textit{ZT} of 1.57 establish CuBiSCl2 as a model system that realizes the long-sought "phonon glass-electron crystal" paradigm through crystallographically engineered transport channels.
@article{arxiv.2504.01319,
title = {Decoupled anisotropic Charge-Phonon Transport Enables Exceptional n-Type Thermoelectric Performance in CuBiSCl$_2$},
author = {Yu Wu and Ying Chen and Shuming Zeng and Liujiang Zhou and Chenhan Liu},
journal= {arXiv preprint arXiv:2504.01319},
year = {2025}
}