Photothermal effects control ultrafast charge transport in titanium carbide MXenes.

ABSTRACT: Titanium carbide MXene (Ti₃C₂Tₓ) is an emerging metallic material with promise for (opto)electronics and thermal management. Yet how photoexcitation-particularly via photogenerated thermal energy-modifies its charge carrier dynamics remains poorly understood. By combining time-resolved terahertz spectroscopy and transient reflectance measurements, we reveal a long-lived, photo-induced suppression of conductivity, which we attribute to efficient lattice heating and slow heat dissipation in Ti₃C₂T_x. A systematic variation of pump photon energy reveals that this 'negative' photoconductivity can equivalently be induced by lattice temperature increases, indicating a thermal origin. Repetition-rate-dependent transient reflectance measurements further show residual heat persisting over

SUBMITTER: Zheng W 

PROVIDER: S-EPMC12858860 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature