Electronic transport and optoelectronic applications of a new layered semiconductor CuTaS3.

Two-dimensional layered bi-transition metal chalcogenides with exotic physical and optoelectronic properties are becoming attractive and promising candidates for next-generation electronics and optoelectronics. Herein, we report a representative of bi-transition metal sulfide, the strip-shaped CuTaS 3 crystal, analyzing its intrinsic electrical transport properties and potential optoelectronic applications by fabricating CuTaS 3 -based devices. The time-resolved Terahertz (THz) spectroscopy (TRTS) results indicate a rapid quenching of photoconductivity in CuTaS 3 bulk within 4.1 ps photoexcitation. PL measurement and CuTaS 3 -based field effect transistors (FETs) show a typical n-type semiconducting behavior with a small, direct bandgap of 1.24 eV. Density functional theory (DFT) calculations reveal charge transfers between different atoms and phonon dispersion relations to help understand the structural and vibrational properties of CuTaS 3. A CuTaS 3 -based-phototransistor was demonstrated with a responsivity of 7.6 mA W−1 and fast photoresponse time of 0.3–0.4 s, as well as excellent photoswitching stability. Our results may pave the way for developing other layered bi-transition metal chalcogenides and implementations in electronic and optoelectronic applications. • A representative bi-transition metal sulfide, strip-shaped CuTaS 3 crystal was presented and characterized. • DFT calculations were performed for electronic properties and phonon dispersion relations of CuTaS 3. • Investigation of intrinsic electrical transport properties and optoelectronic applications for first time • Finally, we got a responsivity of 7.6 mA W−1 and a fast photoresponse time of 0.3–0.4 s. [ABSTRACT FROM AUTHOR]