Mechanical Programming of Carrier Flow by Band-Alignment Inversion in Two-Dimensional Heterostructures.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 42252626.
- Also identified by DOI 10.1021/acs.nanolett.6c02072.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Controlling the direction of photogenerated carrier transfer in two-dimensional heterostructures is a longstanding challenge for optoelectronic logic and photocatalysis. Here we show that tensile strain can drive a complete inversion of band-edge alignment in type-II transition-metal dichalcogenide/transition-metal carbide (TMDC/MXene) heterostructures, reversing the carrier transfer direction without sacrificing efficient charge separation. This unusual behavior originates from opposite orbital responses of the two sublayers: strain lowers the band edges of weakly ionic TMDCs but raises those of strongly ionic MXenes, enabling strain-driven band-alignment inversion. In WSe<sub>2</sub>/Zr<sub>2</sub>CO<sub>2</sub> heterostructures, this mechanism reverses both electron and hole transfer directions while preserving ultrafast femtosecond charge separation and nanosecond carrier lifetimes, as revealed by nonadiabatic molecular dynamics simulations. These results establish strain-driven band-alignment inversion as a general strategy for mechanically programmable control of carrier flow in van der Waals heterostructures.