Self-assembly of MoTe2 nanostructures and nanocomposites over centimeter-large areas via femtosecond laser

Abstract

The fabrication of patterned two-dimensional (2D) materials exhibits significant potential for advancing their electronic and optoelectronic applications. In this Letter, we demonstrate a rapid and scalable method for creating nanoscale periodic molybdenum ditelluride (MoTe2) nanostructures and mixed-dimensional heterostructures over a large area using direct femtosecond laser irradiation. Under intense femtosecond laser pulses, periodic energy deposition occurs in layered MoTe2 and subsequently induces the formation of MoTe2 periodic nanostructures. In addition, femtosecond laser ablation at a high repetition rate (1 MHz) results in the formation of numerous crystalline Te nanoparticles scattered on the surface of MoTe2 layers, creating mixed-dimensional Te/MoTe2 heterostructures. Notably, the fabrication of MoTe2 periodic nanostructures and mixed-dimensional heterostructures is driven by a self-assembled process. This technique enables the production of centimeter-scale MoTe2 periodic nanostructures and nanocomposites within 5 min, offering a cost-effective, lithography-free approach for fabricating periodically nanostructured 2D materials in large areas for practical applications in electronics, optoelectronics, catalysis, and sensing.