Tellurium selenide quantum wires synthesized by pulsed laser ablation in liquids

Tellurium–selenide (Te x Se 1-x ) binary alloys are promising chalcogenide systems with tunable optoelectronic properties, yet their synthesis in quantumly confined one-dimensional forms remains limited. Here, we report the synthesis of Te x Se 1-x quantum wires (QWs) via a two-step pulsed laser ablation in liquids (PLAL) approach, enabling surfactant-free formation of alloyed nanostructures under non-equilibrium conditions. A tellurium colloid is first generated and subsequently exposed to selenium ablation, promoting in-situ alloying through repeated plasma-bubble interactions at high repetition rate. The resulting QWs exhibit an average diameter of ∼17 ± 4 nm and a length of ∼475 ± 46 nm. Structural and chemical analyses (XRD, Raman, XPS, STEM-EDX) confirm a homogeneous trigonal Te 0.25 Se 0.75 composition with no evidence of phase segregation. Photoluminescence reveals a strong emission centered at ∼2.8 ± 0.1 eV, significantly blue-shifted relative to the bulk bandgap. This optical response cannot be explained by quantum confinement alone and is instead attributed to the combined effects of spatial confinement and disorder induced defect states arising from alloying and non-equilibrium growth. Time-resolved measurements show nanosecond-scale decay (∼1.9 ns), consistent with recombination mediated by defect-related states. Mechanistically, high-repetition-rate PLAL creates a quasi-continuous reactive environment that promotes interdiffusion, suppresses phase segregation, and drives anisotropic growth along the trigonal c-axis. These results demonstrate a versatile route for one-dimensional chalcogenide nanoalloys and highlight the interplay between confinement and disorder in tailoring nanoscale optical properties.