Investigations on morphological evolution in tellurium nanostructures

Tellurium nanostructures (TeNs) interact exclusively via van der Waals forces and exhibit a quasi-one-dimensional electronic band structure, yielding properties that differ markedly from bulk Tellurium (Te). Here, we report a facile, one-step, room-temperature wet-chemical synthesis of TeNs and systematically examine their morphological evolution. Building on Rani et al.(Appl Phys A Mater Sci Process 10.1007/s00339-022-05405-3) observation that Mo additives induce time-dependent phase transitions in Te nanotubes at 120 °C (and thermodynamic insights by Sudheer et al.(J Phys Chem C Nanomater Interfaces 127 36 18076 18088)), we extended the investigation by varying the reaction temperature (ambient to 135 °C) and reaction time. Using field-emission SEM and high-resolution TEM, we found that at 120 °C Te initially forms nanotubes which convert into nanoflakes after 6 h and then revert in consistent with findings of Rani et al.( Appl Phys A Mater Sci Process 10.1007/s00339-022-05405-3)’s report. At 135 °C, however, the intermediate flake stage is entirely suppressed, and Te nucleates and grows directly as uniform one-dimensional nanorods. FTIR, XRD, and XPS analyses confirm that at 120 °C Mo–O–Te–O and Te–Mo–Te linkages form selectively at 6 h, whereas at 135 °C full reduction proceeds without intermediate bonding rearrangements. EDX shows higher elemental Te content at 135 °C, and thermal conductivity measurements reveal that the nanorods possess enhanced thermal stability. This work thus introduces a novel, solution-based route to stable Te nanorods with improved structural and thermal properties.