Facile and controllable preparation of tellurium nanocrystals by laser irradiation

We report a facile and controllable method for fabricating Te nanocrystals (NCs) with tunable photoluminescence from hydrothermally grown Te thin flakes using laser irradiation. The formation of Te NCs is attributed to the vaporization of Te caused by local heat from the laser and rapid recrystallization on the substrate. Moreover, the size of the Te NCs can be tuned according to the heat distribution around the laser spot; thus, photoluminescence covering a broad visible spectrum is observed by the quantum size effect. Our work provides a new strategy to synthesize Te NCs as visible-light absorbers or emitters for integrated optoelectronic and photonic nanodevices.