High-Temperature Photoluminescence in Colloidal “Quasi”2D Materials

The recent development of quasi-two-dimensional (2D) semiconducting nanomaterials [nanoplatelets (NPLs)] prepared through solution-based chemistry has attracted significant attention in the field of color conversion materials. Herein, we demonstrate the efficient high-temperature photoluminescence of the as-prepared cadmium telluride NPLs from 300 to 500 K with visually observable emission at temperatures as high as 500 K. Indeed, the thermal-emission quenching of the as-prepared NPLs in solution was found to be not only reversible following thermal cycling up to 475 K, but also comparable to more chemically complex core/shell nanostructures. To the best of our knowledge, this is the first example of the as-synthesized colloidal nanoparticles capable of high-temperature photoluminescence. This discovery highlights previously unexplored emission properties of NPLs that have the potential to be utilized for the efficient design of high-quality light emitters.