Superassembling of Bi2Te3 hierarchical nanostructures for enhanced thermoelectric performance

Abstract

We describe a facile and one-step pulsed laser deposition (PLD) technique that was utilized for the first time to systematically fabricate a series of innovative Bi2Te3 superassembly-on-epitaxy bi-layer nanostructures, by uniquely coupling the upper self-assembled well-ordered Bi2Te3 hierarchical nanostructures with unusually high surface-and interface-to-volume ratios and a highly electrical conductive epitaxial bottom thin layer on insulated SiO2/Si substrates, as an emerging new class of the most advanced thermoelectric nanomaterials. The optimized power factor of the present superassembly-on-epitaxy films is one to three orders of magnitude higher than that of most Bi2Te3 nanoassemblies defined as the assemblies of nanocrystals, evidently proving the significance and potential of the present new concept and the resulting thermoelectric nanomaterials.