Periodic DLC Interlayer-Functionalized Bi-Sb-Te-Based Nanostructures: A Novel Concept for Building Heterogenized Superarchitectures with Enhanced Thermoelectric Performance.

According to the innovative design concept of omnidirectional quasi-order hetero-nanocomposites proposed for potentially realizing high thermoelectric performance, a series of superarchitectures consisting of longitudinally periodic diamond-like carbon (DLC) interlayers in latitudinally well-aligned Bi-Sb-Te (BST)-based nanostructures were successfully demonstrated for the first time using dual-beam pulsed laser deposition. This work confirmed that the periodic appearance of DLC is a practical approach to instantly resetting the BST deposition into another new crystal growth cycle. The optimized Seebeck coefficient of ∼500 µV K-1 and the corresponding power factor of ∼40 µW cm-1 K-2 achieved are comparable to or higher than the reported values for BST or BST-based nanocomposites, which evidently originated from the periodically added DLC, as clarified in the Pisarenko plot. In addition, the DLC additives effectively reduce the thermal transport as qualitatively evidenced by micro-Raman characterizations.