Tin Diselenide Molecular Precursor for Solution-Processable Thermoelectric Materials.

In the present work, we detail a fast and simple solution-based method to synthesize hexagonal SnSe nanoplates (NPLs) and their use to produce crystallographically textured SnSe nanomaterials. We also demonstrate that the same strategy can be used to produce orthorhombic SnSe nanostructures and nanomaterials. NPLs are grown through a screw dislocation-driven mechanism. This mechanism typically results in pyramidal structures, but we demonstrate here that the growth from multiple dislocations results in flower-like structures. Crystallographically textured SnSe bulk nanomaterials obtained from the hot pressing of these SnSe structures display highly anisotropic charge and heat transport properties and thermoelectric (TE) figures of merit limited by relatively low electrical conductivities. To improve this parameter, SnSe NPLs are blended here with metal nanoparticles. The electrical conductivities of the blends are significantly improved with respect to bare SnSe NPLs, what translates into a three-fold increase of the TE Figure of merit, reaching unprecedented ZT values up to 0.65.