Tin Diselenide Molecular Precursor for Solution‐Processable Thermoelectric Materials

• Published in: Angewandte Chemie International Edition 2018-12, Vol.57 (52), p.17063-17068
• Main Authors: Zhang, Yu, Liu, Yu, Lim, Khak Ho, Xing, Congcong, Li, Mengyao, Zhang, Ting, Tang, Pengyi, Arbiol, Jordi, Llorca, Jordi, Ng, Ka Ming, Ibáñez, Maria, Guardia, Pablo, Prato, Mirko, Cadavid, Doris, Cabot, Andreu
• Format: Article
• Language: English
• Subjects: Charge transport; Crystallography; Electrical resistivity; Enginyeria química; Figure of merit; Heat transport; Hot pressing; Materials termoelèctrics; modulation doping; modulation doping nanomaterial reactive ink SnSe2 thermoelectricity; nanomaterial; Nanomaterials; Nanoparticles; Nanotechnology; reactive ink; Screw dislocations; SnSe2; Thermoelectric materials; thermoelectricity; Àrees temàtiques de la UPC
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201809847

In the present work, we detail a fast and simple solution‐based method to synthesize hexagonal SnSe2 nanoplates (NPLs) and their use to produce crystallographically textured SnSe2 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 SnSe2 bulk nanomaterials obtained from the hot pressing of these SnSe2 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, SnSe2 NPLs are blended here with metal nanoparticles. The electrical conductivities of the blends are significantly improved with respect to bare SnSe2 NPLs, what translates into a three‐fold increase of the TE Figure of merit, reaching unprecedented ZT values up to 0.65. Thermoelectrics: A fast and simple solution‐based method is presented to synthesize flower‐like SnSe2 nanostructures and crystallographically textured SnSe2 nanomaterials, which display highly anisotropic charge and heat transport properties. Unprecedented thermoelectric performance of SnSe2 is achieved through modulation doping by combining SnSe2 nanoplates with metal nanoparticles.