title: Highly Porous Thermoelectric Nanocomposites with Low Thermal Conductivity and High Figure of Merit from Large-Scale Solution-Synthesized Bi2Te2.5Se0.5Hollow Nanostructures.
abstract: To enhance the performance of thermoelectric materials and enable access to their widespread applications, it is beneficial yet challenging to synthesize hollow nanostructures in large quantities, with high porosity, low thermal conductivity (κ) and excellent figure of merit (z T). Herein we report a scalable (ca. 11.0 g per batch) and low-temperature colloidal processing route for Bi2Te2.5Se0.5hollow nanostructures. They are sintered into porous, bulk nanocomposites (phi 10 mm×h 10 mm) with low κ (0.48 W m-1K-1) and the highest z T (1.18) among state-of-the-art Bi2Te3-xSexmaterilas. Additional benefits of the unprecedented low relative density (68-77 %) are the large demand reduction of raw materials and the improved portability. This method can be adopted to fabricate other porous phase-transition and thermoelectric chalcogenide materials and will pave the way for the implementation of hollow nanostructures in other fields.
authors.affiliation: Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, 50011, USA.|Ames Laboratory, Department of Energy, Ames, IA, 50011, USA.
authors.forename: Biao
authors.initials: B
authors.lastname: Xu
authors.affiliation: Department of Mechanical Engineering, Purdue University, West Lafayette, IN, 47907, USA.
authors.forename: Tianli
authors.initials: T
authors.lastname: Feng
authors.affiliation: Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA.
authors.forename: Matthias T
authors.initials: MT
authors.lastname: Agne
authors.affiliation: Ames Laboratory, Department of Energy, Ames, IA, 50011, USA.
authors.forename: Lin
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Department of Mechanical Engineering, Purdue University, West Lafayette, IN, 47907, USA.
authors.forename: Xiulin
authors.initials: X
authors.lastname: Ruan
authors.affiliation: Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA.
authors.forename: G Jeffery
authors.initials: GJ
authors.lastname: Snyder
authors.affiliation: Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, 50011, USA.|Ames Laboratory, Department of Energy, Ames, IA, 50011, USA.
authors.forename: Yue
authors.initials: Y
authors.lastname: Wu
keywords: Kirkendall effect; hollow nanostructures; porous nanocomposites; thermal conductivity; thermoelectric materials