Fast phase formation of double-filled p-type skutterudites by ball-milling and hot-pressing.

Filled-skutterudites are promising mid-temperature thermoelectric materials for heat-to-electricity conversion. Traditional preparation methods need a very long time annealing (7 to 14 days) to form the right skutterudite phase. Annealing is especially critical for p-type filled-skutterudites, since Fe4Sb12 needs filler atoms to enter the cage to form a stable phase. In this work, we prepared Ce and Nd double-filled p-type skutterudite materials by directly ball-milling the quenched ingot without annealing followed by hot-pressing. The results showed that with appropriate ball-milling time, a pure p-type filled-skutterudite phase can be obtained in just 5 minutes by hot-pressing. The samples prepared in this way have the same quality as those prepared by traditional long time annealing methods, and showed ZT values above 1 between 700 and 800 K. This simple and efficient method is very useful for the preparation of many other materials that are kinetically difficult to make.

[1]  H. Ohashi,et al.  Anomalous duality of 4f electrons in filled skutterudite CeOs4Sb12. , 2009, Physical review letters.

[2]  B. Sales,et al.  FILLED SKUTTERUDITE ANTIMONIDES : ELECTRON CRYSTALS AND PHONON GLASSES , 1997 .

[3]  Qian Zhang,et al.  Thermoelectric Property Studies on Cu‐Doped n‐type CuxBi2Te2.7Se0.3 Nanocomposites , 2011 .

[4]  Gang Chen,et al.  Dramatic thermal conductivity reduction by nanostructures for large increase in thermoelectric figure-of-merit of FeSb2 , 2011 .

[5]  M. Dresselhaus,et al.  Role of phonon dispersion in studying phonon mean free paths in skutterudites , 2012 .

[6]  W. Jeitschko,et al.  LaFe4P12 with filled CoAs3‐type structure and isotypic lanthanoid–transition metal polyphosphides , 1977 .

[7]  Donald T. Morelli,et al.  Low temperature properties of the filled skutterudite CeFe4Sb12 , 1995 .

[8]  R. Horne.  Effect of Oxide Impurities on the Thermoelectric Powers and Electrical Resistivities of Bismuth, Antimony, Tellurium, and Bismuth‐Tellurium Alloys , 1959 .

[9]  C. Uher,et al.  Transport and mechanical properties of Yb-filled skutterudites , 2009 .

[10]  G. Saunders,et al.  The Seebeck coefficient and the Fermi surface of antimony single crystals , 1967 .

[11]  Ctirad Uher,et al.  p-Type skutterudites RxMyFe3CoSb12 (R, M = Ba, Ce, Nd, and Yb): Effectiveness of double-filling for the lattice thermal conductivity reduction , 2011 .

[12]  Singh,et al.  Electronic structure of Ce-filled skutterudites. , 1996, Physical review. B, Condensed matter.

[13]  C. Sekine,et al.  Micro-probed raman scattering study of ternary ruthenium phosphides with filled skutterudite-type structure , 1998 .

[14]  E. Hyer,et al.  RATIONAL SYNTHESIS OF METASTABLE SKUTTERUDITE COMPOUNDS USING MULTILAYER PRECURSORS , 1997 .

[15]  M. Kanatzidis.  Nanostructured Thermoelectrics: The New Paradigm?† , 2010 .

[16]  Edward J. Timm,et al.  Skutterudite-based thermoelectric technology for waste heat recovery: Progress towards a 1 kW generator , 2011 .

[17]  Hui Wang,et al.  Stronger phonon scattering by larger differences in atomic mass and size in p-type half-Heuslers Hf1−xTixCoSb0.8Sn0.2 , 2012 .

[18]  Miaofang Chi,et al.  Multiple-filled skutterudites: high thermoelectric figure of merit through separately optimizing electrical and thermal transports. , 2011, Journal of the American Chemical Society.

[19]  R. K. Williams,et al.  Filled Skutterudite Antimonides: A New Class of Thermoelectric Materials , 1996, Science.

[20]  I. I. Mazin,et al.  CALCULATED THERMOELECTRIC PROPERTIES OF LA-FILLED SKUTTERUDITES , 1997 .

[21]  M. Dresselhaus,et al.  High-Thermoelectric Performance of Nanostructured Bismuth Antimony Telluride Bulk Alloys , 2008, Science.

[22]  Zhifeng Ren,et al.  Enhancement of Thermoelectric Figure‐of‐Merit by a Bulk Nanostructuring Approach , 2010 .