The design and properties of pseudobinary alloys (PbTe)1-x-(SnTe)x with gradient composition

The pseudobinary thermoelectric alloys (PbTe)(1-x)-(SnTe)(x) (0 less than or equal to x less than or equal to 0.4) doped with 0.02 mol% Ag concentration were prepared by pressureless sintering (PS), and their properties were optimized to fit the preparation of functionally graded materials (FGM) with gradient composition. The calculation shows that the FGM can raise the maximal power output to approximately 200.0 (W m(-2)), at least 21% greater than that of the best monolithic alloys (PbTe)(0.6)-(SnTe)(0.4). The measurement shows that the maximum power output of FGM is about 175.0 (W m(-2)), and at least increases by about 16% as compared to those of any monolithic materials (PbTe)(1-x)-(SnTe)(x) (0:5 less than or equal to x less than or equal to 0.4) without or with different Ag concentration doping. (C) 2002 Elsevier Science B.V. All rights reserved.