Phys.org May 16, 2024
Electronic band convergence can have a beneficial impact on thermoelectric performance, but finding the right band-converged compositions is still time-consuming. A team of researchers in the US (University of Houston, Rice University) proposed a method for designing a series of compositions with simultaneous band convergence in the high-entropy YbxCa1−xMgyZn2−ySb2 material by zeroing the weighted sum of crystal-field splitting energies of the parent compounds. They found that such compositions have both larger power factors and lower thermal conductivities and that one of them exhibited a large thermoelectric figure of merit value in comparison with to other p-type Zintls and high stability both thermally and temporally. They assembled an all-Zintl single-stage module, nontoxic and free of tellurium, that demonstrated an exceptional heat-to-electricity conversion efficiency exceeding 10% at a temperature difference of 475 kelvin… read more. TECHNICAL ARTICLE
The research team’s homemade energy conversion efficiency measurement device… Credit: University of Houston