Thermoelectric converter with stepwise legs for high energy conversion efficiency

Achieving high thermoelectric conversion efficiency in Bi2Te3-based stepwise legs through bandgap tuning and chemical potential engineering

“…The proposed approach was successfully implemented by us for the development of a Bi 2 Te 3 -based thermoelectric stepwise converter. 45 The estimated maximum efficiency of the converter reaches 10.1%, while the experimental efficiency of 8.5% is somewhat lower due to the contact resistance and heat loss during measurements. Nevertheless, this value is still higher by 1.5–2 times than the efficiency of the low-temperature commercial generator thermoelectric modules 48,49 and 1.2 times higher compared with the measured performance of the stepwise generator module based on Bi 2 Te 3 -materials, which is reported in ref.…”

“…7c) while the origins of the mentioned effects are the contact resistance on the thermoelectric layer junction, heat losses from the lateral leg surface that occurred during the measurement through the thermal insulation (see Fig. S2 in the ESI†), 45 and the uncertainty of the material properties which was used during FEM calculation.…”

“…To provide the maximum energy conversion efficiency, the optimal height of the layers was determined according to expressions (S6) and (S7) 45 in the ESI. † The input parameters applied for numerical simulation are given in Table S1 (ESI †).…”

“…7c) while the origins of the mentioned effects are the contact resistance on the thermoelectric layer junction, heat losses from the lateral leg surface that occurred during the measurement through the thermal insulation (see Fig. S2 in the ESI †), 45 and the uncertainty of the material properties which was used during FEM calculation. As a result of the effectively engineered bandgap and chemical potential of the developed Bi 2 Te 3 -based thermoelectric materials, the fabricated homogeneous unilegs show a slightly higher performance compared with the commercial material unilegs.…”