Cement-SnSe Thermoelectric Devices With High Seebeck Coefficients

Abstract

In this work, we present a cost-effective, scalable approach for fabricating thermoelectric (TE) generators using p-type tin selenide (SnSe) bonded in a cement matrix via a slurry mold casting technique. Traditional methods for manufacturing SnSe-based TE materials are energy-intensive and economically unfeasible. By contrast, our approach employs common Portland cement as a binder, offering a viable alternative that reduces processing time, complexity, and cost. Ball-milled SnSe is mixed with varying concentrations of cement and cast into molds for samples, resulting in dimensions of 1.5 × 1.5 × 0.75 cm3. The best-performing formulations are 0.2 wt.% cement, which exhibited a power factor of 77 µW m−1·K−2 at 800 K and the 0.3 wt.% cement sample, which has a peak ZT of 0.3 at 850 K, the highest ZT of any cement containing TE to date. A proof-of-concept thermoelectric generator (TEG) comprising six legs of SnSe-cement composite demonstrated a peak power output of ∼73 µW at 850 K. Furthermore, calculations show that using the cement-bonded SnSe to harvest industrial waste heat in a steel-making environment can yield a potential 1521.3 W m−2 of electrical energy.