Tile-shaped thermoelectric devices for solar energy harvesting and fire warning in oriental ancient architectures

Thermoelectric (TE) materials, owing to their capability of direct heat-to-electricity interconversions, hold great potential in constructing smart buildings. However, reports on their integration into smart buildings remain scarce. In this work, we prepared biobased composite TE films. Their excellent photothermal conversion capability facilitates efficient absorption of solar energy and conversion into heat, establishing a large and stable temperature gradient, thereby synergistically achieving higher TE performance. Inspired by the unique overlapping and interlocking design of tiles in typical Chinese and oriental ancient architectures, where the curved tile surface enhances solar capture and the formed porous structures ensures efficient heat sink, we ingeniously designed and fabricated tile-shaped TE devices. Benefiting from the film’s photothermal effect, the prepared devices achieve a large temperature difference of nearly 60 K under solar irradiation. A device consisting of 20 TE legs generates an output voltage of 60 mV and a maximum output power of 11.9 µW, demonstrating excellent building-integrated TE energy harvesting performance. Furthermore, the TE system exhibits rapid fire warning capability, thereby providing fire protection for buildings. This work not only opens a novel avenue for achieving simultaneous harvesting of solar energy and self-powered fire warning, but also provides pioneering insights into green smart buildings and the protection of ancient architectures and cultural relics.