Power Generation in Slope-Type Thin-Film Thermoelectric Generators by the Simple Contact of a Heat Source

To conveniently generate electric energy for next-generation smart network monitoring systems, we propose the design and fabrication of slope-type thin-film thermoelectric generators by the simple contact of a heat source. N-type Bi2Te3 films and p-type Sb2Te3 films were formed on a stainless-steel substrate employing potentiostatic electrodeposition using a nitric acid-based bath, followed by a transfer process. In order to naturally induce a temperature difference (ΔT) between the ends of the generator, slope blocks made by polydimethylsiloxane (PDMS) were prepared and then inserted between the generators and heat sources. The performance of the generators, the open circuit voltage (Voc), and the maximum output power (Pmax), were measured using PDMS slope angles as the temperature of the heat source was increased. The ΔT of the generators increased as the slope angle was increased. The generator with the highest slope angle (28°) exhibited a Voc of 7.2 mV and Pmax of 18.3 μW at ΔT of 15 K for a heat source temperature of 42 °C. Our results demonstrate the feasibility of slope-type thin-film thermoelectric generators, which can be fabricated with a low manufacturing cost.