Exploring Material Properties and Device Output Performance of a Miniaturized Flexible Thermoelectric Generator Using Scalable Synthesis of Bi2Se3 Nanoflakes

Abstract

Environmental heat-to-electric energy conversion presents a promising solution for powering sensors in wearable and portable devices. However, the availability of near-room temperature thermoelectric (TE) materials is highly limited, posing a significant challenge in this field. Bi2Se3, as a room-temperature TE material, has attracted much attention. Here, we demonstrate a large-scale synthesis of Bi2Se3 nanoflakes used for the microflexible TE generator. A high-performance micro-TE generator module, utilizing a flexible printed circuit, has been designed and fabricated through the process of screen printing. The TE generator configuration comprises five pairs of PN TE legs. The p-type TE leg utilizes commercially available Sb2Te3 powder, while the n-type TE leg employs Bi2Se3 nanoflakes synthesized in this study. For comparative purposes, we also incorporate commercially available Bi2Se3 powder as an alternative n-type TE leg. The optimal performance of the single-layer microflexible TE generator, employing Bi2Se3 nanoflakes as the active material, is achieved when operating at a temperature differential of 109.5 K, the open-circuit voltage (VOC) is 0.11 V, the short circuit current (ISC) is 0.34 mA, and the maximum output power (PMAX) is 9.5 μW, much higher than the generator consisting of commercial Bi2Se3 powder, which is expected to provide an energy supply for flexible electronic devices.