Large-area nanofiber membrane of NIR photothermal Cs0.32WO3 for flexible and all-weather solar thermoelectric generation.

The solar thermoelectric (STE) generator is constituted by a high-thermopower thermocell and a NIR selective Cs 0.32 WO 3 -based photothermal membrane, which can provide a significant all-weather thermoelectric generation. This work demonstrates a novel strategy for STE devices with high solar-thermoelectric conversion, durability, adaptability, and low-cost, which provide an alternative resolution in terms of a continuous power supply of wearable electronics. [Display omitted] • A wearable solar thermoelectric generator with all-weather power output is prepared. • Selective NIR absorption of Cs 0.32 WO 3 benefits colouring and photothermal conversion. • Heat concentration of photothermal membrane promotes enhanced temperature gradient. • This work delivers a resolution of continuous power supply for wearable electronics. Harvesting heat or solar energy to directly generate affordable and sustainable electricity holds great promise toward both fundamental science and practical applications in self-powered wearable electronics. However, solar thermoelectric (STE) devices remain challenging in establishing a stable and significant temperature gradient (Δ T) across thermoelectric materials for cost-effective electricity generation. Herein, a wearable STE generator with all-weather and high-performance electricity generation was elaborately designed and synthesized sandwiched by a thermogalvanic cell and a large-area nanofiber membrane of Cs 0.32 WO 3 (CWO) nanoparticles with strong near-infrared (NIR) absorption. These prepared CWO membranes, which were prepared via an electrostatic spinning technique, present a high photothermal conversion efficiency of 42.7 % with no degradation after running for 10 cycles. Notably, a significant Δ T of 31.5 K across the thermoelectric modular was achieved for STE generation via the thermal concentration of these photothermal membranes under natural sunlight. Owing to the high thermopower of 2.87 mV K−1 for each p-n pair, STE generation demonstrates a maximum output voltage of 200 mV under natural solar irradiance during the time period of noon. This work explores a new strategy to achieve efficient heat management of STE devices for high electricity generation under all-weather conditions, which demonstrates great potential for self-powered wearable electronics. [ABSTRACT FROM AUTHOR]