Enhanced Solar-Driven Thermoelectric Power Generation and Water Desalination Via Hydrothermally Synthesized Degenerately Doped Copper Selenide Nanocrystals Composited with Polydimethylsiloxane

Abstract

In this study, we developed novel composites of degenerately doped copper selenide and polydimethylsiloxane (DDCS/PDMS) that efficiently harness a wide range of solar light for both electricity generation and water purification. The DDCS nanocrystals possess remarkable optical absorption capabilities across the near-infrared (NIR) solar spectrum, leading to enhanced photothermal effects. Within the DDCS/PDMS composite, this results in remarkable light-to-heat conversion, sustaining a consistent surface temperature of 51.5°C in contrast to the 39.8°C exhibited by bare PDMS when subjected to standard 1 sun intensity for 3 minutes, and leveraging its exceptional photothermal characteristics, the composite demonstrated noteworthy thermoelectric power generation, achieving 95mV, while pristine PDMS only managed 49mV under 1 sun conditions. Moreover, the DDCS/PDMS foam demonstrated outstanding solar-to-vapor performance, achieving a rate of 1.71 Kg m-2 h-1 with an efficiency of 91.5% under equivalent sunlight exposure. Remarkably, the versatile DDCS/PDMS foam effectively demonstrated its capability in seawater desalination, achieving an efficiency exceeding 80% even under the most challenging conditions. This study uncovers the compelling potential of solar-thermal energy utilization and introduces an innovative approach for solar-driven water purification and power generation. By addressing the challenges of sustainable energy and clean water provision, these findings offer a promising avenue forward.

Keywords: Copper selenide, plasmonic nanocrystals, polymer nanocomposites, thermoelectric power generation, interfacial water evaporation