Biomass-derived solar-to-thermal materials: promising energy absorbers to convert light to mechanical motion

Abstract

Photothermal materials are very important for converting light energy into mechanical motion but the fabrication of efficient, cheap, easily prepared and green light-to-thermal materials in a convenient and green manner, and at lower cost, remains a challenge. To address this issue, we have now developed an efficient, cheap and easily prepared solar-to-thermal material that can be fabricated from extracts of larch bark. The larch bark extracts (LBE) were readily transformed into a solar-to-thermal material (LBF) by coordination with ferric (Fe³⁺) ions at room temperature on a large scale (100 g level). LBF showed a stable photothermal effect, with comparable efficiency to the classical solar-to-thermal material, reduced graphene oxide (rGO). As a demonstration of the utility of LBF, it was successfully used to drive a Stirling engine under standard 1 sun irradiation (100 mW cm⁻²). Since Stirling engines have great potential in the energy area and the as-prepared LBF could be prepared on a large scale, this work is expected to provide an efficient solution to clean and sustainable energy.