Chromophore Driven Assembly of Gold Nanobipyramids for Plasmonic and Photothermal Enhancement toward Pyroelectric Energy Harvesting

The controlled assembly of metal nanoparticles remains a fundamental challenge in the field of nanoscience. While the ordered assembly of spherical and rod-shaped nanoparticles is well-established, gold nanobipyramids have received comparatively limited attention due to the complexities associated with their unique geometry. This study demonstrates how a BODIPY chromophore bridges adjacent gold nanobipyramids, facilitating their assembly and enhancing plasmon-molecule interactions. These interactions promote efficient photothermal conversion, causing an 18 °C temperature rise within 6 min of laser irradiation. The assembled nanobipyramids are then embedded in poly(vinyl alcohol) (PVA) films for light-harvesting, combined with polyvinylidene fluoride (PVDF) films as the pyroelectric layer. This integration boosts light-to-electricity conversion, producing open-circuit voltage and short-circuit current 5 and 12 times higher than those with pristine nanobipyramids and neat PVDF, respectively. As energy harvesting techniques emerge for low-power electronic devices, this approach offers promising potential for sustainable energy solutions and next-generation wearable technologies.