Exciton-Diffusion Enhanced Energy Capture in an Integrated Nanoscale Platform

Abstract

Harnessing solar energy through biologically inspired nanoscale platforms presents a promising route for sustainable energy conversion. Biohybrid systems take advantage of the design and performance of natural systems while also enabling the optimized organization of the protein components. Until now, such systems have usually been made from components of the same species, limiting the range of properties and interactions that can be generated. Here, we introduce a nanoscale platform of biomolecular films containing cross-species antenna/reaction center proteins. We demonstrated a long-range exciton diffusion of ∼200 nm through the antenna light-harvesting complex II (LHCII) from green plants and quantified the underlying diffusivity at 3 × 10^–2 μm² ns^–1 using complementary simulations. The LHCII micropattern also induced directional exciton diffusion as a crucial mechanism for enhanced energy capture, yielding a ∼30% energy transfer efficiency to the reaction center-light-harvesting complex 1 complex from purple bacteria. This platform provides a proof-of-concept for an operation-ready, hybrid energy harvesting system capable of spanning the entire visible spectrum. The integration of diverse photosynthetic proteins into biofilm platforms offers new potential for solar energy capture and conversion.