Solar spectral splitting for improved photosynthetic yield and energy polygeneration

Spectral splitting is a promising strategy for wavelength-selective solar energy harvesting, offering the potential to combine photosynthesis with artificial solar technologies for higher hybrid efficiencies. Despite this potential, the photosynthetic performance and biomass production of plants under split sunlight has remained unclear. Photosynthetic organisms under full sunlight must dissipate excess absorbed light energy as heat, resulting in suboptimal photosynthetic efficiency. Here, we show that solar spectral splitting can enhance photosynthesis and yield while utilizing excess sunlight for energy polygeneration. Specifically, we observed increased electron transport rate (22 %), daily leaf photosynthetic CO2 uptake (12 %), and plant biomass productivity (up to 136 %) under the selected solar spectral bands, largely due to decreased photoinhibition and improved stomatal conductance. The theoretical limit and practical guideline for photovoltaic (PV) efficiency under complementary spectral bands were ∼22.5 % and ∼14.6 %, respectively, highlighting the substantial potential for energy production. This study provides a basis for the design and application of spectral splitting energy systems on agricultural lands, which not only encompasses the concept of sharing the land or the solar spectrum, but also presents an effective strategy for enhancing crop production. •Ideal wavelength selectivity, scalable and economical sunlight splitting method.•Photosynthetic performance and physiological mechanisms are thoroughly investigated under split sunlight.•In-situ photosynthetic measurements were emphasized.•The spectral-splitting strategy can release plant photoprotection and increase yield.•High potential for energy co-production and hybrid solar energy conversion efficiency.