Harnessing Near-Infrared Light for Enhanced Solar Hydrogen Production from Escherichia coli Interfaced with Biocompatible Low-Bandgap Conjugated Polymer Nanosheets

The efficient conversion of solar energy into clean hydrogen fuel presents a promising pathway for sustainable energy production. However, utilizing the full solar spectrum, particularly the near-infrared (NIR) region, remains underexplored in photosynthetic biohybrid systems. In this study, biocompatible, low-bandgap conjugated polymer nanosheets (PyTT-tBAL-HAB) are developed to integrate with non-photosynthetic, non-genetically engineered Escherichia coli (E. coli) for enhanced solar-driven biological hydrogen production. The PyTT-tBAL-HAB nanosheets exhibit unique NIR light absorption properties. Integrating these nanosheets with E. coli facilitates efficient electron transfer, resulting in a 1.96-fold increase in hydrogen production rate under NIR light. Consequently, this photosynthetic biohybrid system achieves a quantum efficiency of 18.36% at 940 nm. This study demonstrates the potential of using low-bandgap conjugated polymer nanosheets as advanced photosensitizers in semi-artificial photosynthetic systems, offering a robust platform for the effective utilization of the solar spectrum.