Multienergy Codriven Electron Transfer Across the Nano-Bio Interface for Efficient Photobiocatalysis.

Abstract

Integrating biocatalysis with nanophotocatalysis provides a promising pathway to address the knotty environmental and energy problems. However, energy loss during the transfer of extracellular electrons across the nano-bio interface seriously limits the efficiency of whole-cell-based photobiocatalytic systems. Herein, we demonstrate an integrated multienergy codriven reaction platform containing BaTiO₃ nanoparticles (BTO) for harvesting mechanical energy from flowing water to elevate the interfacial electric field, BiVO₄ quantum dots (BQD) for harvesting light energy to generate photocarriers, and <i>Geobacter sulfurreducens</i> (<i>GS</i>) for accepting photoelectrons to accomplish the biocatalytic reactions. The synergism between the piezoelectric and photoelectric fields significantly promotes the cross-membrane transport of photoelectrons, contributing to enhanced acetate metabolism, electron transfer, and energy synthesis of <i>GS</i> microbes. Such well-designed BQD/BTO-<i>GS</i> hybrids result in the simultaneous degradation of organic contaminants and detoxification of heavy metals in water with approximately 100% treatment efficiency. The rates of tetracycline (TC) oxidation and Cr(VI) reduction are determined to be 32.8 and 9.58 times higher than that of <i>GS</i> biocatalysis, respectively. Our photobiocatalytic platform exhibits an exceptional apparent quantum yield of 15.54% at 400 nm, exceeding those of most reported abiotic-biotic photobiocatalytic systems. Further investigation verifies the extensibility of our multienergy codriven strategy to the other nano-bio hybrids for enhancing the biocatalytic efficiencies (such as methanogenesis, CO₂ fixation, and denitrification), thus offering an inspiring platform for energy and environmental applications. This work not only presents crucial insights into the mechanism of the water-energy nexus but also provides a paradigm for the construction of sustainable reaction systems via multienergy harnessing.