Biohybrid Catalyst Rapidly Produces H₂

A molecular complex consisting of photosystem I (PSI) and platinum nanoparticles serves as a highly active hydrogen-production catalyst when exposed to light, according to researchers at Argonne National Laboratory who conducted the study (J. Phys. Chem. Lett., DOI: 10.1021/jz101728v). Capturing sunlight and using it to produce fuels, for example, by splitting water to generate H₂, could help reduce global dependence on fossil fuels and offer environmental benefits. Natural protein complexes such as PSI, which plays a central role in photosynthesis, efficiently mediate light harvesting and photodriven electron transfer. But exploiting PSI by coupling it to a catalytic center that facilitates H₂ production has remained challenging. Argonne’s Lisa M. Utschig, Nada M. Dimitrijevic, and coworkers devised a biohybrid system in which catalytic platinum nanoparticles latch onto PSI electrostatically. That approach is simpler and potentially more applicable than tethering the particles via a molecular wire, a strategy reported by other researchers. Control tests indicate that the PSI-Pt complex generates H₂ at a rate five times greater than the previous record-setting system, the researchers report.