The “bionic leaf” device that Chong was developing in Prof. Dan Nocera’s lab at Harvard extends the range of molecules that it can handle. Beyond the efficient CO₂-fixing device that was reported last year in Science, now we applied a diazotrophic bacterium to fix N₂ and demonstrated the use of bio-fertilizer generated by electricity. This work is published online in PNAS this week, of which Chong and Kelsey are co-first authors.