Photocatalytic Removal of the Greenhouse Gas Nitrous Oxide by Liposomal Microreactors

Abstract

Nitrous oxide (N 2 O) is a potent greenhouse and ozone-reactive gas for which emissions are growing rapidly due to increasingly intensive agriculture. Synthetic catalysts for N 2 O decomposition typically contain precious metals and/or operate at elevated temperatures driving a desire for more sustainable alternatives. Here we demonstrate self-assembly of liposomal microreactors enabling catalytic reduction of N 2 O to the climate neutral product N 2 . Photoexcitation of graphitic Ndoped carbon dots delivers electrons to encapsulated N 2 O Reductase enzymes via a lipid-soluble biomolecular wire provided by the MtrCAB protein complex. Within the microreactor, electron transfer from MtrCAB to N 2 O Reductase is facilitated by the general redox mediator methyl viologen. The liposomal microreactors use only earth-abundant elements to catalyze N 2 O removal in ambient, aqueous conditions.