Photoassisted Oxygen Reduction Reaction in H-2-O-2 Fuel Cells

摘要

The oxygen reduction reaction (ORR) is a key step in H-2-O-2 fuel cells, which, however, suffers from slow kinetics even for state-of-the-art catalysts. In this work, by making use of photocatalysis, the ORR was significantly accelerated with a polymer semiconductor (polyterthiophene). The onset potential underwent a positive shift from 0.66 to 1.34 V, and the current was enhanced by a factor of 44 at 0.6 V. The improvement was further confirmed in a proof-of-concept light-driven H-2-O-2 fuel cell, in which the open circuit voltage (V-oc) increased from 0.64 to 1.18 V, and the short circuit current (J(sc)) was doubled. This novel tandem structure combining a polymer solar cell and a fuel cell enables the simultaneous utilization of photo-and electrochemical energy, showing promising potential for applications in energy conversion and storage.