The oxygen reduction reaction (ORR) is a key step in H₂–O₂ 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 H₂–O₂ fuel cell, in which the open circuit voltage (Voc) increased from 0.64 to 1.18 V, and the short circuit current (Jsc) 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.

This work has been financially supported by National Natural Science Foundation of China, 973 National Basic Research Program of the Ministry of Science and Technology,and the Collaborative Innovation Center of Chemistry for Energy Materials(iChEM).

Peper Link：http://onlinelibrary.wiley.com/doi/10.1002/anie.201607118/full