posted on 2017-02-21, 00:00authored byYao Zheng, Yan Jiao, Yihan Zhu, Qiran Cai, Anthony Vasileff, Lu Hua Li, Yu Han, Ying Chen, Shi-Zhang Qiao
Organometallic complexes with metal–nitrogen/carbon
(M–N/C)
coordination are the most important alternatives to precious metal
catalysts for oxygen reduction and evolution reactions (ORR and OER)
in energy conversion devices. Here, we designed and developed a range
of molecule-level graphitic carbon nitride (g-C3N4) coordinated transition metals (M–C3N4) as a new generation of M–N/C catalysts for these oxygen
electrode reactions. As a proof-of-concept example, we conducted theoretical
evaluation and experimental validation on a cobalt–C3N4 catalyst with a desired molecular configuration, which
possesses comparable electrocatalytic activity to that of precious
metal benchmarks for the ORR and OER in alkaline media. The correlation
of experimental and computational results confirms that this high
activity originates from the precise M–N2 coordination
in the g-C3N4 matrix. Moreover, the reversible
ORR/OER activity trend for a wide variety of M−C3N4 complexes has been constructed to provide guidance
for the molecular design of this promising class of catalysts.