Cobalt modified two-dimensional polypyrrole synthesized in a flat nanoreactor for the catalysis of oxygen reduction

• Co-2D-Co-PPy fabricated by a flat nanoreactor is firstly used as ORR catalyst.
• The planar configuration of 2D-Co-PPy benefits the electron transfer.
• The Co–N sites induce-formed in the layers of Co-MMT are active-sites for ORR.

Developing highly efficient and low-cost electrocatalysts for the oxygen reduction reaction (ORR) is the key to the fabrication of commercially viable fuel cell devices and metal-air batteries for future energy applications. Here, we report cobalt modified polypyrrole (PPy) nanosheets as a novel non-precious metal electrocatalyst for the ORR. Cobalt modified montmorillonite (Co-MMT) is used as a flat nanoreactor to generate the PPy nanosheets with planar configuration and facilitate the formation of Co–N sites. The planar configuration of PPy benefits the electron transfer and the exposure of the Co–N active sites for the catalysis of ORR. This study opens a new way to rationally design inexpensive and environmental friendly electrocatalysts for the ORR.