Precise control of π-conjugated polymer/carbon nanotubes heterointerfaces for oxygen reduction reactions

Nitrogen-coordinated metal catalyst has been regarded as a promising candidate for precious platinum for oxygen reduction reaction (ORR). However, controlling the structure and composition of coordinated metals in heterogeneous catalysts remains a synthetic bottleneck. Here, we design and fabricate π-conjugated polymer/CNTs heterointerfaces by polymerizing Co-BTA on CNTs. Co-BTA contains abundant Co–N4 moieties and provides catalytic sites for ORR. CNT acts as a support and constructs the network for electron transport. Therefore, Co-BTA/CNT exhibits outstanding catalytic activity for ORR with comparable half-wave potential to commercial Pt/C. Furthermore, Co-BTA/CNT demonstrates better durability and methanol tolerance compared with Pt/C. Importantly, zinc-air batteries with Co-BTA/CNT have a maximum discharge power of 94.5 mW cm−2 and a high energy density of 985 Wh kg−1, superior to that with commercial Pt/C (51.5 mW cm−2, 930 Wh kg−1). This work paves a new avenue for precisely controlling nitrogen-coordinated metal catalysts for electrochemical energy conversion and storage.