CoMoS3.13 nanosheets grafted on B, N co-doped graphene nanotubes as bifunctional catalyst for efficient water electrolysis

Abstract

Transition metal sulfides have attracted intensive interests as cost-effective catalysts for water electrolysis. However, demands for their active catalytic activity towards hydrogen evolution reaction (HER), and especially oxygen evolution reaction (OER) are still urgently needed and challenging. To address this issue, we rationally select B, N co-doped graphene nanotubes (BN-CNT) as active substrate to support CoMoS3.13 nanosheets to fabricate bifunctional catalyst for overall water electrolysis. The present contribution indicates that, doped N and B species can serve as active sites to improve the HER and OER activity of transition metal sulfides. Moreover, BN-CNT substrate not only assures the edge terminated texture of CoMoS3.13 nanosheets for more active sites, but also acts as “highway” to accelerate the charge transfer for enhanced reaction kinetics. Therefore, remarkably enhanced HER and OER catalytic activities are obtained from the hybrid catalyst, including decreased overpotetnial, increased catalytic current density, improved reaction kinetics, and superior stable durability. We believed that BN-CNT could be further used to composite with other metal chalcogenides, hydroxides, or phosphides as high-performance electrocatalysts for applications in sustainable energy conversion systems.