CoTe2/NiTe2 heterojunction embedded in N-doped hollow carbon nanoboxes as high-efficient ORR/OER catalyst for rechargeable zinc-air battery

Interface engineering has been recognized as one of the most promising strategies for tuning the catalytic properties of catalysts. However, building well-defined nanointerfaces for efficient oxygen reduction/evolution reactions (ORR/OER) remains a challenge. Herein, a hollow heterostructure composed of highly-dispersed CoTe2 inside the mesoporous walls of nitrogen-doped carbon nanoboxes and uniformly-dispersed NiTe2 outside the mesoporous walls (H-CoTe2/NiTe2@NCBs) is designed via a ZIF67-involved etching-anchoring-tellurization strategy. Promising half-wave potential of 0.86 V and overpotential of 320 mV at 10 mA cm−2 are obtained by H-CoTe2/NiTe2@NCBs. The excellent ORR/OER activity of H-CoTe2/NiTe2@NCBs is ascribed to the synergistic coupling based on nanointerfaces between CoTe2 and NiTe2. Density functional theory calculations confirm that the nanointerface-based electronic coupling between CoTe2 and NiTe2 facilitates the charge transfer between two components and generates abundant catalytically active sites at the heterointerface, thereby significantly promoting the ORR/OER activities. This work provides the design principles for transitional bimetallic tellurides as bifunctional electrocatalysts.