Conferring supramolecular guanosine gel nanofiber with ZIF-67 for high-performance oxygen reduction catalysis in rechargeable zinc–air batteries

Nanostructured gels have emerged as a unique material platform for energy-related applications and have been mainly focused on polymer gels in recent years. We developed a coordination-driven hierarchical assembly strategy for the general exploration of robustness supramolecular gel (SMG) materials as metal-organic framework (MOF) supports for further development of high efficiency oxygen reduction reaction electrocatalysts for rechargeable Zn–air batteries. As the first example of SMG/MOF composites, guanosine SMG (GSMG) fibres were modified by terpyridine ligands, cross-linked by Zn (II), and then anchored in-situwith ZIF-67 polyhedra to produce a special ZIF-67/Zn-GSMG heterostructure enriched in heteroatoms (B, N, C, Co, and Zn) and with a continuous rigid skeleton. Pyrolysis yielded cobalt-embedded porous carbon polyhedra/B,N dual-doped carbon nanofibers with superior oxygen reduction reaction activity, showing an exceptional potential for applications in rechargeable Zn–air batteries. The present work provides a new material platform for promising future design of functional multicomponent composites.