Rational design of 2D super holey metal carboniride leaf-like nanostructure for efficient oxygen electrocatalysis

Abstract

Highly porous and hollow non-noble metal carbonitride nanostructures featuring large surface area and active metal sites are ideal materials for energy conversion. Nevertheless, it remains challenge to synthesize such elegant architectures, since during the carbonization process, the metal clusters aggregation, shape fusion, and pore collapse normally restrict the formation of continuous yet hierarchical porosity, thereby limiting further electrochemical features. Here, we innovatively present a facial alternant two-dimensional (2D) metal-organic frameworks (MOFs) assembly strategy to rationally synthesize a super holey, hollow and shape well-defined Co-N-C nanoleaf (HP-CoNC-L). As a result, despite metal moiety doping, the hierarchal macro-/meso-/micropores interconnected hollow “nanoleaf” evolved both an extra high surface area (1380 m2 g−1) and total pore volume (1.68 cm3 g−1), over two-fold greater than currently reported Co-N-C species. In addition to the hollow structure and fascinating porous network, the intensive Co nanoparticles and abundant active sites jointly contributed to the extraordinary bifunctional catalytic reactivity towards oxygen, e.g. a small ORR/OER subtraction (ΔE = 0.64 V), hence validating the practicability of rechargeable all solid planar micro metal-air batteries.