with thermodynamic oxygen to water conversion potential of 1.23 V (vs reversible hydrogen electrode (RHE)). [1] Especially so in recent years, platinum (Pt)-based catalysts are widely utilized as the state of the art catalyst for ORR. [2] However, they are known to suffer from ineluctable concerns with regards to scarcity, extreme cost, poor stability in long term usage and poisoning effects from methanol crossover. [3,4] The potential of rechargeable metal-air batteries (metal = Zn, Li, Al, Mg, etc.) in future energy applications can be simply revealed from its high theoretical energy density values, in the range of 1086-11 140 Wh kg -1 . [5,6] Metal anodes, such as Zn, are earth abundant, cheap, safe for handling, and environmentally benign, favoring suitability of metal-air batteries for domestic and industrial applications. [7,8] Despite the intensive research being undertaken in the field of Zn-air batteries, major degradation issues remain with regards to the following: a) degradation of cathode materials-catalyst, carbon support and binders and b) morphological degradation of Zn anode during repeated cycles. [9] Thus, in order to realize and leverage on the full potential of metal air batteries, the primary task would be to develop highly efficient and stable air cathodes that favor oxygen chemistry, mainly the ORR.Earth abundant metal-based catalysts, like metal oxides, [10] perovskites, [11] spinel type, [12] MXenes , [13,14] and mixed metal oxides [15,16] have been investigated as ORR catalysts. In addition, heteroatom-doped carbon structures containing metallic elements, like cobalt, nickel, and iron, have emerged as promising candidates to replace Pt. Despite intensive research in metal pnictogens and chalcogens over the years, there is a lack in exploration of metal-metalloids, such as amorphous metal borides for the ORR. Transition metal borides show superior oxygen evolution reaction (OER) performance in alkaline solution compared with noble metal catalysts, metal oxides, and metal alloy counterparts. [17] In contrast, transition metal borides undergo severe oxidation, limiting activities that may be derived and consequently, their ORR performance. [18] To date, only J. Ma et al [19] and K. Elumeeva et al [20] reported the usage of CoB as an ORR electrocatalyst, but the performance obtained was not satisfying with those the state-of-the-art catalysts. CoB nanosheets are expected to be highly beneficial for electrochemical applications (for example, ORR) because 1) the synthesis of metal borides by chemical reduction is fast and facile compared with the time consuming synthesis of many other Compositional and structural engineering of metal-metalloid materials can boost their electrocatalytic performance. Herein, a highly efficient and stable electrocatalytic system for the oxygen reduction reaction is obtained by creating heterointerfaces between N-doped carbon and cobalt boride nanosheets. Furthermore, a detailed investigation on the effect of annealing temperature as well as the amount of carbon ...