The exploration of cheap, efficient, and durable bifunctional electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is highly desired to push forward the commercialization of rechargeable metal–air batteries. Here, bifunctional ORR/OER electrocatalysts based on CoxP (0 < x < 2, i.e., Co2P, Co2P/CoP mixture, and CoP) nanoparticles (NPs) anchored on N,P‐doped carbon framework (CoxP@NPC) are developed via one‐step carbonization of the mixture of as‐synthesized ZIF‐67 and melamine–phytic acid supermolecular aggregate (MPSA). The stoichiometric ratio of resultant CoxP NPs can be rationally designed by adjusting the introduced ratio of ZIF‐67 to MPSA, enabling their fabrication in a controlled manner. It is found that the as‐synthesized Co2P@NPC exhibits the best bifunctional ORR/OER activity among the CoxP@NPC analogues, with a reversible oxygen electrode index (ΔE = Ej10 − E1/2) down to ~0.75 V. The constructed Zn–air battery based on Co2P@NPC delivers a peak power density of 157 mW cm−2 and an excellent charge‐discharge stability with negligible voltage decay for 140 h at 10 mA cm−2, superior to those based on Pt/C+RuO2 and most CoxP‐based electrodes ever reported.

Fabrication of amorphous electrocatalysts without noble metals for cost-effective full water splitting is highly desired but remains a substantial challenge. In the present work, we report a facile strategy for exploring integrated bifunctional electrocatalysts based on amorphous cobalt/nickel sulfide nanoflake arrays self-supported on carbon cloth, by tailoring competitive coordination of metal ions between glucose and 2-aminoterephthalic acid. Ultrahigh dispersion of binary metal active sites with balanced atomic distribution enables the optimization of catalytic properties for both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) in an alkaline solution. The obtained catalyst exhibits remarkably enhanced OER and HER activities as compared with its oxide counterpart and analogues with different Co/Ni ratios. It requires overpotentials of 296 and 192 mV to deliver a current density of 10 mA cm −2 for the OER and HER, respectively; it retains 96.6 and 96.9% activity after 32 h of OER and 36 h of HER tests at 10 mA cm −2 , respectively. As directly used an anode and a cathode in an alkaline electrolyzer, a low cell voltage of 1.60 V could endow a water splitting current of 10 mA cm −2 , outperforming the benchmark RuO 2 and Pt/C-based electrolyzer at 1.72 V@10 mA cm −2 . The current synthetic strategy may provide more opportunities for the design and direct synthesis of amorphous catalysts for overall water splitting and beyond.

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