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Herein, Fe-phthalocyanine-based conjugated microporous polymer (Fe-Phth-CMP) coated metal organic framework (ZIF-67) composites, namely Fe-Phth-CMP@ZIF-67, were facilely prepared via a rational and effective solid-phase synthesis method, in which, ZIF-67 worked as both precursors and templates. Upon carbonization, these special composites, with controllable morphology similar to ZIF-67 and adjustable Fe/Co molar ratio, can be further converted into N-doped porous carbons embedded with highly dispersed FeCo alloy and Fe/Co–N active sites. The optimal catalyst (denoted as P 2 Z 3 -900, prepared in a mass ratio of m POP : m ZIF = 2 : 3) features hierarchical pore structure which could significantly enhance the mass transfer efficiency and promotes the exposure of active sites, leading to high ORR and OER activity in alkaline conditions, simultaneously. For example, P 2 Z 3 -900 presents a half-wave potential (E 1/2) of 0.81 V (vs RHE) with a diffusion-limited current density of 5.56 mA cm−2, comparable to commercial Pt/C (0.83 V and 5.60 mA cm−2), but much better than other prepared control samples. The Eonset of OER at 10 mA cm−2 reaches 1.60 V with a small Tafel slope of 57 mV dec−1. More importantly, the current synthetic method offers a rational strategy to structure-, morphology-, and element composition-controlled porous carbons, thereby finely regulating the property for efficient catalysis. A core-shell-structured POP@MOF composite was developed via solid-phase synthesis method. Upon carbonization, these special composites, with controllable morphology similar to ZIF-67 and adjustable Fe/Co molar ratio, can be further converted into N-doped porous carbons embedded with highly dispersed FeCo alloy and Fe/Co–N active sites. The obtained catalyst present prominent electrocatalytic performance for both ORR and OER in alkaline conditions. Image 1 [ABSTRACT FROM AUTHOR]

As a simple but effective approach to engineer the simultaneous geometric structure and composition diversity into one nano-material, hybrids have geared great research attention, recently. Here, a N-decorated sheet-on-rod heterostructure with hierarchical porosity, as well as homogeneously dispersed Co 5.47 N, Co 0.7 Fe 0.3 , and Fe/Co-Nx species on the phase interface, was developed via pyrolysis of a CMP-on-MOF bimetal hybrid, to achieve the bifunctional oxygen electrocatalytic activity. Conjugated microporous polymers (CMPs) are an emerging class of multifunctional materials combining the features of conventional conjugated polymers and porous materials, simultaneously. CMP-on-MOF was prepared via the assembly of Co-phthalocyanine-CMP (Co-CMP) on the surface of Fe-MIL-88B (Fe-MOF) through a solid-phase synthesis method. The optimized catalyst (PM-900), namely the product of hybrid pyrolysis, is obtained by finely regulating the composition of hybrid (m CMP to m MOF of 1:1) and pyrolysis temperature (900 °C) on the hybrid, simultaneously. The abundant Co 5.47 N, Co 0.7 Fe 0.3 , and atomically dispersed Fe/Co-Nx species are highly catalytically active, and the hierarchical porous structure provides easily accessible pathway for active sites, and the sheet-on-rod structure ensures a high electrical conductivity which is conducive for the catalysis. As a result, the optimum electrocatalyst, denoted as PM-900, presents a superb bifunctional electrocatalytic activity for both the oxygen reduction (ORR) and oxygen evolution reaction (OER) under alkaline conditions. Additionally, a home-made Zn–air battery (ZAB) comprising PM-900 catalyst presents prominent charge-discharge property even outperforms the mixture of Pt/C (20 wt%) and IrO 2. The hybrid strategy paves a new avenue for the rational design and synthesis of advanced bifunctional catalysts with intricate and unprecedented porous superstructures for reversible energy storage and conversion applications. N-decorated sheet-on-rod heterostructure with hierarchical porosity, as well as homogeneously dispersed Co 5.47 N, Co 0.7 Fe 0.3 , and Fe/Co-Nx species on the phase interface, was developed via pyrolysis of a CMP-on-MOF bimetal hybrid, to achieve the bifunctional oxygen electrocatalytic activity. [Display omitted] • CMP-on-MOF hybrid was employed as precursor for the preparation of bifunctional O 2 catalyst. • CMP-on-MOF bimetal was synthesized in the solid phase synthesis method. • Pyrolysis on hybrid yield sheet-on-rod heterostructure with hierarchical porosity. • PM-900 shows uniformly dispersed Co 5.47 N, Co 0.7 Fe 0.3 and Fe/CoNx on phase interface. • Zn-air battery comprising PM-900 presents prominent charge-discharge property. [ABSTRACT FROM AUTHOR]