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The N -doped carbon encapsulated Zn 2 VO 4 polyhedron composite (ZVO/NC) with enhanced pseudocapacitive behavior for Li+/Na+/K+ storages are designed and fabricated by a self-assembly strategy and followed by the calcination procedure. [Display omitted] • The Zn 2 VO 4 nanocrystals embedded in N -doped carbon was derived from V/Zn-MOFs. • The Zn 2 VO 4 phase was used as anode of SIBs/PIBs for the first time. • Excellent stability and high capacity were realized for SIBs (145 mAh g−1 at 7000th cycles). In this work, we fabricated vanadium/zinc metal–organic frameworks (V/Zn-MOFs) derived from self-assembled metal organic frameworks, to further disperse ultrasmall Zn 2 VO 4 nanoparticles and encapsulate them in a nitrogen-doped nanocarbon network (ZVO/NC) under in situ pyrolysis. When employed as an anode for lithium-ion batteries, ZVO/NC delivers a high reversible capacity (807 mAh g−1 at 0.5 A g−1) and excellent rate performance (372 mAh g−1 at 8.0 A g−1). Meanwhile, when used in sodium-ion batteries, it exhibits long-term cycling stability (7000 cycles with 145 mAh g−1 at 2.0 A g−1). Additionally, when employed in potassium-ion batteries, it also shows outstanding electrochemical performance with reversible capacities of 264 mAh g−1 at 0.1 A g−1 and 140 mAh g−1 at 0.5 A g−1 for 1000 cycles. The mechanism by which the pseudocapacitive behaviour of ZVO/NC enhances battery performance under a suitable electrolyte was probed, which offers useful enlightenment for the potential development of anodes of alkali-ion batteries. The performance of Zn 2 VO 4 as an anode for SIBs/PIBs was investigated for the first time. This work provides a new horizon in the design ZVO/NC as a promising anode material owing to the intrinsically synergic effects of mixed metal species and the multiple valence states of V. [ABSTRACT FROM AUTHOR]

[Display omitted] • P-Pd nanoparticles were facilely prepared based on polyphosphide chemistry. • The soluble phosphorus anion was used as both P source and reducing agent. • P significantly improves catalytic activity through size and electronic effects. • The P-Pd exhibited surprising anti-CO poisoning ability. • DFT calculations showed the indirect pathway was inhabited by P-doping. In this work, we reported a novel polyphosphide strategy for the synthesis of phosphorus doped Pd (P-Pd) using red phosphorus as the starting material at quasi-ambient conditions. Polyphophide anions, as the key reaction intermediates, served as the reducing agent and phosphorus source to modulate the surface electronic structure of Pd. The P-Pd obtained exhibited topmost CO tolerance and electrocatalytic activity to formic acid oxidation among the state-of-arts reports. The mass activity and turnover frequency of P-Pd reached 4413 mA mg−1 Pd and 16.04 s−1 at 0.8 V, which were 23.7 and 6.4 times that of commercial Pd/C respectively. After 1000 repeated cycles, 82% initial activity was reserved. Combined with the electrochemical analysis and the density functional theory calculation, the boosted electrochemical performances can be attributed to the size and electronic effects induced by the P doping, which increase the surface actives sites, inhibit the adsorption of CO and change the reaction pathway to favorable CO 2 route. A full cell was also assembled to demonstrate the practical potential of the P-Pd, which showed a maximum power density of 21.56 mW cm−2. This polyphophide-based reaction route provides a new strategy for the preparation of efficient and durable phosphorus doped alloys for electrocatalysis. [ABSTRACT FROM AUTHOR]