advantages of zinc-air batteries (ZABs), such as high energy density and theoretical capacity, low cost, high safety, and stability, endow them with huge application potential in the field of energy storage and conversion. [4,5] During the charging and discharging process of ZABs, oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) play a crucial role in determining the energy conversion efficiency. [6] Both of ORR and OER involve complex multiple electron transfer processes. [7] The inherently slow kinetics of ORR and OER leads to lofty overpotentials, resulting in low energy efficiency, and low power density of ZABs. [8] Noble metal-based electrocatalysts (such as Pt/C, RuO 2 , IrO 2 ) exhibit superior oxygen electrocatalytic activity, while the high cost and deficient stability hinder their industrial-scale application in the rechargeable ZABs. [9,10] Therefore, it is urgent to develop stable and efficient nonnoble metal-based ORR/OER bifunctional electrocatalysts to facilitate the development of ZABs. [11] In alkaline solution, the favorable four-electron ORR for ZABs follows: 1) O 2 (g)where * denotes the active site. [12] The second and fourth steps both involve the coupling process of activated Oxygen reduction reaction (ORR) is the key reaction on cathode of rechargeable zinc-air batteries (ZABs). However, the lack of protons in alkaline conditionslimits the rate of ORR. Herein, an activating water strategy is proposed to promote oxygen electrocatalytic activity by enhancing the proton production from water dissociation. FeP nanoparticles (NPs) are coupled on N-doped wood-derived catalytically active carbon (FeP-NWCC) to associate bifunctional active sites. In alkaline, FeP-NWCC possesses outstanding catalytic activities toward ORR (E 1/2 = 0.86 V) and Oxygen evolution reaction (OER) (overpotential is 310 mV at 10 mA cm −2 ). The liquid ZABs assembled by FeP-NWCC deliver superior peak power density (144 mW cm −2 ) and cycle stability (over 450 h). The quasi-solid-state ZABs based on FeP-NWCC also display excellent performances. Theoretical calculation illustrates that the superb bifunctional performance of FeP-NWCC results from the elevated dissociation efficiency of water via FeP NPs to assist the oxygen catalytic process. The strategy of activating water provides a new perspective for the design of ORR/OER bifunctional catalysts. This work is a model for the application of forest biomass.

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Here, we report kinetic studies using electron spin resonance spectroscopy on spin catalysis reactions caused by using graphene belts which were synthesized by a radical coupling method. The results show that σtype free radical species provide the dominant sites for catalytic activity through the spin-spin interaction, although there are some other influencing factors. The spin catalysis mechanism can be applied both in the oxygen reduction reaction (ORR) and in organic synthesis. The graphene belt spin catalyst shows excellent performance with a high ORR half-wave potential of 0.81 V and long-term stability with almost no loss of activity after 50 000 cycles in alkaline media. It also shows excellent performance in a benzylamine coupling with molecular oxygen to generate the corresponding imine at an average conversion of � 97.7 % and an average yield of � 97.9 %. This work opens up a new research direction for understanding aerobic processes in the field of spin catalysis.

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