The CsPbBr3@NH4Br nanocomposites were successfully synthesized through ion exchange. The nanocomposites possessed a special core@shell structure and exhibited a high absolute PLQY, long lifetime, good water resistance and excellent thermal stability.

Zinc–air batteries (ZABs) are promising as energy storage devices owing to their high energy density and the safety of electrolytes. Construction of abundant triple‐phase boundary (TPB) effectively facilitates cathode reactions occurring at TPB. Herein, a wood‐derived integral air electrode containing Co/CoO nanoparticles and nitrogen‐doped carbonized wood (Co/CoO@NWC) is constructed with a dual catalytic function. The potential gap between oxygen reduction and evolution is shortened to 0.77 V. Liquid ZABs using Co/CoO@NWC as cathode exhibit high discharge specific capacity (800 mAh gZn−1), low charge–discharge gap (0.84 V), and long‐term cycling stability (270 h). Co/CoO@NWC also shows distinguished catalytic activity and stability in all‐solid‐state ZABs. The inherent layered porous and pipe structures of wood are well maintained in catalytically active carbon. The different hydrophilicity of carbonized wood and Co/CoO endow abundant TPBs for battery reaction. The Co/CoO located on TPB provides main active sites for oxygen reactions. The inherent pipe structures of wood carbon and the interaction between Co/CoO and NWC effectively prevent nanoparticles from aggregation. The design and preparation of this monolithic electrocatalyst contribute to the broad‐scale application of ZABs and promote the development of next‐generation biomass‐based storage devices.

Electrochemical reduction of oxygen plays a critical role in emerging electrochemical energy technologies. Multiple electron transfer processes, involving adsorption and activation of O2 and generation of protons from water molecules, cause the sluggish kinetics of the oxygen reduction reaction (ORR). Herein, a double‐active‐site catalyst of Fe3C nanoparticles coupled to paulownia wood‐derived N‐doped carbon (Fe3C@NPW) is fabricated via an active‐site‐uniting strategy. One site on Fe3C nanoparticles contributes to activating water molecules, while another site on N‐doped carbon is responsible for activating oxygen molecules. Benefiting from the synergistic effect of double active sites, Fe3C@NPW delivers a remarkable catalytic activity for ORR with a half‐wave potential of 0.87 V (vs. RHE) in alkaline electrolyte, outperforming commercial Pt/C catalyst. Moreover, zinc–air batteries (ZABs) assembled with Fe3C@NPW as a catalyst on cathode achieve a large specific capacity of 804.4 mA h gZn−1 and a long‐term stability of 780 cycles. The model solid‐state ZABs also display satisfactory performances with an open‐circuit voltage of 1.39 V and a high peak power density of 78 mW cm−2. These outstanding performances reach the level of first‐rank among the non‐noble metal electrode materials. This work offers a promising approach to creating double‐active‐site catalysts by the active‐site‐uniting strategy for energy conversion fields.

No abstract