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Abstract The Sodium-ion-battery, using the layered oxide material as cathodes coupled with carbon anodes, has been proposed for utilization in practice long time ago. However, the prevailing layered oxides is still hindered by serious phase transition and volume strain upon sodium release. Herein, we show a novel copper doped layered P_1 manganese-based oxide material (NCM) with unique bulk and nanoscale Na-free surface structures as a sodium host to overcome the above limitation. Our research disclosed this P_1 NCM material has a wide phase-transition-free zone between 2 V and 4.5 V with a tiny lattice volume change upon cycling. Besides, it delivers an excellent chemical stability during humid air exposure. In contrast to most environmentally sensitive layered materials, after aging for 60 days in humid air, P_1 NCM still exhibits the superior cycling performance (95.8% capacity retention after 1000 cycles) and excellent rate capability as well as an outstanding sodium storage performance in full cells. Graphical abstract A novel P_1 structure based cooper doped manganese oxide was successfully synthesized which has a nanoscale Na-free surface and a solid solution phase transition behavior upon cycling between 2 V and 4.5 V and exhibits outstanding air stability and ultra-long cycle life of sodium-storage properties. fx1 Highlights • The P_1-NCM are composed by the unique P_1-typed bulk and Na-free surface. • The P_1-NCM demonstrates an excellent chemical stability in humid air. • The P_1-NCM exists an extremely wide phase-transition-free zone from 2 V to 4.5 V. • The P_1-NCM after aging shows the superior cycle life. [ABSTRACT FROM AUTHOR]

The design of efficient and sustainable platinum-based catalysts is the key to developing direct alcohol fuel cells. Here, we designed highly open, one-dimensional Pt–Ni architectures with controllable wall thickness by selectively etching Pt–Ni nanowires. Pt atoms of both the inner and outer Pt–Ni architectures can participate in the electrochemical process, dramatically increasing the number of active sites and resulting in excellent alcohol electrooxidation performance. The obtained Pt1Ni5-M architecture with an ultrathin wall of 1.18 nm and a more open structure shows the best performance. The methanol oxidation reaction and ethanol oxidation reaction mass activities of Pt 1 Ni 5 -M are 7.4 (1.93 A/mg Pt) and 4.6 (0.96 A/mg Pt) times higher than that of Pt/C, respectively. After 3600s chronoamperometry tests, these Pt–Ni architectures also show improved durability with limited decay. This simple strategy inspires us to create more suitable catalysts with open structures for direct alcohol fuel cells. One-dimensional porous PtNi architectures with controllable wall thickness, particularly Pt 1 Ni 5 -M with subnanometer walls, significantly boosted platinum atom utilization, resulting in excellent alcohol oxidation performance. [Display omitted] • A novel porous one-dimensional PtNi architecture with controllable wall thickness and high openness was designed. • The wall thickness of Pt 1 Ni 5 -M can be controlled in a sub-nanometer range. • PtNi architectures greatly improve the utilization rate of Pt atoms and increase alcohol electrooxidation activity. • The alcohol electrooxidation activity trends of Pt 1 Ni x -M catalysts were negatively correlated with the wall thickness. [ABSTRACT FROM AUTHOR]