Stabilizing Phosphorene Nanosheets by Covalent Oxygen-Bridged Yttrium Oxide Nanosheet Bonding for Promoting Interfacial Sodium Storage

As one of the emerging two-dimensional (2D) graphene-analogous nanomaterials, black phosphorus nanosheets (BPNs) have been considered as one of the promising electrode candidates in electrochemical ion storage applications. However, the presence of the lone-pair electrons in phosphorus atoms endows them much sensitivity to external conditions, leading to an undesired structural degradation. Herein, a covalently oxygen-bridged yttrium bonding is proposed within the 2D/2D black phosphorus/yttrium oxide (BPN/YON) heterostructures by using 2D yttrium oxide nanosheets as the modifier, in which the Y-O-P bridge is formed between oxygen in yttrium layers and phosphorus in phosphorene layers. It is verified that this rational design is favorable for stabilizing phosphorene while promoting interfacial adsorption toward sodium ions for sodium-ion batteries. This work opens an avenue for the potential utilization of the emerging phosphorene in energy storage applications and also offers us some innovative concepts on the synchronous consideration for both structural stabilization and performance enhancement via surface or edge passivation on 2D nanosheets.