Bismuth oxychloride ultrathin nanoplates as an anode material for sodium-ion batteries

Two-dimensional bismuth oxychloride (BiOCl) ultrathin nanoplates with a thickness of 10–20 nm are synthesized by a simple hydrothermal method. The as-prepared product is explored as an anode material for sodium-ion batteries for the first time. It shows BiOCl ultrathin nanoplates with two very suitable discharge voltage plateaus (0.6 V and 0.4 V) for sodium ion batteries. Furthermore, a two-step sodiation mechanism including an intercalation reaction and a conversion reaction is proposed. This work reveals a novel electrode material for sodium-ion batteries beyond conventional materials (such as transition metal oxides, carbon materials and alloys) and encourages more researchers to further investigate BiOCl.