Maricite α-phase sodium cobalt phosphate (α-NaCoPO₄) (so called NCP) was fabricated by easily scalable and energy efficient method such as solution combustion synthesis. The obtained material was further ball-milled with carbon (NCP/C) to get nano-sized resultant particles. The orthorhombic crystal structure was confirmed by powder X-ray diffraction and purity of the material evidenced by X-ray photoelectron spectroscopy (XPS). The surface morphology and particle size of the materials were studied by scanning electron and transmission electron microscopic analyses. In cyclic voltammetric analysis, the cathode made up of NCP/C material showed a significant redox activity at 2.33 and 4.3 V. The NCP/C material exhibited a reversible intercalation with a discharge capacity of 36 mAh g⁻¹ at 0.1 C and 50% capacity retention after 100 cycles in Na half-cell. To the best of our knowledge, the maricite α-NaCoPO₄ cathode has been taken part in the charge/discharge process with the active sodium ions.

Graphical abstract

马来石α-相磷酸钴钠（α- NaCoPO ₄）（所谓的NCP）是通过易于扩展且节能的方法（例如溶液燃烧合成法）制造的。将获得的材料进一步用碳（NCP / C）进行球磨，以获得纳米级的所得颗粒。通过粉末X射线衍射和材料的纯度通过X射线光电子能谱（XPS）证实了正交晶的晶体结构。通过扫描电子显微镜和透射电子显微镜分析研究了材料的表面形态和粒度。在循环伏安分析中，由NCP / C材料制成的阴极在2.33和4.3 V电压下显示出显着的氧化还原活性。NCP/ C材料显示出可逆的嵌入，放电容量为36 mAh g在Na半电池中经过100次循环后，在0.1 C时^-1和50％的容量保持率。据我们所知，马来石 α- NaCoPO ₄阴极已与活性钠离子一起参与了充电/放电过程。

图形概要