For the first time, we successfully synthesize a self-supported Na_0.7CoO₂ nanosheet arrays via the facile “sodiation and post-calcination” method. Different from the traditional high temperature solid-state technique, this facile strategy can easily maintain the novel construction of the precursor. A mass loading as high as 8 mg cm⁻² is achieved for the Na_0.7CoO₂ electrode with an initial capacity of 145.2 mAh g⁻¹ at 1 C. Most importantly, the corresponding areal capacity for the Na_0.7CoO₂ electrode is calculated to be 1.16 mAh cm⁻². This superb areal capacity is higher than that of the previously reported cathode materials. This special “sodiation and post-calcination” protocol mentioned in this article guarantees the high mass loading of Na_0.7CoO₂ on Ni foam, providing a straightforward direction for engineering high-areal-capacity cathode materials.

我们首次通过简便的“沉淀和后煅烧”方法成功合成了自支撑的Na _0.7 CoO ₂纳米片阵列。与传统的高温固态技术不同，这种简便的策略可以轻松维护前驱体的新颖结构。Na _0.7 CoO ₂电极在1 C时的初始容量为145.2 mAh g ^-1，可实现高达8 mg cm ^-2的质量负载。最重要的是，计算出Na _0.7 CoO ₂电极的相应面积容量为1.16 mAh cm ^-2。这种极好的面积容量高于先前报道的阴极材料的容量。本文提到的这种特殊的“沉淀和后煅烧”方案可确保在泡沫镍上大量负载Na _0.7 CoO ₂，这为工程设计大面积容量的阴极材料提供了直接的指导。