Carbon nanosheets have been considered as promising candidates for supercapacitors. However, it is still challenging to construct carbon nanosheets incorporating nanoscale thickness and controllable hierarchically porous structure. Herein, a type of novel carbon nanosheets with well-developed hierarchical micro-/meso-/macropores are synthesized by combining bubbling and templating methods, in which an organic-metal salt (ferrous gluconate) with low melting point is used as carbon source. The prepared carbon nanosheets have exceptional structural controllability, that is, the sheet thickness can be well tailored from 142 to 53 nm, and the embedded pores are adjustable in the range of 20 nm–168 nm. Meanwhile, owing to robust carbon skeleton to tolerate the KOH etching, the surface area of carbon nanosheets can be raised to 3230 m² g⁻¹ after an activation process. Based on these unique structural merits, the carbon nanosheets exhibit attractive supercapacitive performance. The specific capacitance can reach 235 F g⁻¹ at 0.1 A g⁻¹, and even at a very large current density of 50 A g⁻¹, a high capacitance of 168 F g⁻¹ is still retained, indicating good retention of 71%.

碳纳米片已经被认为是超级电容器的有希望的候选者。然而，构建具有纳米级厚度和可控的分级多孔结构的碳纳米片仍然是挑战。在此，通过结合起泡和模板化方法，合成了具有发达的分级的微/中/大孔的新型碳纳米片，其中低熔点的有机金属盐（葡萄糖酸亚铁）用作碳源。制备的碳纳米片具有出色的结构可控性，也就是说，片的厚度可在142至53 nm之间适当调整，并且嵌入的孔可在20 nm至168 nm的范围内调节。同时，由于坚固的碳骨架可以耐受KOH蚀刻，碳纳米片的表面积可以提高到3230 m激活过程后为²  g ^-1。基于这些独特的结构优点，碳纳米片表现出有吸引力的超电容性能。 在0.1 A g ^-1时，比电容可以达到235 F g ^-1，即使在50 A g ^-1的非常大的电流密度下，仍可以保持168 F g ^-1的高电容，表明良好的保持71 ％。