Polymer gel electrolytes have been actively employed in exploiting solid-state supercapacitors. However, the access to tiny pores of electrode materials is hindered by the sticky nature and sluggish ion transport of polymers. Consequently, supercapacitors usually present much lower capacitance in gel electrolytes than in liquid electrolytes. Here, we develop a molten-salt-directed mesopore engineering to design carbon nanotubes that are highly accessible to gel electrolytes. The rich mesopores, 12–15 nm in diameter and cross-linked, drastically facilitate the infilling of gel electrolytes into carbon nanotubes, leading to robust capacitive performance. Such mesoporous carbon nanotubes exhibit a high capacitance of 195.2 F g⁻¹ in polyvinyl alcohol electrolyte and an ion diffusion coefficient of 2.8 × 10⁻⁷ cm² s⁻¹, close to that in liquid electrolyte. Additionally, solid-state supercapacitors based on mesoporous carbon nanotubes exhibit a short relaxation time of 39 ms and a capacity retention of 93% over 10000 cycles, thus demonstrating their great potential in practical applications.

聚合物凝胶电解质已被积极用于开发固态超级电容器。然而，聚合物的粘性和缓慢的离子传输阻碍了电极材料微小孔的进入。因此，超级电容器在凝胶电解质中的电容通常比在液体电解质中低得多。在这里，我们开发了一种以熔盐为导向的中孔工程，以设计易于凝胶电解质使用的碳纳米管。直径为 12-15 nm 且交联的丰富中孔极大地促进了凝胶电解质填充到碳纳米管中，从而实现了强大的电容性能。这种介孔碳纳米管在聚乙烯醇电解质中表现出 195.2 F g ^{-1的高电容和 2.8 × 10 的离子扩散系数-7}  cm ²  s ^-1，接近液体电解质。此外，基于介孔碳纳米管的固态超级电容器表现出 39 ms 的短弛豫时间和 10000 次循环后 93% 的容量保持率，从而显示出其在实际应用中的巨大潜力。