“…In particular, ultralight materials based on nanocarbons, such as carbon nanotubes (CNTs) and graphene, have attracted attention in many applications such as sensors, electrodes, insulators, and adsorbents [ 9 , 10 , 11 , 12 , 13 ]. These ultralight materials are generally fabricated in the density range of less than 10 mg/cm 3 , and much research has been conducted on the correlation between their structure and mechanical properties [ 13 , 14 , 15 , 16 , 17 , 18 , 19 ]. In recent years, the weight of these ultralight materials has been further reduced, and materials of density approaching the air density (1.29 mg/cm 3 ) are being developed [ 1 , 20 ].…”