“…Arranging the nanomaterials into 3D architectures has also been investigated. [71,72] In addition, electrodes based on core-shell structures [73,74], 3D hierarchical porous architectures [75,76], and sandwich structures [77,78], associated with good mechanical stability, large surface area, and numerous active sites receive wide exploitation in supercapacitors and batteries. [79][80][81] However, most of these new 3D structural tin dioxide materials are not suitable for flexible devices either because they have poor electrical conductivity, or because they require expensive methods for preparation.…”