▎ 摘　　要

NOVELTY - The nanosheet has a carbon shell provided with a hollow inner cavity that is wrapped with a reducing oxidation graphene. The carbon shell is provided with porous amorphous carbon that is doped with a nitrogen, where atom doping amount of the nitrogen is about 2. 5 mol percent to 4 mol percent. The carbon shell is distributed with a medium hole that is vertically connected with an inner and an outer wall, where aperture of the medium hole is about 6-9 nm. USE - Nitrogen-doped hollow mesoporous carbon nano-sheet for use in a negative electrode of a potassium ion battery (claimed) i.e. lithium ion battery. ADVANTAGE - The nanosheet provides a considerable mass ratio capacity and exhibits excellent rate performance and cycle stability, and realizes ideal carbon-based current collector material of potassium ion negative electrode so as to construct a potassium ion battery with safety, high quality specific capacity and long cycle life. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a method for preparing a nitrogen-doped hollow mesoporous carbon nanosheet. DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of a nitrogen-doped hollow mesoporous carbon nano-sheet for use in a negative electrode of a potassium ion battery i.e. lithium ion battery. (Drawing includes non-English language text).