context: C-based materials such as spheres, fibers, and cages have been reported to adsorb polysulfides. Their ability to trap LiPSs in cathodes suppresses the shuttle effect, and improves the cycling of Li–S batteries. To compare the LiPS adsorption on hollow Co5.47Nx–C and C spheres, visual adsorption tests were conducted using Li2S6 as the LiPS; the results are presented in Fig. 4a. The initially yellow Li2S6 solution containing hollow Co5.47Nx–C spheres became colorless after 8 h. In contrast, the equivalent test with C spheres showed slight fading of the yellow solution. This showed that the Co5.47Nx–C spheres adsorbed the LiPS more readily than the C spheres. This was attributed to both physical and chemical adsorption because of the Co5.47Nx nanoparticles and mesoporous hollow layer of the Co5.47Nx–C spheres.