Back Cover Image, Volume 5, Number 8, August 2023

Back cover image: Carbon-based composite electrocatalysts doped with transition metals and heteroatoms are expected to replace noble metal-based catalysts as high-efficiency catalysts for OER and ORR. In the article number 10.1002/cey2.317, Zhang et al. prepare an ultralong N,S co-doped carbon nano-hollow-sphere chain with encapsulated Co nanoparticles, analyze its growth mechanism and catalytic activity for ORR/OER, and provide a novel approach for the rational synthesis of efficient multifunctional carbon-based catalysts for energy storage.