Journal Article Coloring Agents EC 1.11.1.- EC 1.11.1.7 H2O2 treatment Peroxidase Peroxidases catalytic tumor therapy cation distribution crystallization edge-generation fluid dynamics hydrogen peroxide production in situ microscopy inner‐sphere electron transfer pathway mathematical modeling meniscus multi-metal oxides multi‐level tuning strategy octahedron‐like cobalt structure oxygen reduction electrocatalysis peroxidase-like activity single-atom nanozymes spinel oxides structure-activity relationship uniform-sized nanoparticles