Journal Article Zn-air batteries water splitting CO electroreduction Cu3N W2N/WC heterostructures ambient synthesis ampere‐level CO2 electroreduction atom‐scale cascade catalysis bulk metals density functional theory electrocatalysis heterostructures high concentration products streams lattice dislocations multi-carbon products multi‐active site collaboration self-supporting film single atom alloys single-atom catalysts solid diffusion surface dangling bonds