Chemical Structure and Distribution in Nickel–Nitrogen–Carbon Catalysts for CO₂ Electroreduction Identified by Scanning Transmission X-ray Microscopy

/C sites were notably demonstrated by spectroscopy to possess a variety of chemical structures with a spectroscopic signature that most closely resembles nickel(II) tetraphenylporphyrin molecules. The quantification and spatial distribution mapping of atomically dispersed Ni active sites achieved by STXM address a target that was elusive to the scientific community despite its importance in guiding advanced material designs.