fig2

Figure 2. Schematic illustration of TAC interface structures in carbon-based carriers: (A-D, H, K, L) Carbon and Nitrogen-coordinated atomic interface structures; (E) Carbon, Nitrogen, and hydroxyl (OH)-coordinated atomic interface structures; (F and G) Carbon, Nitrogen, and Sulfur-modified atomic interface structures; (I) Carbon and Phosphorus-doped atomic interface structures; (J) Carbon-coordinated atomic interface structures^{[23,34,40,43,46,69-73]}. TAC: Triatomic catalyst.