“…Three peaks of 284.7 285.3, and 290.3 eV in the C 1s spectrum were defined as CC (49.0%), CN (38.9%), and O–CO (12.1%), respectively (Figure S1g). As presented in Figure S1h, the N 1s spectrum was fitted into three characteristic peaks of pyridinic- N (398.6 eV, 40.8%), pyrrolic- N (400.3 eV, 34.1%), and graphitic- N (401.2 eV, 25.1%), respectively, demonstrating the presence of graphitic N. In addition, the O 1s spectrum had been fitted into four characteristic peaks of CO (532.0 eV, 37.6%), C–O–C (532.7 eV, 27.7%), C–OH (533.6 eV, 23.7%), and O 2 /C (536.9 eV, 11.0%), illustrating the presence of surface oxygenic functional groups (Figure S1i). The morphologies of Co-NCNRs were also investigated by SEM and TEM.…”