ZnCl2 as a "Nitrogen Bank" to Inhibit Nitrogen Loss during the Thermal Conversion of Nitrogen-Containing Carbon Precursors to Nitrogen-Doped Carbon

A universal synthesis strategy for inhibiting the nitrogen loss during the thermal conversion of N-containing carbon precursors to nitrogen-doped carbon is developed. ZnCl2, as a sacrificial additive in the pyrolysis, acts like a "nitrogen bank" ("N-bank") to accommodate the N-containing intermediates from the decomposed precursors and redopes the nitrogen back into the final carbon materials. The nitrogen-doped carbon synthesized by this N-bank synthesis strategy has a significantly elevated nitrogen content and shows an excellent catalytic performance toward the oxygen reduction reaction (E-1/2 = 0.89 V-RHE).