Prepatterned Cyanuric Acid Template for Reaching the Theoretical Upper Limit of Nitrogen-Doped Graphene for Nonradical Oxidation

Peroxymonosulfate (PMS)-based advanced nonradical oxidation is a cutting-edge technology in environment remediation. However, the low graphitic N content greatly limits the nonradical catalytic performance of N-doped graphene. Herein, almost theoretical upper-limited N-doped porous graphene (TUNPG) was obtained via pyrolysis of melamine-cyanurate and 2-benzimidazolethiol at a graphitic N formation temperature of 1000 degree celsius. During the pyrolysis, cyanuric acid decomposed into numerous N-containing gases, which exfoliated melamine-polymerized graphitic carbon nitride intermediates into nanosheets. At 1000 degree celsius, the nanosheets were carbonized into TUNPG with an N content of 10.10 atom %, close to the theoretical upper limit of 12.5 atom %. The obtained TUNPG also possessed a high graphitic N proportion and a large Brunauer-Emmett-Teller surface area, enabling a catalytic performance 6.6 times higher than that of ultrahigh N-doped carbon for degrading organics. Pathways for PMS activation at the graphitic N site were theoretically explored. This work presents a strategy for the fabrication of carbonaceous materials and offers insights into 1O2 production at the atomic scale, providing new guidance for developing N-doped graphene for various practical applications.