Triton X-100-directed synthesis of carbon nitride and nitrogen-doped carbon for ethylene dichloride dehydrochlorination.

Nitrogen-doped carbons (NC) and carbon nitride (C 3 N 4) belong to the two fundamental pillars of functionalized carbon materials that have broad applications in different fields. The synthesis of NC and C 3 N 4 often starts from different precursors, and a general approach that can offer both architectures is still highly sought. Herein, a facile Triton X-100-assisted copolymerization-carbonization strategy is reported to fulfill this task. By moderating the weight ratios of Triton X-100 and several conventional precursors of C 3 N 4 (e.g., dicyandiamide, urea, and cyanamide), a series of both types of N-functionalized carbons with controllable N dopants is successfully afforded. The yielded solids transform from graphitic C 3 N 4 with low surface areas to porous NC when the weight ratio reaches the critical values. This phenomenon might be attributed to the intensified copolymerization between the intermediates of both starting precursors during the carbonization, resulting in increased oxygen content and decreased N:C ratio in the products. Both the bulk and activated carbon-supported materials are then designed and used as metal-free catalysts in the dehydrochlorination of ethylene dichloride, a key reaction in polyvinyl chloride manufacture. It is found that NC is significantly more active than C 3 N 4 , but the corresponding supported catalysts exhibit an opposing trend. The structure-activity correlations suggest both the number of different N defects and the surface areas might play key roles in determining the dehydrochlorination chemistry. Tailor synthesis of C 3 N 4 and N-doped carbons with controllable N defects was enabled by a newly developed approach through co-pyrolysis of Triton X-100 and conventional C 3 N 4 precursors. [Display omitted] [ABSTRACT FROM AUTHOR]