N-doping copolymer derived hierarchical micro/mesoporous carbon:Pore regulation of melamine and fabulous adsorption performances

Abstract

A facile two-step method including hydrothermal reaction and activation at high temperature was designed to prepare nitrogen doped copolymer derived carbon materials with melamine(M) as nitrogen source and resorcinol(R)-furfural(F) resin as carbon precursor. The melamine not only introduces nitrogen in the copolymer-based carbon materials but also tunes the pore structure of the obtained samples. The as-prepared nitrogen-rich carbon materials (RMFC-3.6) possess an ultra-high specific surface area of 2572.33 m2 g−1 with ideal channel structure and nitrogen content up to 1.40 wt.%. RMFC-3.6 exhibits excellent adsorption capacity and fast adsorption rate for most dyes. Using Congo red (CR), Rhodamine B (RhB) and Malachite green (MG) as waste water pollutant models, the maximum adsorption capacities of CR, Rh B and MG reached 3207.61, 2947.42 and 5769.23 mg g−1, respectively, much higher than the reported values. Moreover, the adsorption process of RMFC-3.6 has a good correlation with Langmuir isotherms and coincides with pseudo-second-order kinetic models. Significantly, the adsorption capacity retention of RMFC-3.6 for CR after four cycles maintains 93.17%, indicating excellent cycling stability.