New shape-selectivity discovered on graphene-based materials in catching tobacco specific nitrosamines

Abstract

New shape-selectivity of graphene-based materials was discovered on this article. To explore the new selectivity, the structure and surface state of graphene and carbon nanotube were examined firstly, and their specific selectivity was verified and was compared with that of ZSM-5 zeolite in aqueous solutions of tobacco specific nitrosamines (TSNA) along with dyes. These two adsorbents trapped about 55% and 70% of 4-methylnitrosamino-1-3-pyridyl-1-butanone (NNK) but only 3% of N’-nitrosonornicotine (NNN) in solution, having an obvious selectivity for the former, due to its stronger interaction with graphene. NNK on graphene sheet obtained more electrons (0.015 e) and owned larger adsorption energy (15.63 kcal mol−1) than that of NNN (0.003 e, 9.19 kcal mol−1), according to theoretical calculation and FTIR results. More 95 or 136 mg g -1 acid red 88 than methyl orange was captured by graphene or carbon nanotube, demonstrating this special and abnormal selectivity again. With new selectivity, graphene showed a higher capacity (6.9%) and shorter adorption equilibrium time (5 min) for TSNA than the typical selecive sorbent ZSM-5 zeolite (1.7% and 20 min) in tobacco solution but kept the similar selctivity to NNK, paving a new way to control the carcinogens like TSNA in environment.