Mechanism of nicotine degradation and adsorption by nano-TiO2 engineered reduced graphene oxide composite in light variant condition
Nicotine (C10H14N2), a hygroscopic molecule has been the focus of intensive research for the rising number of detrimental impacts on human health, associated with the neuroactive alkaloid in tobacco. This study reports exclusive nicotine degradation and adsorption activity from its aqueous solution through the anatase phased nano-TiO2 (20±5nm) decorated reduced graphene oxide (rGO-TiO2) composite under ultra-violet (UV) and visible light irradiation respectively. About 80% of nicotine decomposition is found by 2mg rGO-TiO2 under UV light, and 59% nicotine adsorption at the surface of rGO-TiO2 is detected in visible light condition. The kinetic study based on free radicals generation (O2⦁-, ⦁OH, 1O2) confirms that rGO-TiO2 nanosystem has a substantial rate of ROSs formation ability. The attachment of nano TiO2 makes rGO defective in sp3-hybridized carbon, altering electronic energy states of rGO-TiO2 leads to superior nicotine adsorption via π–π and cation-π interactions. Nicotine degradation is perceived to follow a pseudo-first-order kinetic law while adsorption due to chemisorption of the disordered rGO-TiO2 surface can be expressed via the Langmuir isotherm model. The rGO-TiO2 nanohybrid is highly suggested to be beneficial on the industrial basis for nullifying the nicotine prompted carcinogenic effects in the aquatic system.