Study On Preparation Of Nanospheres Carbon Materials And Its Adsorption Properties

Because of the water pollution and greenhouse effect problems,it is imperative to develope advanced adsorbents and energy storage materials to deal with.For its outstanding properties such as larger specific surface area and pore volume,uniform pore structure,designed morphology of surface chemical properties and other characteristics,the spherical carbon materials have been used in many modern scientific domain,including catalysis,supercapacitor,energy storage,adsorption and separation in many modern science.In this paper,a study has been made on the synthetic method,in which the spherical carbon materials can be prepared with different properties and appled into removal of water pollutant.The main results are shown as follows:1)The mesoporous polymer nanospheres with diameter of about 110 nm were synthesized by using phenol and formaldehyde as carbon sources,triblock copolymer F127 as template.After introducing Fe₃O₄ nanoparticles and carbonization processes,the iron-containing magnetic mesoporous carbon nanospheres?Fe-MCNs?with different iron content were then obtained.The adsorption properties of Cr?VI?in aqueous solution proved that the Fe-MCNs combined with Fe₃O₄ nanoparticles and mesoporous carbon nanospheres?MCNs?shown a cooperative adsorption performance for Cr?VI?.And with the increase in the amount of iron doped,the adsorption amount increased.At the same time,Fe-MCNs can be separated and recovered from the aqueous solution conveniently and rapidly by the external magnetic field.The isotherm equilibrium model and adsorption kinetics model were also used to examine the adsorption process,which might offer a possibility of Fe-MCNs as industrial adsorbent.2)Hollow carbon nanospheres?HCNs?were developed by self-catalyzed method firstly.The HCNs were synthesized by using RF resin as a carbon precursor and the amino modified SiO₂ nanospheres?NH₂-SiO₂?as hard templates and and catalyst.There was no need to apply any surfactant and aqueous ammonia in the self-catalyzed process.As a basic group,the amino provided slight alkaline conditions which could catalyze the polymerization of resorcinol-formaldehyde?RF?resin.Additionally,the amino group covering the outer surface of SiO₂ turn to be slight positively charged in the solution,which allowed deposition of negatively charged RF on the surface of NH₂-SiO₂ and prepared developed the NH₂-SiO₂@RF core-shell structure.After carbonization and removal of the SiO₂ templates,the obtained HCNs completely copied the morphology of SiO₂,exhibiting uniform and monodispersed spherical structures with uniform diameter and surface area of 777 m2 g-1.The sample exhibited a performance for CO₂ capture after activation with KOH.In addition,the self catalyzed method was also successfully extended to the use of other carbon sources?such as: m-aminophenol,melamine?to prepare a uniform size of HCNs.3)Hollow carbon nanospheres?HCNs?were prepared by employing SiO₂ nanospheres as hard template,HMF as carbon precursor under hydrothermal conditions.The HCNs showed large cavity,thin shell structure and high surface area,as well as exhibited a promising prospect for CO₂ capture.Repeated CO₂ adsorption-desorption experiments revealed the good recyclability of HCNs which extended the use of biomass derivatives and provides a useful enlightenment for the preparation of HCNs.