He Synthesis Of S,N-doped Porous Carbon Materials And Its Capacitive Deionization Performance

Since the 1950s,plastics have been used in large quantities,causing serious white pollution.Meanwhile,with the rapid development of global industries and the explosive growth of population,water problem has become prominent.If we can transform plastic waste into industrial material and use it in water treatment,it will be a far-reaching research topic.Based on dehalogenated reaction,we prepared three kinds of N,S-doped carbon materials,which were used as electrode materials in supercapacitor and electrosorption.This new method is probably put forward to solve the above problems:1.A facile strategy is developed to the fast fabrication of N,S-codoped carbon materials(NS-DCM)which exhibit a specific capacitance and high effciency toward electrosorption(capacitive deionization,CDI),with PVDC as carbon source,DMSO and DMF respectively as nitrogen and sulfare source.NS-DCM has a hierarchically porous structure with a specific surface area of 699 m2 g-1 and doping amounts of 3.0 atom%N and 2.4 atom%S.It shows excellent capacitances in acid,alkali and neutral electrolytes.In acidic electrolyte,it exhibits a very high specific capacitance of 427 F g-1 and also keeps?60%of capacitance at ultrahigh current density of 100.0 A g-1 Meanwhile,it exhibits a high effciency and long-term stability toward CDI with a desalination capacity of 32.3 mg g-1 in 40.0 mg L-1 NaCl.2.Based on the above study,an effective and environment-friendly way was proposed to synthesize doped porous carbon materials with excellent electrochemical performances,using waste plastics as carbon source.In this approach,different types of PVC plastic wastes such as table cloth/file bag/PVC tube/PVC film were respectively used as carbon source,and prepared into electrode materials(TC-C/DB-C/PW-C/PT-C).For instance,TC-C performed a capacitance of 430.1 F g-1 for acidic supercapacitor and a absorption capacity of 33.2 mg g-1 for CDI in NaC1 solution.3.Using thiourea as nitrogen and sulfare source,a new kind of N,S-codoped carbon materials(NS-C)was synthesized at room temperature for heavy metal ions adsorption.It has a hierarchically porous structure with a specific surface area of 1230 m2 g-1 and doping amount of 4.55 atom%N and 13.30 atom%S.The material exhibits very good absorption property for different heavy metal ions.For instance,the adsorption capacity for Fe2+was up to 125.2 mg g-1,and after five cycles,the efficiency also keeps?90%.The adsorption capacity for Pb2+reached 105.8 mg g-1.By characterization and analysis of composition and structure of the above three S,N-codoped carbon materials,it was found that their excellent capacitances and electrosorption performances were closev relatedto large specific surface areas,hierarchically porous structures,high doping amounts of heteroatoms,and good conductive properties.In addition,the synthesis process of high-performance electrode materials using waste plastics has potential commercial value in environmental protection.