Effect of KOH Dosage on the Physicochemical Properties and Supercapacitor Performance of Coal Gasification Fine Ash Derived Active Carbon
Coal gasification fine ash(CGFA)is the product of incomplete coal gasification,showing the characteristics of high emissions and difficulties of treatment,which leads to the issues of the environmental pollution and resource waste.In order to further promote the sustainable and high-value utilization of CG-FA,CGFA was used as a carbon source to prepare activated carbon for electric double layer supercapaci-tors through low-temperature alkali fusion coupled KOH activation treatment.The physical and chemical properties and electrochemical properties of activated carbon samples at different KOH dosages were com-pared.Results show that,in the range of mass ratio of deashing carbon(RC)and KOH from 1∶1 to 1∶4,the disorder,specific surface area(SBET),total pore volume(Vtotai),and mesopore occupancy(Vmes/Vtotal)of the activated carbon samples show a gradual enhancement trend with the increase of KOH dosage.The specific capacitance of the activated carbon sample increase with aforementioned parameters.When m(RC)∶m(KOH)=1∶4,the activated carbon sample exhibited an SBET of 1 938.03 m2/g,Vtotal of 1.62 cm3/g,Vmes/Vtotal of 82.82％,mass specific capacitance of 215.56 F/g(current density is 1 A/g),and a rate performance of 88.66％(current density is 1-20 A/g).The energy density of the assembled symmet-ric supercapacitor is 7.23(W·h)/kg(corresponding to a power density of 300 W/kg),and its capacitance retention rate is 100.45％after 100 000 cycles.
coal gasification fine ashcoal-based solid wastesupercapacitoractivated carbonhigher val-ue application
万方数据
维普
