以市售的煤质活性炭(AC)为原材料,进行氮掺杂/硝酸两步法改性,采用扫描电镜(SEM)、红外光谱(FT-IR)、BET比表面积和电化学分析等手段对改性前后AC的表面性质和电化学性能进行探究。通过电吸附实验及吸附动力学模型研究其吸附机理。结果表明:经过尿素改性后再进行硝酸改性的AC(H-AC)在表面形貌方面得到了更大的比表面积和更丰富的孔隙结构;电化学性能方面比电容显著增加,内阻明显降低,亲水性能获得大幅提升,这些优点对于将其制备为电极表现出了非凡的潜力。H-AC在最优条件下比表面积为856.073m2/g、孔容为0.648cm3、且制得的电极比电容为370.41F/g,该电极在Cu2+初始浓度为80mg/L、工作电压1.5V、极板间距6mm的条件下Cu2+离子的去除率达到74.56%。
Commercially available coal-based activated carbon (AC) was used as raw material for nitrogen doping/nitric acid two-step modification,and the surface properties and electrochemical properties of AC before and after modification were investigated by means of SEM,FT-IR,BET,and electrochemical analyses.The adsorption mechanism was investigated by electrosorption experiments and adsorption kinetic modeling.It was found that the H-AC,AC modified first by urea and then by nitric acid,exhibited a larger specific surface area and a richer pore structure in terms of surface morphology.The electrochemical properties of the modified H-AC showed a significant increase in specific capacitance,a noticeable decrease in internal resistance,and a substantial increase in hydrophilicity,demonstrating a remarkable potential for the preparation of electrodes.Under the optimal conditions,the surface area of H-AC was 856.073m3/g,the specific surface area of H-AC was 856.073m2/g,the pore volume was 0.648cm3,and the specific capacitance of the fabricated electrode was 370.41F/g.The removal rate of Cu2+ ions of the electrode reached 74.56% at an initial concentration of Cu2+ of 80mg/L,an operating voltage of 1.5V,and a plate spacing of 6mm.
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基金资助
陕西省科技厅工业攻关项目(2020SF-435);榆林市科技局项目(CXY-2020)
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