CAJ | 학술논문

通过氢气还原改性和浓硝酸氧化处理对石油焦基活性炭(ACs)进行改性.采用氮气吸附和脱附等温线计算改性ACs的BET比表面积、 DFT孔径分布及孔容,以XPS方法表征改性ACs的表面含氧官能团种类及含量,改性ACs的电化学性能通过直流循环充放电、循环伏安等表征.结果表明:浓硝酸处理后,ACs比表面积和孔容均稍有减少,表面含氧官能团和比电容明显增加,内阻和自放电显著增大;氢气改性后,ACs比表面积和孔容亦稍有减少,孔径分布的变化使比电容明显增加,氧化官能团的减少降低了内阻并减少了自放电.即,氢气改性ACs的电化学性能明显提高,增加了比电容,降低了内阻和自放电.
통과경기환원개성화농초산양화처리대석유초기활성탄(ACs)진행개성.채용담기흡부화탈부등온선계산개성ACs적BET비표면적、 DFT공경분포급공용,이XPS방법표정개성ACs적표면함양관능단충류급함량,개성ACs적전화학성능통과직류순배충방전、순배복안등표정.결과표명:농초산처리후,ACs비표면적화공용균초유감소,표면함양관능단화비전용명현증가,내조화자방전현저증대;경기개성후,ACs비표면적화공용역초유감소,공경분포적변화사비전용명현증가,양화관능단적감소강저료내조병감소료자방전.즉,경기개성ACs적전화학성능명현제고,증가료비전용,강저료내조화자방전.
Petroleum coke-based activated carbons(ACs)were modified through H2 reduction and HNO3 oxidation. Pore structures and surface chemistry of the ACs were characterized by N2 adsorption and X-ray photoelectron spectroscopy. The Brunauer-Emmett-Teller surface areas of ACs were slightly decreased after such treatment. Although surface oxygen groups(especially carbonyl groups)were generated when ACs were treated by HNO3, electric double layer capacitance, internal resistance(IR), equivalent series resistance(ESR), and self-discharge of an AC electrode exhibited a remarkable increase. At the same time, the number of surface oxygen groups of ACs modified by H2 remarkably decreased and the capacitance was markedly increased , while IR, ESR, and self-discharge decreased. This reduction modification of ACs is beneficial in improving electrochemical properties and probably provides suitable pores for electrolyte to penetrate electrochemically.