CAJ | 학술논문

以三聚氰胺、间苯二酚、甲醛为原料,采用溶胶-凝胶法、冷冻干燥等步骤制备出三聚氰胺-间苯二酚-甲醛( MR)干凝胶；并以所制炭气凝胶为载体浸渍硝酸钴,经氮气中高温炭化,得到钴复合氮掺杂的炭气凝胶。考察间苯二酚和三聚氰胺比例、凝胶pH值及炭化条件等对气凝胶结构和催化氧还原活性的影响,采用XRD、XPS、低温氮气吸脱附等方法研究催化剂的结构。随pH值增加,MR气凝胶的介孔分布向小孔移动；当M/R物质的量比为6：1时,其介孔分布为3.0~4.0 nm。钴复合炭气凝胶多孔结构中存在均匀分布Co金属颗粒和管状炭,Co金属颗粒粒径随炭化温度升高而增加。采用旋转圆盘电极研究催化剂在0.5 mol/L H2 SO4溶液中的电化学性能,结果表明催化剂具有良好的氧还原活性。
이삼취청알、간분이분、갑철위원료,채용용효-응효법、냉동간조등보취제비출삼취청알-간분이분-갑철( MR)간응효；병이소제탄기응효위재체침지초산고,경담기중고온탄화,득도고복합담참잡적탄기응효。고찰간분이분화삼취청알비례、응효pH치급탄화조건등대기응효결구화최화양환원활성적영향,채용XRD、XPS、저온담기흡탈부등방법연구최화제적결구。수pH치증가,MR기응효적개공분포향소공이동；당M/R물질적량비위6：1시,기개공분포위3.0~4.0 nm。고복합탄기응효다공결구중존재균균분포Co금속과립화관상탄,Co금속과립립경수탄화온도승고이증가。채용선전원반전겁연구최화제재0.5 mol/L H2 SO4용액중적전화학성능,결과표명최화제구유량호적양환원활성。
Melamine-resorcinol-formaldehyde ( MR) aerogels were prepared by the sol-gel polymerization of formaldehyde with melamine and resorcinol using NaOH as catalyst, followed by freeze-drying. Co-loaded carbon aerogels were obtained by impregna-ting the MR aerogels with Co( III) tert-butanol solution, followed by carbonization in N2 . The effects of the molar ratios of mela-mine to resorcinol ( M/R) , pH, Co content and carbonization temperature on the microstructure of the aerogels were investigated. It was found that the microstructure of the MR aerogels could be adjusted by the M/R ratio and pH. The mesopore size of the MR aer-ogels decreased with increasing pH and the mesopore size was in the range of 3-4nm when the M/R was 6:1. There were some gra-phitic nano-ribbons in Co-loaded carbon aerogels. The metal average particle size in the carbon aerogels increased from 5. 2 to 6. 2 nm when the carbonization temperature was increased from 700 to 900℃. The electrochemical properties of the Co-loaded car-bon aerogels as catalysts in the oxygen reduction reaction were evaluated by a rotating disc electrode technique in an O2-saturated 0. 5 mol/L H2 SO4 solution, and the catalysts showed a good electrocatalytic activity for the reaction.