摘要
采用化学原位聚合法制备聚吡咯/活性炭(AC)复合物,在惰性气氛进行热处理,制备了氮掺杂活性炭(NAC)。利用化学浸渍还原法制备AC和NAC载铂催化剂,并对比分析他们的氧还原催化性能。氮掺杂处理明显降低了活性炭的比表面积,但因其改善了活性炭水分散性和表面活性,铂在NAC表面沉积和分布较在AC载体表面更均匀。尤其经900℃炭化处理获得的氮掺杂活性炭NAC900,源于其微孔的高比表面积和含氮官能团共同作用,使铂粒子多以尺寸小于5 nm的粒子均匀沉积分布于载体表面,且铂担载量高。循环伏安曲线分析表明,与活性炭载铂催化剂(Pt-AC)相比,氮掺杂活性炭载铂催化剂(Pt-NAC900)的氧还原峰电位更正,氧还原峰电流为前者两倍,且峰电流随循环次数的衰减更低。结果表明,通过对传统炭材料活性炭进行氮掺杂处理,能够增强其载铂催化剂氧还原催化性能。
Two nitrogen-doped activated carbons (NACs) were prepared by the in-situ polymerization of pyrrole in activated car-bon (AC),followed by carbonization at 700 or 900 ℃.Platinum was loaded onto the AC and NACs by impregnation with a H2 PtCl6 solution followed by chemical reduction with excess NaBH4 . The oxygen reduction reaction ( ORR) performance of the Pt- loaded AC and NACs were investigated. Results indicate that the nitrogen doping decreases the specific surface area, but improves water dispersibility and surface activity,which makes the platinum loading more uniform on the NACs than on the AC. Of the three sample the material with the highest density of platinum particles with sizes less than 5 nm uniformly distributed on the surface was NAC900,and the platinum loading was higher than that on AC and NAC700. The ORR catalytic performance of the Pt-loaded acti-vated carbons was enhanced by the nitrogen doping. Pt-NAC900 exhibits the most positive ORR peak and the highest ORR peak cur- rent, and its ORR peak current decay is the slowest of the three samples.
出处
《新型炭材料》
SCIE
EI
CAS
CSCD
北大核心
2016年第3期287-292,共6页
New Carbon Materials
基金
国家自然科学基金(51102126)
辽宁省高校创新团队(LT2014007)
辽宁省自然科学基金(201502063)~~
关键词
氮掺杂
活性炭
铂
氧还原反应
Nitrogen doping
Activated carbon
Platinum
Oxygen reduction reaction