物理化学学报
物理化學學報
물이화학학보
ACTA PHYSICO-CHIMICA SINICA
2011年
8期
1875-1880
,共6页
王喜照%符蓉%郑俊生%马建新
王喜照%符蓉%鄭俊生%馬建新
왕희조%부용%정준생%마건신
催化剂%纳米碳纤维%铂纳米粒子%催化活性%燃料电池
催化劑%納米碳纖維%鉑納米粒子%催化活性%燃料電池
최화제%납미탄섬유%박납미입자%최화활성%연료전지
Catalyst%Carbon nanofiber%Pt nanoparticles%Catalytic activity%Fuel cell
采用化学还原法合成了微结构不同的纳米碳纤维(板式、鱼骨式、管式)载铂催化剂(分别记为Pt/p-CNF、Pt/f-CNF、Pt/t-CNF).通过高分辨透射电镜(HRTEM)和X射线衍射(XRD)等分析技术对催化剂的微观结构进行了表征,并利用循环伏安(CV)法分析了催化剂的电化学比表面积(ESA).在此基础上,制备了膜电极(MEA),通过单电池测试了催化剂的电催化性能.结果表明:铂纳米粒子在不同的纳米碳载体上表现出不同的粒径,在板式、鱼骨式和管式纳米碳纤维上的铂纳米粒子平均粒径分别为2.4、2.7和2.8 nm.板式纳米碳纤维载铂催化剂作单电池阳极时表现出良好的电催化性能,其对应的最高功率密度可达0.569 W·cm-2,高于鱼骨式纳米碳纤维载铂催化剂和管式纳米碳纤维载铂催化剂对应的最高功率密度(分别为0.550和0.496 W· cm-2).同时,也制备了碳黑(Pt/XC-72)载铂催化剂.相比于Pt/XC-72,纳米碳纤维载体上的铂纳米颗粒有较小的粒径、较好的分散和较高的催化活性,说明纳米碳纤维是质子交换膜燃料电池(PEMFCs)催化剂的良好载体.
採用化學還原法閤成瞭微結構不同的納米碳纖維(闆式、魚骨式、管式)載鉑催化劑(分彆記為Pt/p-CNF、Pt/f-CNF、Pt/t-CNF).通過高分辨透射電鏡(HRTEM)和X射線衍射(XRD)等分析技術對催化劑的微觀結構進行瞭錶徵,併利用循環伏安(CV)法分析瞭催化劑的電化學比錶麵積(ESA).在此基礎上,製備瞭膜電極(MEA),通過單電池測試瞭催化劑的電催化性能.結果錶明:鉑納米粒子在不同的納米碳載體上錶現齣不同的粒徑,在闆式、魚骨式和管式納米碳纖維上的鉑納米粒子平均粒徑分彆為2.4、2.7和2.8 nm.闆式納米碳纖維載鉑催化劑作單電池暘極時錶現齣良好的電催化性能,其對應的最高功率密度可達0.569 W·cm-2,高于魚骨式納米碳纖維載鉑催化劑和管式納米碳纖維載鉑催化劑對應的最高功率密度(分彆為0.550和0.496 W· cm-2).同時,也製備瞭碳黑(Pt/XC-72)載鉑催化劑.相比于Pt/XC-72,納米碳纖維載體上的鉑納米顆粒有較小的粒徑、較好的分散和較高的催化活性,說明納米碳纖維是質子交換膜燃料電池(PEMFCs)催化劑的良好載體.
채용화학환원법합성료미결구불동적납미탄섬유(판식、어골식、관식)재박최화제(분별기위Pt/p-CNF、Pt/f-CNF、Pt/t-CNF).통과고분변투사전경(HRTEM)화X사선연사(XRD)등분석기술대최화제적미관결구진행료표정,병이용순배복안(CV)법분석료최화제적전화학비표면적(ESA).재차기출상,제비료막전겁(MEA),통과단전지측시료최화제적전최화성능.결과표명:박납미입자재불동적납미탄재체상표현출불동적립경,재판식、어골식화관식납미탄섬유상적박납미입자평균립경분별위2.4、2.7화2.8 nm.판식납미탄섬유재박최화제작단전지양겁시표현출량호적전최화성능,기대응적최고공솔밀도가체0.569 W·cm-2,고우어골식납미탄섬유재박최화제화관식납미탄섬유재박최화제대응적최고공솔밀도(분별위0.550화0.496 W· cm-2).동시,야제비료탄흑(Pt/XC-72)재박최화제.상비우Pt/XC-72,납미탄섬유재체상적박납미과립유교소적립경、교호적분산화교고적최화활성,설명납미탄섬유시질자교환막연료전지(PEMFCs)최화제적량호재체.
Pt nanoparticles supported on carbon nanofibers (Pt/CNFs) with different microstructure,i.e.,platelet CNF (Pt/p-CNF),fish-bone CNF (Pt/f-CNF),and tubular CNF (Pt/t-CNF) were synthesized by achemical reduction method.X-ray diffraction (XRD) and high resolution transmission electron microscope (HRTEM) were applied to characterize the structure of the as-prepared catalysts.The electrochemical surface area (ESA) was studied by cyclic voltammetry (CV).Membrane electrode assemblies (MEAs) with the as-prepared catalysts were fabricated and tested.We found that Pt nanoparticles showed different particle size and dispersion on the three kinds of CNF supports and the mean size of the Pt nanoparticles on p-CNF,f-CNF,and t-CNF was 2.4,2.7,and 2.8 nm,respectively.Single cell testing indicated that the cell with Pt/p-CNF as the anode catalyst gave better performance compared to Pt/f-CNF and Pt/t-CNF.The maximum power density was 0.569 W· cm-2 for Pt/p-CNF,which was higher than that for Pt/f-CNF (0.550 W· cm-2) and Pt/t-CNF (0.496 W· cm-2).Furthermore,Pt nanoparticles supported on carbon black (Pt/XC-72) were also prepared.Pt nanoparticles supported on CNFs have been shown to have a smaller particle size and better dispersion than those on XC-72,and this proves that CNFs can be an efficient electrocatalyst support for proton exchange membrane fuel cells (PEMFCs).