功能材料
功能材料
공능재료
JOURNAL OF FUNCTIONAL MATERIALS
2015年
1期
1148-1152
,共5页
张雪乔%田浩杞%叶芝祥%刘盛余
張雪喬%田浩杞%葉芝祥%劉盛餘
장설교%전호기%협지상%류성여
Pd%甲醇%催化氧化%碱土助剂
Pd%甲醇%催化氧化%堿土助劑
Pd%갑순%최화양화%감토조제
palladium%methanol%catalytic oxidation%alkaline earth promot
采用等体积浸渍法制备了一系列负载型Pd+M(M=MgO、CaO、SrO、BaO )催化剂,运用BET、CO-化学吸附、XRD、H2-TPR 和 XPS 等表征手段对催化剂进行了表征,并考察其对甲醇的催化氧化性能.结果表明,添加碱土金属可使 Pd 粒子高度分散,催化剂表面易还原氧物种量增多,还原速率加快;XPS分析可知,碱土金属可增强 Pd-Ce 间相互作用,促使Pd向氧化态过渡,同时增加催化剂表面 Ce3+浓度,改善催化剂的氧化还原性能,进而提高催化剂的催化活性.助催化效果递变规律为 BaO>CaO>MgO>SrO.
採用等體積浸漬法製備瞭一繫列負載型Pd+M(M=MgO、CaO、SrO、BaO )催化劑,運用BET、CO-化學吸附、XRD、H2-TPR 和 XPS 等錶徵手段對催化劑進行瞭錶徵,併攷察其對甲醇的催化氧化性能.結果錶明,添加堿土金屬可使 Pd 粒子高度分散,催化劑錶麵易還原氧物種量增多,還原速率加快;XPS分析可知,堿土金屬可增彊 Pd-Ce 間相互作用,促使Pd嚮氧化態過渡,同時增加催化劑錶麵 Ce3+濃度,改善催化劑的氧化還原性能,進而提高催化劑的催化活性.助催化效果遞變規律為 BaO>CaO>MgO>SrO.
채용등체적침지법제비료일계렬부재형Pd+M(M=MgO、CaO、SrO、BaO )최화제,운용BET、CO-화학흡부、XRD、H2-TPR 화 XPS 등표정수단대최화제진행료표정,병고찰기대갑순적최화양화성능.결과표명,첨가감토금속가사 Pd 입자고도분산,최화제표면역환원양물충량증다,환원속솔가쾌;XPS분석가지,감토금속가증강 Pd-Ce 간상호작용,촉사Pd향양화태과도,동시증가최화제표면 Ce3+농도,개선최화제적양화환원성능,진이제고최화제적최화활성.조최화효과체변규률위 BaO>CaO>MgO>SrO.
A series of Pd+M(M=MgO,CaO,SrO,BaO)catalysts was prepared by impregnation method.Specif-ic surface area measurements (BET),CO-chemisorption,X-ray diffraction (XRD),H2-temperature-pro-grammed reduction (H2-TPR),were used to characterize the effect of alkaline earth metal on the physicochemi-cal properties of the catalysts.Their catalytic activity towards methanol oxidation was evaluated.The results show that the addition of alkaline earth metal increases palladium highly dispersed and enhances the amount of active oxygen.X-ray photoelectron spectroscopy (XPS)result shows that the electron effects between Pd and support was improved.It was favorable for maintaining Pd in a higher oxidized state and increasing the concen-tration of Ce3+on the catalyst surface,which led to a better redox property.The excellent redox property helped to improve the catalytic activities toward methanol over Pd-based catalysts.The aid catalytic activity was follow-ing the order:BaO>CaO>MgO>SrO.