近年来,具有丰富活性中心的二维合金高效电催化剂的合成引起人们极大关注.本工作以十六烷基三甲基溴化铵和六羰基钼为结构导向剂合成出三金属钯-银-铜纳米片组装体.用高角度环形暗场扫描透射电子显微镜、透射电子显微镜和X射线衍射仪对...近年来,具有丰富活性中心的二维合金高效电催化剂的合成引起人们极大关注.本工作以十六烷基三甲基溴化铵和六羰基钼为结构导向剂合成出三金属钯-银-铜纳米片组装体.用高角度环形暗场扫描透射电子显微镜、透射电子显微镜和X射线衍射仪对三金属PdAgCu纳米片组装体的形貌和结构进行了表征.结果表明三金属Pd6Ag3Cu2纳米片组装体电催化性能优异,且对乙二醇氧化反应(5696 mA mgPd^(-1))和乙醇氧化反应(4374 mA mgPd^(-1))具有良好的催化稳定性.电催化活性的增强可归因于应变效应、配体效应及双功能效应的协同作用.本文系统研究了三金属电催化剂对C2醇的电催化机理,发现较高的羟基和C2醇浓度有利于乙二醇氧化反应和乙醇氧化反应.展开更多
Atomically ordered intermetallic compounds(OICs)have aroused remarkable interests for wide applications and are considered as very promising materials for electrocatalysis owing to the strict stoichiometry,well-define...Atomically ordered intermetallic compounds(OICs)have aroused remarkable interests for wide applications and are considered as very promising materials for electrocatalysis owing to the strict stoichiometry,well-defined atom binding environment,and the specific crystalline phase.However,the tunable synthesis of the intermetallics remains a giant challenge.Herein,this study reports the preparation of the Pd-Sn OICs composed of an interconnected nanowire network structure with adjustable molar ratios of elements Pd and Sn.The co-reduction of Pd(acac)_(2) and SnCl_(2)·2H_(2)O in ethylene glycol(EG)in the presence of sodium hypophosphite(NaH_(2)PO_(2))as the reducing agent affords OICs of three phases:hexagonal Pd_(3)Sn_(2-)P6_(3)/mmc,orthorhombic PdSn-Pnmb,and orthorhombic PdSn_(2)-Aba_(2).Also,the pure phase can convert to two mixed phases(Pd_(3)Sn_(2)/PdSn and PdSn/PdSn_(2))by just altering the feed ratio.It is found that orthorhombic PdSn-Pnmb OIC has a large electrochemically active surface area(ECSA),excellent electrocatalytic performance(4857 mA mg_(Pd)^(−1)),and outstanding stability toward ethanol oxidation reaction(EOR),which could be attributed to its optimal electronic structure.These results demonstrate that the phase engineering of OICs with desired components is an excellent way for catalysts design.展开更多
基金supported by the National Natural Science Foundation of China(22172084 and 21773133)the World-Class Discipline Program of Shandong Province,China。
文摘近年来,具有丰富活性中心的二维合金高效电催化剂的合成引起人们极大关注.本工作以十六烷基三甲基溴化铵和六羰基钼为结构导向剂合成出三金属钯-银-铜纳米片组装体.用高角度环形暗场扫描透射电子显微镜、透射电子显微镜和X射线衍射仪对三金属PdAgCu纳米片组装体的形貌和结构进行了表征.结果表明三金属Pd6Ag3Cu2纳米片组装体电催化性能优异,且对乙二醇氧化反应(5696 mA mgPd^(-1))和乙醇氧化反应(4374 mA mgPd^(-1))具有良好的催化稳定性.电催化活性的增强可归因于应变效应、配体效应及双功能效应的协同作用.本文系统研究了三金属电催化剂对C2醇的电催化机理,发现较高的羟基和C2醇浓度有利于乙二醇氧化反应和乙醇氧化反应.
基金supported by the National Natural Science Foundation of China(22172084 and 21773133)the World-Class Discipline Program of Shandong Province,China。
文摘Atomically ordered intermetallic compounds(OICs)have aroused remarkable interests for wide applications and are considered as very promising materials for electrocatalysis owing to the strict stoichiometry,well-defined atom binding environment,and the specific crystalline phase.However,the tunable synthesis of the intermetallics remains a giant challenge.Herein,this study reports the preparation of the Pd-Sn OICs composed of an interconnected nanowire network structure with adjustable molar ratios of elements Pd and Sn.The co-reduction of Pd(acac)_(2) and SnCl_(2)·2H_(2)O in ethylene glycol(EG)in the presence of sodium hypophosphite(NaH_(2)PO_(2))as the reducing agent affords OICs of three phases:hexagonal Pd_(3)Sn_(2-)P6_(3)/mmc,orthorhombic PdSn-Pnmb,and orthorhombic PdSn_(2)-Aba_(2).Also,the pure phase can convert to two mixed phases(Pd_(3)Sn_(2)/PdSn and PdSn/PdSn_(2))by just altering the feed ratio.It is found that orthorhombic PdSn-Pnmb OIC has a large electrochemically active surface area(ECSA),excellent electrocatalytic performance(4857 mA mg_(Pd)^(−1)),and outstanding stability toward ethanol oxidation reaction(EOR),which could be attributed to its optimal electronic structure.These results demonstrate that the phase engineering of OICs with desired components is an excellent way for catalysts design.
