We report on the growth of CoFe2O4/Pt heterostructure and their magnetotransport properties.The magnetoresistance under high magnetic fields exhibits a sign change when the temperature increases from 5 K to 10 K...We report on the growth of CoFe2O4/Pt heterostructure and their magnetotransport properties.The magnetoresistance under high magnetic fields exhibits a sign change when the temperature increases from 5 K to 10 K.The anomalous Hall resistance decreases as the temperature increases.Furthermore,angle-dependent magnetoresistance indicates that the observed magnetotransport behaviors originate from the competition between the spin Hall magnetoresistance and magnetic proximity effect.展开更多
Supported metal catalysts are the backbone of heterogeneous catalysis,playing a crucial role in the modern chemical industry.Metal-support interactions(MSIs)are known important in determining the catalytic performance...Supported metal catalysts are the backbone of heterogeneous catalysis,playing a crucial role in the modern chemical industry.Metal-support interactions(MSIs)are known important in determining the catalytic performance of supported metal catalysts.This is particularly true for single-atom catalysts(SACs)and pseudo-single-atom catalysts(pseudo-SACs),where all metal atoms are dispersed on,and interact directly with the support.Consequently,the MSI of SACs and pseudo-SACs are theoretically more sensitive to modulation compared to that of traditional nanoparticle catalysts.In this work,we experimentally demonstrated this hypothesis by an observed size-dependent MSI modulation.We fabricated CoFe2O4 supported Pt pseudo-SACs and nanoparticle catalysts,followed by a straightforward water treatment process.It was found that the covalent strong metal-support interaction(CMSI)in pseudo-SACs can be weakened,leading to a significant activity improvement in methane combustion reaction.This finding aligns with our recent observation of CoFe2O4 supported Pt SACs.By contrast,the MSI in Pt nanoparticle catalyst was barely affected by the water treatment,giving rise to almost unchanged catalytic performance.This work highlights the critical role of metal size in determining the MSI modulation,offering a novel strategy for tuning the catalytic performance of SACs and pseudo-SACs by fine-tuning their MSIs.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.62525406,T2394473,624B2070,and 62274085)the National Key Research and Development Program of China(Grant No.2022YFA1402404)the Innovation Program for Quantum Science and Technology of China(Grant No.2024ZD0301300)。
摘要We report on the growth of CoFe2O4/Pt heterostructure and their magnetotransport properties.The magnetoresistance under high magnetic fields exhibits a sign change when the temperature increases from 5 K to 10 K.The anomalous Hall resistance decreases as the temperature increases.Furthermore,angle-dependent magnetoresistance indicates that the observed magnetotransport behaviors originate from the competition between the spin Hall magnetoresistance and magnetic proximity effect.
摘要Supported metal catalysts are the backbone of heterogeneous catalysis,playing a crucial role in the modern chemical industry.Metal-support interactions(MSIs)are known important in determining the catalytic performance of supported metal catalysts.This is particularly true for single-atom catalysts(SACs)and pseudo-single-atom catalysts(pseudo-SACs),where all metal atoms are dispersed on,and interact directly with the support.Consequently,the MSI of SACs and pseudo-SACs are theoretically more sensitive to modulation compared to that of traditional nanoparticle catalysts.In this work,we experimentally demonstrated this hypothesis by an observed size-dependent MSI modulation.We fabricated CoFe2O4 supported Pt pseudo-SACs and nanoparticle catalysts,followed by a straightforward water treatment process.It was found that the covalent strong metal-support interaction(CMSI)in pseudo-SACs can be weakened,leading to a significant activity improvement in methane combustion reaction.This finding aligns with our recent observation of CoFe2O4 supported Pt SACs.By contrast,the MSI in Pt nanoparticle catalyst was barely affected by the water treatment,giving rise to almost unchanged catalytic performance.This work highlights the critical role of metal size in determining the MSI modulation,offering a novel strategy for tuning the catalytic performance of SACs and pseudo-SACs by fine-tuning their MSIs.