Hydrogen generation from formic acid (FA) has received significant attention. The challenge is to obtain a highly active catalyst under mild conditions for practical applications. Here atomic layer deposition (ALD...Hydrogen generation from formic acid (FA) has received significant attention. The challenge is to obtain a highly active catalyst under mild conditions for practical applications. Here atomic layer deposition (ALD) of FeOx was performed to deposit an ultrathin oxide coating layer to a Pd/C catalyst, therein the FeOx coverage was precisely controlled by ALD cycles. Transmission electron microscopy and powder X-ray diffraction measurements suggest that the FeOx coating layer improved the thermal stability of Pd nanoparticles (NPs). X-ray photoelectron spectroscopy measurement showed that deposition of FeOx on the Pd NPs caused a positive shift of Pd3d binding energy. In the FA dehydrogenation reaction, the ultrathin FeOx layer on the Pd/C could considerably improve the catalytic activity, and Pd/C coated with 8 cycles of FeOx showed an optimized activity with turnover frequency being about 2 times higher than the uncoated one. shape as a function of the number of FeOx ALD The improved activities were in a volcanocycles, indicating the coverage of FeOx is critical for the optimized activity. In summary, simultaneous improvements of activity and thermal stability of Pd/C catalyst by ultra-thin FeOx overlayer suggest to be an effective way to design active catalysts for the FA dehydrogenation reaction.展开更多
FeOx electrocatalysts for the oxygen reduction reaction were prepared via one-step synthesis using electron impact with cold plasma as the electron source.Given the low operation temperature,FeOx by plasma technology ...FeOx electrocatalysts for the oxygen reduction reaction were prepared via one-step synthesis using electron impact with cold plasma as the electron source.Given the low operation temperature,FeOx by plasma technology showed a smaller particle size than that prepared via conventional calcination.Notably,electron impact produced more oxygen vacancies and a larger surface area on FeOx,which increased active sites and electronic conductivity,than plasma.Electrochemical investigations indicated that FeOx prepared by plasma exhibited remarkable oxygen reduction reaction activity toward the four-electron electrochemical reduction of oxygen.The results demonstrated that this facile fabrication method is a promising route for developing cost-eff ective and high-performance catalysts to be used in electrochemical applications.展开更多
基金This work was supported by the National Natural Science Foundation of China (No.51402283 and No.21473169), One Thousand Young Talents Program under the Recruitment Program of Global Experts, the Fundamental Research Funds for the Central Universi- ties (No.WK2060030017), and the Startup Funds from University of Science and Technology of China.
文摘Hydrogen generation from formic acid (FA) has received significant attention. The challenge is to obtain a highly active catalyst under mild conditions for practical applications. Here atomic layer deposition (ALD) of FeOx was performed to deposit an ultrathin oxide coating layer to a Pd/C catalyst, therein the FeOx coverage was precisely controlled by ALD cycles. Transmission electron microscopy and powder X-ray diffraction measurements suggest that the FeOx coating layer improved the thermal stability of Pd nanoparticles (NPs). X-ray photoelectron spectroscopy measurement showed that deposition of FeOx on the Pd NPs caused a positive shift of Pd3d binding energy. In the FA dehydrogenation reaction, the ultrathin FeOx layer on the Pd/C could considerably improve the catalytic activity, and Pd/C coated with 8 cycles of FeOx showed an optimized activity with turnover frequency being about 2 times higher than the uncoated one. shape as a function of the number of FeOx ALD The improved activities were in a volcanocycles, indicating the coverage of FeOx is critical for the optimized activity. In summary, simultaneous improvements of activity and thermal stability of Pd/C catalyst by ultra-thin FeOx overlayer suggest to be an effective way to design active catalysts for the FA dehydrogenation reaction.
基金by the National Key Research and Development Program of China(No.2016YFF0102503)National Natural Science Foundation of China(No.21878214)State Key Laboratory of Efficient Utilization for Low Grade Phosphate Rock and Its Associated Resources(No.WFKF2019-03).
文摘FeOx electrocatalysts for the oxygen reduction reaction were prepared via one-step synthesis using electron impact with cold plasma as the electron source.Given the low operation temperature,FeOx by plasma technology showed a smaller particle size than that prepared via conventional calcination.Notably,electron impact produced more oxygen vacancies and a larger surface area on FeOx,which increased active sites and electronic conductivity,than plasma.Electrochemical investigations indicated that FeOx prepared by plasma exhibited remarkable oxygen reduction reaction activity toward the four-electron electrochemical reduction of oxygen.The results demonstrated that this facile fabrication method is a promising route for developing cost-eff ective and high-performance catalysts to be used in electrochemical applications.