Precise catalysis is critical for the high-quality catalysis industry.However,it remains challenging to fundamentally understand precise catalysis at the atomic orbital level.Herein,we propose a new strategy to unrave...Precise catalysis is critical for the high-quality catalysis industry.However,it remains challenging to fundamentally understand precise catalysis at the atomic orbital level.Herein,we propose a new strategy to unravel the role of specific d orbitals in catalysis.The oxygen reduction reaction(ORR)catalyzed by atomically dispersed Pt/Co-doped Ti_(1−x)O_(2) nanosheets(Pt_(1)/Co_(1)-Ti_(1−x)O_(2))is used as a model catalysis.The z-axis d orbitals of Pt/Co-Ti realms dominate the O2 adsorption,thus triggering ORR.In light of orbital-resolved analysis,Pt_(1)/Co_(1)-Ti_(1−x)O_(2) is experimentally fabricated,and the excellent ORR catalytic performance is further demonstrated.Further analysis reveals that the superior ORR performance of Pt_(1)-Ti_(1−x)O_(2) to Co_(1)-Ti_(1−x)O_(2) is ascribed to stronger activation of Ti by Pt than Co via the d-d hybridization.Overall,this work provides a useful tool to understand the underlying catalytic mechanisms at the atomic orbital level and opens new opportunities for precise catalyst design.展开更多
Co-doped ZnO nanoparticles are synthesized by co-precipitation method. The incorporation of Co ions into ZnO wur- zite structure with increasing Co concentrations was followed by X-ray diffraction. Sample structures w...Co-doped ZnO nanoparticles are synthesized by co-precipitation method. The incorporation of Co ions into ZnO wur- zite structure with increasing Co concentrations was followed by X-ray diffraction. Sample structures were further studied by infrared spectra, from which a broad and strong absorption band in the range of 400 - 700 cm-1 and -OH stretching vibrational mode approximately 3400 cm-1 were observed. Ultraviolet-visible measurements showed a red shift of the absorption edge and four peaks at 468, 515, 577 and 629 nm in its reflectance spectra with increasing Co content. Magnetic measurements showed a ferromagnetic behavior for all samples. From the ESR spectra the presence of Co-metal clusters and Co-oxide precipitates are not observed and can be excluded as the origin of ferromagnetic in our samples. The ESR results are supported by UV-Vis measurements data.展开更多
基金supported by the Fundamental Research Funds for the Central Universities(grant nos.2018JBZ107 and 2019RC035)supported financially by the National Natural Science Foundation of China(grant nos.91961125 and 21905019)+1 种基金the Key Program for International S&T Cooperation Projects of China from the Ministry of Science and Technology of China(grant no.2018YFE0124600)the Chemistry and Chemical Engineering Guangdong Laboratory(nos.1932001,1932004,1911020,and 1911023).
文摘Precise catalysis is critical for the high-quality catalysis industry.However,it remains challenging to fundamentally understand precise catalysis at the atomic orbital level.Herein,we propose a new strategy to unravel the role of specific d orbitals in catalysis.The oxygen reduction reaction(ORR)catalyzed by atomically dispersed Pt/Co-doped Ti_(1−x)O_(2) nanosheets(Pt_(1)/Co_(1)-Ti_(1−x)O_(2))is used as a model catalysis.The z-axis d orbitals of Pt/Co-Ti realms dominate the O2 adsorption,thus triggering ORR.In light of orbital-resolved analysis,Pt_(1)/Co_(1)-Ti_(1−x)O_(2) is experimentally fabricated,and the excellent ORR catalytic performance is further demonstrated.Further analysis reveals that the superior ORR performance of Pt_(1)-Ti_(1−x)O_(2) to Co_(1)-Ti_(1−x)O_(2) is ascribed to stronger activation of Ti by Pt than Co via the d-d hybridization.Overall,this work provides a useful tool to understand the underlying catalytic mechanisms at the atomic orbital level and opens new opportunities for precise catalyst design.
文摘Co-doped ZnO nanoparticles are synthesized by co-precipitation method. The incorporation of Co ions into ZnO wur- zite structure with increasing Co concentrations was followed by X-ray diffraction. Sample structures were further studied by infrared spectra, from which a broad and strong absorption band in the range of 400 - 700 cm-1 and -OH stretching vibrational mode approximately 3400 cm-1 were observed. Ultraviolet-visible measurements showed a red shift of the absorption edge and four peaks at 468, 515, 577 and 629 nm in its reflectance spectra with increasing Co content. Magnetic measurements showed a ferromagnetic behavior for all samples. From the ESR spectra the presence of Co-metal clusters and Co-oxide precipitates are not observed and can be excluded as the origin of ferromagnetic in our samples. The ESR results are supported by UV-Vis measurements data.
