An efficient preparation and local coordination environment regulation of isolated single-atom sites catalysts(ISASC)for improved activity is still challenging.Herein,we develop a solid phase thermal diffusion strateg...An efficient preparation and local coordination environment regulation of isolated single-atom sites catalysts(ISASC)for improved activity is still challenging.Herein,we develop a solid phase thermal diffusion strategy to synthesize Mn ISASC on highly uniform nitrogen-doped carbon nanotubes by employing MnO_(2) nanowires@ZIF-8 core-shell structure.Under high-temperature,the Mn species break free from core-MnO_(2) lattice,which will be trapped by carbon defects derived from shell-ZIF-8 carbonization,and immobilized within carbon substrate.Furthermore,the poly-dispersed Mn sites with two nitrogen-coordinated centers can be controllably renovated into four-nitrogen-coordinated Mn sites using NH3 treatment technology.Both experimental and computational investigations indicate that the symmetric coordinated Mn sites manifest outstanding oxygen reduction activity and superior stability in alkaline and acidic solutions.This work not only provides efficient way to regulate the coordination structure of ISASC to improve catalytic performance but also paves the way to reveal its significant promise for commercial application.展开更多
基金This work was supported by the National Key R&D Program of China 2017YFA(Nos.0208300 and 0700104)the National Natural Science Foundation of China(Nos.21671180,21802132,22073033,21673087,21873032,and 21903032)+2 种基金startup fund(Nos.2006013118 and 3004013105)from Huazhong University of Science and Technologythe Fundamental Research Funds for the Central Universities(2019kfyRCPY116)the Innovation and Talent Recruitment Base of New Energy Chemistry and Device(B21003).
文摘An efficient preparation and local coordination environment regulation of isolated single-atom sites catalysts(ISASC)for improved activity is still challenging.Herein,we develop a solid phase thermal diffusion strategy to synthesize Mn ISASC on highly uniform nitrogen-doped carbon nanotubes by employing MnO_(2) nanowires@ZIF-8 core-shell structure.Under high-temperature,the Mn species break free from core-MnO_(2) lattice,which will be trapped by carbon defects derived from shell-ZIF-8 carbonization,and immobilized within carbon substrate.Furthermore,the poly-dispersed Mn sites with two nitrogen-coordinated centers can be controllably renovated into four-nitrogen-coordinated Mn sites using NH3 treatment technology.Both experimental and computational investigations indicate that the symmetric coordinated Mn sites manifest outstanding oxygen reduction activity and superior stability in alkaline and acidic solutions.This work not only provides efficient way to regulate the coordination structure of ISASC to improve catalytic performance but also paves the way to reveal its significant promise for commercial application.
