The objective of this study is to investigate the possibility of continuous extrusion forming (Conform process) and microstructural evolution the of Cu-Mg alloy. The results indicate that Conform process can break as-...The objective of this study is to investigate the possibility of continuous extrusion forming (Conform process) and microstructural evolution the of Cu-Mg alloy. The results indicate that Conform process can break as-cast grains and refine the structure, meanwhile. This process can improve the degree of the structure homogeneity. The TEM and EBSD techniques were used to investigate the morphology, grain size and misorientation of the samples at cavity entrance and cavity export. Refined structures after shear deformation include broken grains and subgrains formed by dislocation reconstruction. Due to the relatively high deformation temperature, dynamic recrystallization occurred during deformation. The subgrain rotation nucleation took place, and grain boundary migration resulted in grain growth. However, the coarse grains were refined by anneal twins.展开更多
Currently,single-atom combo catalysts(SACCs)for carbon dioxide reduction reaction(CO_(2)RR)to the formation of HCOOH are still very limited,especially the lanthanide-based SACCs.In this work,the novel SACCs with atomi...Currently,single-atom combo catalysts(SACCs)for carbon dioxide reduction reaction(CO_(2)RR)to the formation of HCOOH are still very limited,especially the lanthanide-based SACCs.In this work,the novel SACCs with atomically dispersed In and Ce active sites were successfully prepared on the nitrogen-doped carbon matrix(InCe/CN).Both aberration-corrected high-angle annular dark-field scanning transmission electron microscopy(AC-HAADF-STEM)images and the extended X-ray absorption fine structure(EXAFS)spectra proved the well-isolated In and Ce atoms.The as-prepared InCe/CN shows a high Faradaic efficiency(FE)(77%)and current density of HCOOH formation(j_(HCOOH))at-1.35 V vs.reversible hydrogen electrode(RHE),much higher than the single atom catalysts.Theoretical calculations have indicated that the introduced Ce single atom sites not only significantly promote electron transfer but also optimize the In-5p orbitals towards higher selectivity towards the HCOOH formation.This work innovatively extends the design of SACCs towards the main group and Ln metals for more applications.展开更多
文摘The objective of this study is to investigate the possibility of continuous extrusion forming (Conform process) and microstructural evolution the of Cu-Mg alloy. The results indicate that Conform process can break as-cast grains and refine the structure, meanwhile. This process can improve the degree of the structure homogeneity. The TEM and EBSD techniques were used to investigate the morphology, grain size and misorientation of the samples at cavity entrance and cavity export. Refined structures after shear deformation include broken grains and subgrains formed by dislocation reconstruction. Due to the relatively high deformation temperature, dynamic recrystallization occurred during deformation. The subgrain rotation nucleation took place, and grain boundary migration resulted in grain growth. However, the coarse grains were refined by anneal twins.
基金We gratefully acknowledge the support from the National Key R&D Program of China(No.2021YFA1501101)the National Natural Science Foundation of China(No.21971117)+11 种基金the National Natural Science Foundation of China/Research Grant Council of Hong Kong Joint Research Scheme(No.N_PolyU502/21)Functional Research Funds for the Central Universities,Nankai University(No.63186005)Tianjin Key Lab for Rare Earth Materials and Applications(No.ZB19500202)111 Project(No.B18030)from Chinathe Outstanding Youth Project of Tianjin Natural Science Foundation(No.20JCJQJC00130)the funding for Projects of Strategic Importance of The Hong Kong Polytechnic University(Project Code:1-ZE2V)Shenzhen Fundamental Research Scheme-General Program(No.JCYJ20220531090807017)the Key Project of Tianjin Natural Science Foundation(No.20JCZDJC00650)the National Postdoctoral Program for Innovative Talents(No.BX20220157)Open Foundation of State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures(No.2022GXYSOF07)Departmental General Research Fund(Project Code:ZVUL)from Department of Applied Biology and Chemical Technology of Hong Kong Polytechnic UniversityHaihe Laboratory of Sustainable Chemical Transformations.
文摘Currently,single-atom combo catalysts(SACCs)for carbon dioxide reduction reaction(CO_(2)RR)to the formation of HCOOH are still very limited,especially the lanthanide-based SACCs.In this work,the novel SACCs with atomically dispersed In and Ce active sites were successfully prepared on the nitrogen-doped carbon matrix(InCe/CN).Both aberration-corrected high-angle annular dark-field scanning transmission electron microscopy(AC-HAADF-STEM)images and the extended X-ray absorption fine structure(EXAFS)spectra proved the well-isolated In and Ce atoms.The as-prepared InCe/CN shows a high Faradaic efficiency(FE)(77%)and current density of HCOOH formation(j_(HCOOH))at-1.35 V vs.reversible hydrogen electrode(RHE),much higher than the single atom catalysts.Theoretical calculations have indicated that the introduced Ce single atom sites not only significantly promote electron transfer but also optimize the In-5p orbitals towards higher selectivity towards the HCOOH formation.This work innovatively extends the design of SACCs towards the main group and Ln metals for more applications.