Three sandwich-like[Ln_(2)Fe_(2)(B-α-FeW_9O_(34))_(2)]^(10-) clusters(Ln_(2)Fe_(4),Ln=Dy(1),Ho(2),and Y(3)) were obtained by reacting Na_9[B-α-SbW_9O_(33)],Ln_(2)O_(3),FeCl_(3)·6H_(2)O and KH_(2)PO_(4).The[B-α...Three sandwich-like[Ln_(2)Fe_(2)(B-α-FeW_9O_(34))_(2)]^(10-) clusters(Ln_(2)Fe_(4),Ln=Dy(1),Ho(2),and Y(3)) were obtained by reacting Na_9[B-α-SbW_9O_(33)],Ln_(2)O_(3),FeCl_(3)·6H_(2)O and KH_(2)PO_(4).The[B-α-FeW_9O_(34)]^(11-) units were formed via the in situ conversion of lacunary polyoxometalates(POM)[B-α-SbW_9O_(33)]^(9-)and the Ln^(3+)ions were generated from the slow dissolution of Ln_(2)O_(3),both of which play important roles in the synthesis of Ln_(2)Fe_(4).Ln_(2)Fe_(4) is the first 3d-4f cluster assembled from d-metal heteroatom-containing POM.The Dy_(2)Fe_(4) cluster exhibits single-molecule magnet properties with an 80 K energy barrier in an optimal DC field.Cyclic voltammetry tests and controlled-potential coulometry experiments show that the polyoxometalate Fe heteroatom in clusters 1-3 is also electrochemically active.展开更多
A comprehensive understanding of excited-state dynamics of semiconductor quantum dots or nanomaterials at the atomic or molecular level is of scientific importance.Pure inorganic(or non-covalently protected)seimicondu...A comprehensive understanding of excited-state dynamics of semiconductor quantum dots or nanomaterials at the atomic or molecular level is of scientific importance.Pure inorganic(or non-covalently protected)seimiconductor molecular nanoclusters with atomically precise structure are contributive to establish accurate correlation of excited-state dynamics with their composition/structure,however,the related studies are almost blank because of unresolved solvent dispersion issue.Herein,we designedly created the largest discrete chalcogenide seimiconductor molecular nanoclusters(denoted P2-CuMSnS,M=In or/and Ga)with great dispersibility,and revealed an interesting intracluster“core–shell”charge transfer relaxation dynamics.A systematic red shift in absorption spectra with the gradual substitution of In by Ga was experimentally and computationally investigated,and femtosecond transient absorption measurements further manifested there were three ultrafast processes in excited-state dynamics of P2 nanoclusters with the corresponding amplitudes directed by composition variation.Current results hold the great promise of the solution-processible applications of semiconductor-NC-based quantum dots and facilitate the development of atomically precise nano-chemistry.展开更多
基金supported by the National Natural Science Foundation of China(Nos.21871224,92161104,92161203 and 21721001)Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM No.RD2021040301)。
文摘Three sandwich-like[Ln_(2)Fe_(2)(B-α-FeW_9O_(34))_(2)]^(10-) clusters(Ln_(2)Fe_(4),Ln=Dy(1),Ho(2),and Y(3)) were obtained by reacting Na_9[B-α-SbW_9O_(33)],Ln_(2)O_(3),FeCl_(3)·6H_(2)O and KH_(2)PO_(4).The[B-α-FeW_9O_(34)]^(11-) units were formed via the in situ conversion of lacunary polyoxometalates(POM)[B-α-SbW_9O_(33)]^(9-)and the Ln^(3+)ions were generated from the slow dissolution of Ln_(2)O_(3),both of which play important roles in the synthesis of Ln_(2)Fe_(4).Ln_(2)Fe_(4) is the first 3d-4f cluster assembled from d-metal heteroatom-containing POM.The Dy_(2)Fe_(4) cluster exhibits single-molecule magnet properties with an 80 K energy barrier in an optimal DC field.Cyclic voltammetry tests and controlled-potential coulometry experiments show that the polyoxometalate Fe heteroatom in clusters 1-3 is also electrochemically active.
基金The authors acknowledge financial support from the National Natural Science Foundation of China(Nos.21671142,11804084 and 21875150)the Jiangsu Province Natural Science Fund for Distinguished Young Scholars(No.BK20160006)+2 种基金the 111 Project(No.D20015)the Project of Scientific and Technologic Infrastructure of Suzhou(No.SZS201905)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).The authors also thank Dr.D.C.Ma at Analytical and Testing Center,Sichuan University for technical help with the Material Studio calculations.
文摘A comprehensive understanding of excited-state dynamics of semiconductor quantum dots or nanomaterials at the atomic or molecular level is of scientific importance.Pure inorganic(or non-covalently protected)seimiconductor molecular nanoclusters with atomically precise structure are contributive to establish accurate correlation of excited-state dynamics with their composition/structure,however,the related studies are almost blank because of unresolved solvent dispersion issue.Herein,we designedly created the largest discrete chalcogenide seimiconductor molecular nanoclusters(denoted P2-CuMSnS,M=In or/and Ga)with great dispersibility,and revealed an interesting intracluster“core–shell”charge transfer relaxation dynamics.A systematic red shift in absorption spectra with the gradual substitution of In by Ga was experimentally and computationally investigated,and femtosecond transient absorption measurements further manifested there were three ultrafast processes in excited-state dynamics of P2 nanoclusters with the corresponding amplitudes directed by composition variation.Current results hold the great promise of the solution-processible applications of semiconductor-NC-based quantum dots and facilitate the development of atomically precise nano-chemistry.