Premium
Multifaceted Bicubane Co 4 Clusters: Magnetism, Photocatalytic Oxygen Evolution, and Electrical Conductivity
Author(s) -
Xie WanFeng,
Guo LingYu,
Xu JiaHeng,
Jagodič Marko,
Jagličić Zvonko,
Wang WenGuang,
Zhuang GuiLin,
Wang Zhi,
Tung ChenHo,
Sun Di
Publication year - 2016
Publication title -
european journal of inorganic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 1434-1948
DOI - 10.1002/ejic.201600510
Subject(s) - chemistry , isostructural , photocatalysis , catalysis , magnetism , cobalt , conductivity , crystallography , density functional theory , cluster (spacecraft) , halogen , intramolecular force , photochemistry , inorganic chemistry , computational chemistry , stereochemistry , crystal structure , organic chemistry , physics , quantum mechanics , alkyl , computer science , programming language
The use of 1‐(hydroxymethyl)‐3,5‐dimethylpyrazole (HL), a functionalized pyrazole ligand, to assemble with CoX 2 (X = Cl or Br) in the presence of triethylamine under low‐temperature solvothermal conditions gave rise to two tetranuclear cobalt(II) clusters, [Co 4 L 6 X 2 ] [X = Cl ( 1 ), Br ( 2 )]. Both Co II 4 clusters are isostructural and protected by four µ 2 ‐ N 1 : O 2 and two µ 3 ‐ N 1 : O 3 L – as well as terminal X anions to form a face‐shared open bicubane structural motif. Magnetic susceptibility measurements indicated that there is an intramolecular antiferromagnetic interaction between four Co II atoms in 1 and 2 . Although the core motif of 1 and 2 is not classic Co 4 O 4 monocubane, both are active catalysts for water oxidation, and their relative O 2 ‐evolution rates are dependent on the halogen terminal ligands, which is also supported by spin‐polarized density functional theory (DFT) calculations. Both clusters exhibit semiconductor behavior with σ values on the 10 –9 S cm –1 scale at room temperature; however, mechanical iodine doping results in up to an astonishing 10 5 ‐fold maximum enhancement of solid‐state conductivity relative to the undoped samples. This work therefore presents a new core type of cobalt cluster that possesses photocatalytic oxygen‐evolution capabilities, provides new insight into the catalysis‐related mechanism based on the relative oxygen‐evolution efficiency, and applies the iodine‐doping strategy to boost the conductivity of cluster compounds.