Synthesis, Structure, and Electrochemical Properties of Some Cobalt Oxalates

Abstract

Transition-metal oxalates have wide applications in magnetics, photoemission, electrochemistry, etc. Herein, using hydrothermal reactions, five cobalt(II) oxalates, Na, and (NH 4 ) 2 Co 2 (C 2 O 4 )F 4 (V) have been synthesized, and their structures are determined from single-crystal X-ray diffraction or Rietveld refinement of powder X-ray diffraction data. Notably, IV and V are identified for the first time. The structures of these cobalt oxalates are versatile, covering 0D, 1D, 2D, and 3D frameworks, while the coordination environments of Co 2+ centers are uniquely distorted octahedra. As representative examples, I and III are investigated as cathode materials for secondary batteries. Both exhibited electrochemical activity despite large cell polarization. The present study enriches the transition-metal oxalate family and provides new options for energy storage materials.

Syntheses and crystal structures of three novel oxalate coordination compounds: Rb2Co(C2O4)2·4H2O, Rb2CoCl2(C2O4) and K2Li2Cu(C2O4)3·2H2O

“…Their magnetic properties are in part due to the oxalato ligand, which is known to facilitate magnetic exchange between transition-metal cations, and the compounds are known to exhibit both ferro-and antiferromagnetic interactions (Miller & Drillon, 2002;Baran, 2014). In addition to their magnetic properties, there have also been numerous studies concerning their electrochemical properties, which have shown promising results (Pramanik et al, 2022;Cai et al, 2020;Yao et al, 2019). Part of the appeal of oxalate-based coordination compounds is due to their high degree of structural diversity, as a result of the oxalate ligand, which can adopt 17 different coordination modes and act as a mono-, bi-, tri-or tetradentate ligand (Rao et al, 2004).…”

Uncovering the S=12 Kagome Ferromagnet within a Family of Metal–Organic Frameworks

“…In the hunt for such novel phenomena of materials, more attention is being paid to magnetic inorganic–organic hybrid systems as promising alternatives to traditionally more widely studied inorganic compounds. − For instance, in the search for unambiguous material realizations of kagome magnets, the ability to separate inorganic kagome layers with organic components is an appealing material design strategy for overcoming the issue of magnetic site disorder that is common in purely inorganic systems. − Metal–organic frameworks (MOFs) make up one such class of inorganic–organic hybrid materials, consisting of metal nodes joined by multitopic organic linkers to form (often porous) crystalline structures …”

Tilting and twisting in a novel perovzalate, K3NaMn(C2O4)3

“…K3NaMn(C2O4)3 (1) was prepared during our exploratory searches for new oxalate-based materials as prospective cathodes for alkali-metal batteries. [11][12][13][14][15][16] The crystal structure was 1). Further synthetic and crystallographic details are given in ESI †.…”