Crystal structure of cobalt hydroxide carbonate Co₂CO₃(OH)₂: density functional theory and X-ray diffraction investigation

Abstract

The crystal structure of cobalt carbonate hydroxide Co2CO3(OH)2, a solid important in materials and environmental science, is investigated using density functional theory (DFT) simulations and powder X-ray diffraction (PXRD) measurements.

Electrooxidation of Alcohols on Mixed Copper–Cobalt Hydroxycarbonates in Alkaline Solution

“…Moreover, we can distinguish three regions in the composition space: Cu‐rich samples are likely to be found in the malachite structure Cu 2 CO 3 (OH) 2 ; this is valid here for samples with a Co substitution of up to 20 %. For nearly equimolar Cu : Co ratios around 50 : 50, the kolwezite structure is expected, which is isostructural to the Cu‐Zn mineral rosasite (Cu,Zn) 2 CO 3 (OH) 2 [55−58] . This can be attributed to the region of ca.…”

“…Whereas the step from rosasite/kolwezite to malachite is very clear (as can be seen by the different patterns in IR, powder X‐Ray diffraction (PXRD), and also in the broad gap we found in elemental analysis, see Figure 1), the transition from kolwezite to the pure cobalt hydroxycarbonate might be relatively smooth ( cf . Table S1 in the Supporting Information)‐in fact, some authors assign cobalt hydroxycarbonate to the rosasite structure type, which would imply unlimited substitutability between the “kolwezite region” and the Co‐rich samples [56,57] …”

“…hydroxycarbonate to the rosasite structure type, which would imply unlimited substitutability between the "kolwezite region" and the Co-rich samples. [56,57] Scanning electron microscopy (SEM) revealed that different morphologies are formed depending on the cobalt content of the sample: Cu-rich samples (Cu : Co 90 : 10, 80 : 20) show a fluffy morphology, larger magnification reveals very regular bodies with a square cross section-cubes and cuboids-that might be part of longer rods, as we know malachite (and Zn-substituted zincian malachite) to form needles. [46] In contrast, Co-rich samples are composed of platelets stacked onto or wedged into one another.…”

Design of a Scalable Dendritic Copper@Ni2+, Zn2+ Cation-Substituted Cobalt Carbonate Hydroxide Electrode for Efficient Energy Storage

“…46 The charge transfer between the adsorbed element and the matrix material is calculated using Bader charge analysis. 47 Details about the characterization, electrochemical measurements, calculations, and additional figures, including XRD patterns, SEM, CV, and GCD can be found in the Supplementary Information.…”

“…Previous studies have proved that DFT-D3 has good accuracy in processing related adsorption systems . The charge transfer between the adsorbed element and the matrix material is calculated using Bader charge analysis …”