Synthesis of Cobalt-Based Nanomaterials from Organic Precursors

Abstract

Development of efficient and low-cost methods for the production of cobalt and cobalt oxide nanoparticles is of great interest. Such nanoparticles are typically prepared via transformation of precursors under controlled conditions. In the case of organic precursors, the production of said nanoparticles takes place through thermal decomposition of the organic moiety. The decomposition pathway of the precursor is greatly dependent on the type (i.e. inert, reducing or oxidizing) of the gaseous atmosphere prevailing during heating, as well as on the heating schedule itself. The characteristics of the organic group have also an important influence on the structure of the final material. The goal of the current work is to present a comprehensive review of the research work focusing on the synthesis of cobalt-based nanomaterials from activation of organic precursors.

Tuning the Electronic Structure of Cobalt Selenide on Copper Foam by Introducing a Ni Buffer Layer for Highly Efficient Electrochemical Water Splitting

“…A single small peak was observed at 803.75 eV, which was oxidized cobalt due to air oxidation. − The existence of metallic Ni was also identified by analyzing the high-resolution Ni 2p XPS spectrum. The peak at 852.12 eV was assigned to Ni 0 2p 3/2 present in the metallic Ni BL, while peaks at 869.31 and 873.50 eV can assigned as satellite peaks as shown in Figure b. − Two Cu peaks at binding energies of 932.52 and 952.48 eV were observed, which corresponded to Cu 2p 3/2 and Cu 2p 1/2 , respectively, (Figure c; after deconvolution, the peak at 932.2 eV corresponds to Cu 0 and the peak located at 935.09 and 952.46 eV corresponds to Cu 2+ 2p 3/2 and Cu 2+ 2p 1/2 , respectively. The satellite peak was found to be located at 943.74, 954.92, and 964 eV. , The peaks at 56.0 and 57.5 eV shown in Figure d correspond to Se 3d 5/2 and Se 3d 3/2 , respectively, which is evidence of the formation of Se – present in CoSe 2 in the synthesized Cuf@Ni-CoSe 2 catalyst .…”

Morphology-Dependent Electrocatalytic Behavior of Cobalt Chromite toward the Oxygen Evolution Reaction in Acidic and Alkaline Medium

“…Moreover, the two shakeup satellite peaks observed at binding energy values of 784.86 and 801.26 eV correspond to 2p 3/2 and 2p 1/2 , respectively. In the case of CoCr 2 O 4 Hyd and CoCr 2 O 4 Mic, similar types of peaks were observed, which confirmed the +2 and +3 oxidation states of Co, respectively. , However, the shifting of all of the XPS peaks toward higher energy was observed in both the cases with an energy difference of 0.42 and 0.16 eV, respectively, suggesting the morphological dependency because of the strong electronic interaction among the Co and Cr ions. , …”

“…Figure 5a shows the high-resolution XPS spectra of the Co 2p orbital of all of the three samples, which show a similar type of peaks in all three cases. The spectra show that the two spin−orbit coupling peaks correspond to 2p 31,38 However, the shifting of all of the XPS peaks toward higher energy was observed in both the cases with an energy difference of 0.42 and 0.16 eV, respectively, suggesting the morphological dependency because of the strong electronic interaction among the Co and Cr ions. 34,36 The deconvoluted XPS spectra of the Cr 2p orbitals given in Figure 5b show three peaks with binding energies of 574.92, 576.14, and 579.01 eV attributed to the 0, +3, and +6 oxidation states of the chromium 2p 3/2 orbital in CoCr 2 O 4 Wet.…”

Simultaneous Electrodeposition of Ternary Metal Oxide Nanocomposites for High-Efficiency Supercapacitor Applications

“…The Co 2p 3/2 spin orbital was decomposed into two distinct peaks located at the binding energies 780.27 ± 0.36 and 781.76 ± 0.23 eV, which were attributed to Co 3+ and Co 2+ cations, respectively. , Co 2p 3/2 and Co 2p 1/2 were separated by an energy of 14.91 eV, which indicates the presence of a Co 3 O 4 cubic phase. The two satellite peaks of Co 2p at the binding energies 803.66 and 787.02 eV further confirm the presence of cobalt oxides . The Co 2p 1/2 spin orbital gave rise to two distinct peaks located at the binding energies 795.54 ± 0.35 and 797.42 ± 0.24 eV, which also indicated the presence of Co 3+ and Co 2+ cations, respectively.…”

“…The two satellite peaks of Co 2p at the binding energies 803.66 and 787.02 eV further confirm the presence of cobalt oxides. 42 The Co 2p 1/2 spin orbital gave rise to two distinct peaks located at the binding energies 795.54 ± 0.35 and 797.42 ± 0.24 eV, which also indicated the presence of Co 3+ and Co 2+ cations, respectively. The Mn 2p 3/2 spectrum indicated three characteristic peaks—a main peak at 641.61 eV, which was attributed to Mn 4+ , and two peaks at the binding energies 639.06 and 637.21 eV, which were attributed to Mn 3+ and Mn 2+ —along with three satellite peaks at 643.91, 646.09, and 649.20 eV.…”