Colloidal stability of Ni(OH)₂ in water and its dispersion into a ceramic matrix from the reaction media to obtain Ni/Al₂O₃ materials

Influence of ultrasound on the instantaneous synthesis of tridimensional α-Ni(OH)2 nanostructures and derived NiO nanoparticles

“…Under these conditions, the particle size distribution was determined for both powders by DLS. 22 The mean particle size of ANHUS-1 is 190 nm in number and 295 nm in volume, while the mean values for the population of ANHUS-5 nanostructures are 530 nm and 615 nm in number and volume, respectively. 4, where the particle size distributions in both number (Fig.…”

“…Under these conditions and the effects of ultrasound, the ammonia concentration decreases due to a degassing process, reducing the pH of the solution and leading to the precipitation of β-NiIJOH) 2 powders. 22 The general scheme for these reactions is as follows:…”

“…Some recent papers have proven that the decrease of crystallite size and the increase of structural defects (turbostraticity, cation vacancies and/or stacking faults) improve the electrochemical activity of this material. [20][21][22] The crystallographic structure of this metastable phase is not well described since the interlaminar space depends on the type of inclusion present in the structure, which normally varies from 7 to 8 Å. [11][12][13][14][15][16][17][18] Some other characteristics of 3D hierarchical nanostructures of nickel-based compounds are now on focus due to the chemical and magnetic activity of metallic nickel.…”

“…On the other hand, α-NiIJOH) 2 is a metastable phase due to a lack of hydroxyl groups within its structure that force foreign anions to be intercalated within the nickel-hydroxyl layers to maintain its electroneutrality, leading to the formation of a hydrotalcite-like structure. [20][21][22] The crystallographic structure of this metastable phase is not well described since the interlaminar space depends on the type of inclusion present in the structure, which normally varies from 7 to 8 Å. 23,24 The presence of these anions, along with water molecules within the structure, results in a turbostratic phase whose basal planes are not perfectly aligned along the c-axis but slightly deviated from one another.…”

Facile NiOx Sol-Gel Synthesis Depending on Chain Length of Various Solvents without Catalyst for Efficient Hole Charge Transfer in Perovskite Solar Cells

“…Hence, a divalent alcohol–based solvent (having one more hydroxyl group than a monohydric alcohol–based solvent) was selected to synthesize the NiO x sol-gel without a toxic catalyst. It was observed that the nickel precursor did not precipitate, and the stability of the solution improved [46,47,48,49,50]. We found that the results of this experiment were based on the evaporation rate effect of the boiling points of the different solvents [51,52,53,54,55,56,57,58,59].…”