Shape-controlled synthesis of cobalt oxide nanocrystals using cobalt acetylacetonate

Solvothermal Synthesis and Characterization of Flower-Like b-In2S3 Microparticles

“…After a certain time of reaction at elevated temperature and pressure the stability of the complex decreased and S 2-(obtained by the dissociation of thiourea at high temperature) immediately reacted with the aforesaid complexes to form In2S3 microsphere; the volatile organic ligand was gradually lost (as the boiling point of acetylacetone is 140 °C at normal pressure and temperature). Flake-like pattern (inside the flower) may be explained by considering a non-equilibrium growth phenomenon via a diffusion-limited monomer-cluster aggregation [24,25]; this concept matches well with the progressive formation of each flake-like pattern as a function of reaction time (12 h as compared to 10 h). The structure-directing ability of acetylacetone obviously helps in this growth phenomenon.…”

Ligand-Stabilized CoO and NiO Nanoparticles for Spintronic Devices with Antiferromagnetic Insulators

“…It was obvious that the average particle sizes estimated from XRD patterns were consistent with the values obtained from TEM images. From the above study, it can be concluded that the chemical decomposition induced by the MW irradiation was not very different from those generated by the conventional thermal heating of the cobalt precursors, − , although the crystal structure of these precursors was geometrically different from each other, − for example, tetraaqua­bis­(acetato­oxygen)­cobalt­(II) as the acetate precursor, catena-tetra­aqua­tetrakis­(μ2 formate O,O′)­dicobalt­(II) as the formate precursor, and anhydrous mononuclear bis­(2,4-pentane­dionato)­cobalt­(II) as the acetylacetonate precursor. Thus, the difference of cobalt precursors does not significantly affect the particle size and morphology of the CoO nanoparticles.…”

“…Furthermore, in the presence of oleic acid (OA) and oleylamine (OAm), which play the roles of nanoparticle stabilizers, Sun et al have investigated the heating method to synthesize monodisperse iron oxide nanoparticles, mainly magnetite (Fe 3 O 4 ) and MFe 2 O 4 (M = Co and Mn as two examples) nanoparticles with diameters that are tunable from 3 to 20 nm. On the basis of their research, it is worth mentioning that the organic solvent prevents the formation of oxide or hydroxide, and the use of tuned mixtures of OA and OAm leads to size- and shape-controlled syntheses, which have been reported previously. − In addition, trioctyl­phosphine oxide (TOPO) or trioctyl­phosphine (TOP) has been used to prepare monodisperse metal oxide nanoparticles in the presence of OAm. ,,− In particular, the synthesis of Ni/NiO core–shell nanoparticles in the presence of TOPO has been reported by several groups. , The magnetic properties of these core–shell nanoparticles are of interest because ferromagnetic Ni is converted to antiferromagnetic NiO, which can generate the exchange bias mentioned above.…”

General Synthesis of Lead-Free Metal Halide Perovskite Colloidal Nanocrystals in 1-Dodecanol

“…In this study, we report a general and efficient synthetic route of lead-free bismuth/antimony halide perovskite NCs by using 1-dodecanol as both the solvent and capping agent. 1-Dodecanol is a polar solvent that can act as the structure-directing agent to largely enhance the monodispersity and size uniformity of as-synthesized bismuth/antimony halide perovskite NCs. − In addition, 1-dodecanol is cheaper and more environmentally friendly than ODE . Moreover, trimethylsilyl halides were chosen as halide precursors in as-proposed synthetic systems, which can enable the regulation of halide compositions in as-synthesized NCs. , As a result, a series of all-inorganic and organic–inorganic bismuth/antimony halide perovskite A 3 B 2 X 9 (A = Cs, Rb, or CH 3 NH 3 ; B = Bi or Sb; X = Cl, Br, or I) NCs can be synthesized and the band gaps of as-synthesized NCs can be tuned.…”