Solvothermal Synthesis of CoO, Co₃O₄, Ni(OH)₂ and Mg(OH)₂ Nanotubes

Abstract

In this paper, CoO, Co3O4, Ni(OH)2, and Mg(OH)2 nanotubes were synthesized by solvothermal treatment of corresponding colloidal hydroxide. These nanotubes were characterized by powder X-ray diffraction (XRD), selected area electron diffraction (SAED), and transmission electron microscopy (TEM). According to the time-dependent morphology evolution, it is likely that the growth is governed by a solution−solid process. Advantages of this method include that it is a simple and general process without the need for a catalyst, surfactant, or template, which makes it low cost, and that the raw materials are readily available. On the basis of the above results, other metal hydroxides with layered structure are therefore potentially capable of forming nanotubes.

Probing core and shell contributions to exchange bias inCo/Co3O4nanoparticles of controlled size

“…1(f). The obtained values are consistent with the previously reported results [34,37] lines in 1(f)] [34,38], being higher and lower than in bulk, respectively. This reveals significant tensile strains on the Co cores of the particles caused by the formation of the oxide phase at the shell.…”

Rapid surfactant-free synthesis of Mg(OH)2 nanoplates and pseudomorphic dehydration to MgO

“…The nanostructured MgIJOH) 2 begins to lose weight at 548 K and reaches a stable final mass by 678 K. The DTA curve reaches a maximum at 665 K and confirms that the reaction process is endothermic. Mass spectra confirm that water is the sole gaseous species evolved during heating and dehydration would thus be expected to proceed via the reverse of the reaction given by eqn (1). It has been previously reported that when the particle size of MgIJOH) 2 is decreased to the nanoscale level (25-200 nm), then the decomposition temperature can be reduced by over 200 K to 553-603 K (as measured by TGA performed under flowing N 2 ).…”

Three-dimensional roselike α-Ni(OH)2 assembled from nanosheet building blocks for non-enzymatic glucose detection

“…In the past few years, Ni(OH) 2 with different structures, such as nanowire [27,28], nanoflakes [29], nanotubes [30], nanosheets [31], nano/microspheres [32,33], and hollow nano/ microspheres [34] have been successfully fabricated by a variety of methods. Recently, large quantities of "flowerlike" Ni(OH) 2 materials have been reported.…”