Synthesis and Characterization of Porous Magnesium Hydroxide and Oxide Nanoplates

Abstract

Porous magnesium hydroxide nanoplates were prepared directly from commercial bulk magnesium oxide crystals by a simple hydrothermal treatment. These thin plates would aggregate into large spherical particles. The platelike morphology was retained after calcination, and porous magnesium oxide nanoplates were obtained. These plates have a wormhole-like porous structure with high surface area. The obtained materials exhibit bimodal pore size distributions in the mesoporous domain. The aggregation of the nanoplates gives rise to large mesopores with a size of about 36 nm. In addition, each plate has small wormhole mesopores with a size of about 3.7 nm. The growth of magnesium hydroxide nanoplates occurred through a dissolution−recrystallization process. X-ray diffraction and electron diffraction, transmission electron microscopy, scanning electron microscopy, and nitrogen sorption have been employed to characterize these nanoplates. Such porous nanoplates with high surface area and high crystallinity have many promising applications. Moreover, bismuth oxide nanoplates were also produced following a similar method. The formation mechanism of such mesostructures without the use of a template is also discussed.

Fire-retardant and fire-barrier poly(vinyl acetate) composites for sealant application

“…Additionally, the shift in main polymer decomposition may also be due to the volatiles being absorbed on the filler surfaces, hence reducing mass loss until higher temperature is reached. This has been suggested to occur with Mg(OH) 2 as it forms a high surface area inorganic MgO after decomposition [19]. The total amount of water eliminated on thermal dehydration of the Mg(OH) 2 corresponded to 30.8%·wt and is consistent with theoretical value.…”

“…This was due to the presence of fire retardant Mg(OH) 2 and zinc borate in the PVAc composites which caused the deacetylation reaction to shift to higher temperature. The endothermic release of water from both fire retardants absorb heat while water formed and vaporised, cooling the substrate, particularly since Mg(OH) 2 has a relatively high endothermic enthalpy of 1450 J·g -1 [19]. The water loss results in a decrease in the onset of the decomposition as listed in Table 1.…”

Synthesis of Mg(OH)2 micro/nano flowers at room temperature

“…The well-known Scherrer's method is employed to obtain these data [24]. However, before the application of Scherrer's method to the present XRD data, the data are corrected for the machine back-ground effect.…”

Facile approach to synthesize magnesium oxide nanoparticles by using Clitoria ternatea—characterization and in vitro antioxidant studies

“…In the current study, we have employed the plant mediated production of MgO nanoparticles through calcination. This is a simple method among many methods like sol-gel combustion aerosol, laser vapourization, chemical gas phase deposition, hydrothermal techniques (Yu et al 2004;Wang et al 2008;Vandana Singh et al 2015). In the process of size, shape, and crystalline nature of the MgO, nanoparticles are influenced by the parameters such as: temperature, pH and calcination time (Kenneth and Price 1999;Bhatte et al 2011;Suslick et al 1996).…”