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Facile Hydrothermal Fabrication of Nano-Oxide Hollow Spheres using Monosaccharides as Sacrificial Templates.

Abdelaal HM - ChemistryOpen (2014)

View Article: PubMed Central - PubMed

Affiliation: Ceramics Department, The National Research Centre Al-Buhouth St. Dokki, Cairo (Egypt).

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The synthesis was achieved via a facile one-pot hydrothermal strategy with the use of simple sugars (glucose or fructose) as sacrificial templates (Scheme 1)... More precisely, the synthesis of glucose- and fructose-derived carbonaceous spheres via hydrothermal hydrolysis in a closed system (100 mL Teflon-lined stainless steel autoclave) was investigated... Shrinkage occurs after thermal treatment of C@SiO2 precursor composites at 550 °C for 5 h; the size decreases by approximately 65 to 80 %... In addition, it was found that PHSNPs vary between approximately 25 and 50 nm in diameter as shown in TEM images... The removal of the interior carbonaceous cores via heat treatment through oxidation in air yields free-standing hollow crystalline oxide spheres... Ball-in-ball (bnb) hollow structures were found within the final products without any further synthetic steps (Scheme 3)... We believe that the key to success in fabricating hollow metal oxide spheres, using glucose or fructose as sacrificial templates, is the fact that their derived carbonaceous sphere surface is rich in oxygen functionalities (e.g. OH and C=O)... The last part of the thesis concerns similarities and differences between glucose and fructose as sacrificial templates for the fabrication of the inorganic oxide hollow spheres... In this part, significant differences between fructose and glucose templates were observed... Applying fructose as a template allows for a lower reaction temperature and shorter reaction time compared with the reaction using glucose... Overall, this work shows that using simple sugars as sacrificial templates in a one-pot hydrothermal method is an efficient means of fabricating micro- and nano-sized oxides with hollow structures... We have applied fructose as a new sacrificial template for fabricating Cr2O3, α-Fe2O3, Co3O4, NiO, and ZnO with hollow structures for the first time, to the best of our knowledge... Glucose has also been successfully used for fabricating the same hollow-sphere oxides... Important factors critical to fine-tune the final particle size and shape are temperature, reaction time, and the addition of acetic acid as a catalyst... Lastly, we have shown that the most significant difference between the two monosaccharides is the decrease in reaction time and energy when applying fructose as the sacrificial template.

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Schematic illustration of the synthetic process for hollow spheres.
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fig02: Schematic illustration of the synthetic process for hollow spheres.

Mentions: My original goal in this dissertation was to present a facile, environmentally benign, economically sustainable, and additive-free synthetic protocol for the fabrication of hollow oxides, which could ultimately enable the fine-tuning of hollow inorganic materials. The synthesis was achieved via a facile one-pot hydrothermal strategy with the use of simple sugars (glucose or fructose) as sacrificial templates (Scheme 1).


Facile Hydrothermal Fabrication of Nano-Oxide Hollow Spheres using Monosaccharides as Sacrificial Templates.

Abdelaal HM - ChemistryOpen (2014)

Schematic illustration of the synthetic process for hollow spheres.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4380956&req=5

fig02: Schematic illustration of the synthetic process for hollow spheres.
Mentions: My original goal in this dissertation was to present a facile, environmentally benign, economically sustainable, and additive-free synthetic protocol for the fabrication of hollow oxides, which could ultimately enable the fine-tuning of hollow inorganic materials. The synthesis was achieved via a facile one-pot hydrothermal strategy with the use of simple sugars (glucose or fructose) as sacrificial templates (Scheme 1).

View Article: PubMed Central - PubMed

Affiliation: Ceramics Department, The National Research Centre Al-Buhouth St. Dokki, Cairo (Egypt).

AUTOMATICALLY GENERATED EXCERPT
Please rate it.

The synthesis was achieved via a facile one-pot hydrothermal strategy with the use of simple sugars (glucose or fructose) as sacrificial templates (Scheme 1)... More precisely, the synthesis of glucose- and fructose-derived carbonaceous spheres via hydrothermal hydrolysis in a closed system (100 mL Teflon-lined stainless steel autoclave) was investigated... Shrinkage occurs after thermal treatment of C@SiO2 precursor composites at 550 °C for 5 h; the size decreases by approximately 65 to 80 %... In addition, it was found that PHSNPs vary between approximately 25 and 50 nm in diameter as shown in TEM images... The removal of the interior carbonaceous cores via heat treatment through oxidation in air yields free-standing hollow crystalline oxide spheres... Ball-in-ball (bnb) hollow structures were found within the final products without any further synthetic steps (Scheme 3)... We believe that the key to success in fabricating hollow metal oxide spheres, using glucose or fructose as sacrificial templates, is the fact that their derived carbonaceous sphere surface is rich in oxygen functionalities (e.g. OH and C=O)... The last part of the thesis concerns similarities and differences between glucose and fructose as sacrificial templates for the fabrication of the inorganic oxide hollow spheres... In this part, significant differences between fructose and glucose templates were observed... Applying fructose as a template allows for a lower reaction temperature and shorter reaction time compared with the reaction using glucose... Overall, this work shows that using simple sugars as sacrificial templates in a one-pot hydrothermal method is an efficient means of fabricating micro- and nano-sized oxides with hollow structures... We have applied fructose as a new sacrificial template for fabricating Cr2O3, α-Fe2O3, Co3O4, NiO, and ZnO with hollow structures for the first time, to the best of our knowledge... Glucose has also been successfully used for fabricating the same hollow-sphere oxides... Important factors critical to fine-tune the final particle size and shape are temperature, reaction time, and the addition of acetic acid as a catalyst... Lastly, we have shown that the most significant difference between the two monosaccharides is the decrease in reaction time and energy when applying fructose as the sacrificial template.

No MeSH data available.