How to prepare highly active MgO nanoparticles?

The preparation of highly active MgO nanoparticles can be achieved through various methods,including precipitation method,calcination method,ultrasonic method,and innovative one-step method.

The preparation of highly active MgO nanoparticles can be achieved through various methods,including precipitation method,calcination method,ultrasonic method,and innovative one-step method.The following will provide a detailed introduction to these methods:

Precipitation method

Preparation of precursor:Magnesium hydroxide(Mg(OH)2)precursor is prepared by direct precipitation method in liquid-phase synthesis process.Dissolve magnesium chloride(MgCl2)in anhydrous ethanol,add organic dispersant ethylene glycol,stir and mix evenly.Then slowly add sodium hydroxide(NaOH)solution dropwise,continue stirring and let it stand for aging to obtain white Mg(OH)2 precursor.

Concentration adjustment:The appropriate concentration of reactants has a significant impact on the morphology of the product.When the concentration of NaOH is 0.5 mol/L,sheet-like Mg(OH)2 precursor can be obtained,which has good crystallization and dispersion.

Calcination method

Heat treatment procedure:The prepared Mg(OH)2 precursor is calcined to obtain white cubic nano MgO solid.During the calcination process,MgO nanoparticles with excellent properties can be obtained by controlling the temperature and time.

Performance characterization:X-ray diffraction(XRD)and scanning electron microscopy(SEM)were used to characterize the structure and analyze the morphology of the sample.The obtained MgO nanoparticles typically exhibit good crystallinity and uniform morphology.

Ultrasonic method

Ultrasonic treatment:Using ultrasonic waves to continuously compress and stretch liquid molecules,creating alternating positive and negative pressure zones,causing water molecules to exhibit alternating density changes,resulting in microbubbles in sparse areas and growing in negative pressure zones.When microbubbles rupture,the surrounding water phase quickly rushes towards the center of the bubble,releasing a strong pressure pulse.The pressure of this pulse is often higher than 104 KPa,and this phenomenon is also known as ultrasonic cavitation effect.This method utilizes the mechanism of ultrasonic cavitation,which causes a large number of microbubbles to be generated as the liquid phase continuously expands and compresses.The microbubbles continuously generate shock waves in the positive pressure zone to strike the surface of the material,causing the layered magnesium oxide to be peeled off layer by layer,thereby generating magnesium oxide nanosheets.

Innovative one-step approach

Thermal decomposition synthesis:MgO nanoparticles are obtained by thermal decomposition of nanoscale Mg(OH)2.This method is innovative,time-saving,cost-effective,scalable,and patented.The obtained MgO nanoparticles are roughly spherical,monodisperse,and single crystalline,with a size of≤10nm and a surface area of up to 178 m²/g,exhibiting a bimodal mesoporous distribution.

Composite modification method

Solid phase synthesis:MgO nanoparticles prepared by ultrasonic hydrolysis method are mixed withα-Fe2O3 nanoparticles prepared by chemical precipitation method.After ultrasonic activation and solid-phase synthesis,MgFe2O4 nanoparticles are prepared.The ultrasonic cavitation effect enhances the activity of chemical reactions,promotes the speed of solid-phase synthesis reactions,and achieves chemical reactions that are difficult to complete under general conditions.

In summary,the preparation of highly active MgO nanoparticles requires comprehensive consideration of various factors such as material synthesis methods,condition optimization,and subsequent processing.These strategies work together and effectively enhance the potential applications of MgO nanoparticles in catalysis,adsorption,and biomedical fields.