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thus drawing wide attention. A modified Stöber method combined with surfactant
self-assembly is usually adopted to prepare mesoporous silica microspheres. Instead
of employing typical emulsion-templating methods with nonpolar solvents such as
trimethylbenzene, a self-templating emulsion route was developed for the formation
of a spherically shaped hollow manganese phosphonate-based hybrid with hierar-
chically porous shells [
1
]. Drops of liquid organophosphonic claw molecules added
to a manganese chloride solution did not disappear immediately but, in contrast,
the drops broke up into many smaller nanosized spheres under mild stirring, and
an emulsion-like solution was thus generated. The phosphonic droplets became cov-
ered with the subsequently growing layers of the manganese phosphonates, which
could preserve the initial shape of the nanodrops. Upon heating under hydrother-
mal conditions, a portion of phosphonic droplets gradually defused out through the
formed phosphonate shell to react with the remaining inorganic metal precursors in
the mixed solution, and this process was similar to the Kirkendall effect [
2
]. The
continuous supply of phosphonic acid and metal ions exerted a thermodynamic
control over the condensation between the inorganic units and the organic moieties.
Correspondingly, hollow manganese phosphonate microspheres possessing meso-
cellular foam structures close to the internal shell and secondary smaller mesostruc-
tured pores approaching the surface layers were formed. The progress that resulted
in the formation of phosphonate hybrid microspheres is reminiscent of the interfa-
cial emulsion polymerization technique that has been developed for the nanoscaled
silver hollow sphere (using n-dodecane/water emulsion) and silica (using an oil/
water emulsion) hollow nanosphere synthesis [
3
,
4
]. The average diameter of these
hybrid microspheres is approximately 0.5-2 mm (Fig.
4.1
). The shell thickness is
about 150 nm, which results from the aggregation of nanospherical particles with
diameters of 5-35 nm. A novel mesocellular foam structure, akin to mesostruc-
tured cellular foam (MCF), can be seen. Secondary mesostructured pores of several
nanometers emerge near the inferior pore surface layers.
More recently, on the basis of the water-soluble but ethanol-insoluble properties
of DTPMP, we developed a template-free strategy to synthesis organic-inorganic
hybrid of cobalt phosphonate hollow nanostructured spheres, exhibiting high effi-
ciency in oxidizing degradation of organic contaminants in the presence of perox-
ymonosulphate. A facile phosphate-mediated self-assembly methodology has been
carried out to prepare mesoporous nickel phosphate/phosphonate hybrid micro-
spheres, showing surface area of 267 m
2
g
−
1
and total pore volume of 0.191 cm
3
g
−
1
[
5
]. It could be considered that drops of liquid organophosphonic claw molecules
added to a manganese chloride solution did not disappear immediately but, in con-
trast, the drops broke up into many smaller nanosized spheres under mild stirring,
and an emulsion-like solution was thus generated. The phosphonic droplets became
covered with the subsequently growing layers of the manganese phosphonates,
which could preserve the initial shape of the nanodrops. Upon heating under hydro-
thermal conditions, a portion of phosphonic droplets gradually defused out through
the formed phosphonate shell to react with the remaining inorganic metal precur-
sors in the mixed solution. The continuous supply of phosphonic acid and metal
ions exerted a thermodynamic control over the condensation between the inorganic
units and the organic moieties. Correspondingly, hollow manganese phosphonate
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