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parent mesostructured materials by exchanging the surfactant without the collapse of
the mesostructure. The BET surface area of the mesoporous hybrid could reach up
to 793 cm
2
g
−
1
, accompanied with a narrow pore width distribution around 2.7 nm.
This procedure was on the basis of the use of C
16
TABr as a structure-directing
agent and 2,2′,2″-nitrilotriethanol as the complexing polyalcohol, which had proven
its capability in controlling the rates of hydrolytic reactions of aluminum species
in water-phosphoric acid media and the subsequent process of self-assembly in
the presence of surfactant aggregates [
51
]. The hybrid nature of the pore wall can
be modulated continuously from organic-free mesoporous aluminum phosphates
(ALPOs) up to total incorporation of organophosphorus entities (mesoporous phos-
phonates and diphosphonates). The organic functional groups become basically
attached to the pore surface or inserted into the ALPO framework (homogeneously
distributed along the surface and inner pore walls) depending on the use of phospho-
nic or diphosphonic acids, respectively.
The successful preparation of periodic mesoporous titanium phosphonate
(PMTP-1) with bridged organic linkers inside the framework was achieved by
Ma et al. [
52
] via an autoclaving process followed by an evaporation-induced
self-assembly (EISA) strategy (Fig.
3.9
). To slow down the hydrolysis of tita-
nium tetrachloride, the metallic precursors were dissolved in the ethanol pre-
viously to form TiOCH
2
CH
3
complexes [
53
,
54
]. A cryosel bath was used to
create low-temperature conditions as well to reduce the condensation speeds of
the reactants. This could avert the generation of large titania or titanium phos-
phonate aggregations during the reaction process. The highly ordered mesostruc-
tures were obtained when a moderately acidic pH value was sustained, according
to the (S
0
H
+
)X
−
I
+
mechanism. This was probably due to the newly formed gel
being partially damaged in the strong acid system and that alkaline conditions
led to a fast hydrolysis rate. The surface area, pore size, and pore volume were
1,066 m
2
g
−
1
, 2.8 nm, and 0.83 cm
3
g
−
1
, respectively. This mechanism could
be extensively applied to the formation of a series of periodic mesoporous metal
phosphate and phosphonate materials with different structural phases in the pres-
ence of nonionic surfactants in acidic media [
55
,
56
].
Ionic liquids (ILs), considered as tunable and environmentally friendly
solvents, have attracted a lot of interest in the synthesis of novel materials. Zhang
et al. [
57
] synthesized well-ordered mesoporous MOF nanospheres constructed
by a microporous framework in a system of ILs-surfactant combined with super-
ficial CO
2
(Fig.
3.10
). The IL and surfactant chosen were 1,1,3,3-tetramethyl-
guanidinium acetate (TMGA) and
N
-ethyl perfluorooctylsulfonamide (EtFOSA),
respectively. It has been shown that TMGA/EtFOSA/CO
2
microemulsions could
be formed [
58
]. The surfactant molecules self-assembled into cylindrical micelles
with the fluorocarbon chain directed toward the inside of the micelles, and CO
2
existed as a core of the micelles. Thereafter, the Zn(II) ions and 1,4-benzenedicar-
boxylic acid linked facilely around the formed micelles. Thus, the mesoporosity
was generated from the templating effect of the surfactants, and the microporos-
ity was related to the intracrystalline cavities. The calculated sizes of mesopores
and micropores were 3.6 and 0.7 nm, respectively, as well as a total surface area
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