The surfactant molecule (P123) can self-assemble into a
lyotropic liquid-crystalline phase in an acidic solution. TiCl4, which
was added in the preparation system, functions as the pH “adjustor,”
the hydrolysis-condensation “controller,” and as a titanium
source. On the other hand, TTIP was used as a titanium source
only. Graphene oxide was obtained by peeling off graphite oxide
using a 500 W ultrasonic crasher. When the mixture of P123 and
the precursors (TTIP/TiCl4 and graphene oxide) in an EtOH/H2O
medium was stirred at room temperature, the precursors were
initially uniformly dispersed in the gap of the lyotropic liquidcrystalline
phase. A graphene oxide/Ti(Oi–Pr)4−xTiCl4−y(OH2
+)x+y
framework was formed because of the incomplete hydrolysis and
condensation of TTIP/TiCl4 in an acidic condition. The framework
then interacted with P123 to form a semitransparent sol of
the graphene oxide/Ti(Oi–Pr)4−xTiCl4−y(OH2
+)x+y–EO20PO70EO20
inorganic–organic framework through hydrogen bonding. This
sol was subjected to solvothermal treatment at 150 ◦C and then
slowly dehydrated. After these two steps, graphene oxide was
reduced to graphene via the solvothermal treatment, and the
inorganic precursors were further hydrolyzed and crosslinked
to yield a graphene/(OH)4−nTi(OTi)n–EO20PO70EO20 framework.
This framework was reinforced via low-temperature thermal
treatment (100 ◦C). After hot ethanol extraction, the template
can be easily removed, which produced graphene/TiO2 composites
with TiO2 nano-particles that are uniformly dispersed
on single-layer graphene nano-sheets and with a large surface
area (Table 1 and Fig. 2). Moreover, the powders had
an imperfect anatase crystal phase with a small amount of a
brookite phase,