nanocrystals were achieved by in situ growth on the 3D-structured graphene
(Fig. 5.14b).
As we mentioned above, most of the reported graphene aerogels and hydrogels
are very fragile, which is difficult to undergo the stirring treatment during the
photocatalysis process. Thus, the mechanical strength is another important characteristic for the TiO 2 /graphene aerogels or hydrogels. In order to promote the
mechanical strength of graphene hydrogels, Cong et al. [63] used the polyacrylamide
Fig. 5.13 (a) Low-magnified SEM images of freeze-dried TGH; inset of (a) is the photograph of
TGH with different ratios of TiO 2 to graphene at 180
C for 2 h. (b) Low-magnified TEM images of
freeze-dried TGH. (c) XRD patterns of TGH, GH, and GO; C1s XPS spectra of hydrogels before (d)
and after (e) TiO 2 loading. (Reprinted with permission from Ref. [65]. Copyright 2013, American
Chemical Society)
Fig. 5.14 (a) FTIR spectra for GAs with and without TiO 2 nanocrystals (67 wt% TiO 2 on GAs);
(b) TEM image for the TiO 2 /GAs composite. (Reprinted with permission from Ref. [66]. Copyright
2014, American Chemical Society)
5.2 TiO 2 /Graphene Composite
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