5.51 The Case of Shape-Controlled SnO 2
In analogy with the case of TiO 2 , while aiming at a different functionality, SnO 2
shape-controlled nanocrystals have been studied as for their sensing properties [26].
Octahedral (OCT), elongated dodecahedral (DOD), and nanobar (NBA)
nanocrystals were evaluated in sensing toward CO (Fig. 5.39).
The abundance of singly ionized oxygen vacancies V 0
þ , ESR active, was associated with the exposed crystal faces and in turn to the sensing response. Results indicate
that the electrical properties and the formation of V 0 centers are interconnected.
5.52 Discussion of the Case
5.52.1 Shape and Structure
Figure 5.40 reports the shapes of nanobar and dodecahedral particles to describe as
the data can be read.
For OCT nanoparticles, Fig. 5.41 describes structure and orientations.
5.52.2 Identification of Defects
In order to study how the exposition of specific crystal faces affects the reactivity of
the nanocrystals with different shapes, as concerns the reactivity of the species V 0
þ
O
− O
2− O 2
− involved in the sensing mechanism, a comprehensive ESR investigation of OCT, DOD, and NBA was carried out (Fig. 5.42).
Fig. 5.39 Shapes, defects, and electric responses in SnO 2 nanoparticles [26]
134
5 The Symmetry Properties Describe the Electronic Structure …
In analogy with the case of TiO 2 , while aiming at a different functionality, SnO 2
shape-controlled nanocrystals have been studied as for their sensing properties [26].
Octahedral (OCT), elongated dodecahedral (DOD), and nanobar (NBA)
nanocrystals were evaluated in sensing toward CO (Fig. 5.39).
The abundance of singly ionized oxygen vacancies V 0
þ , ESR active, was associated with the exposed crystal faces and in turn to the sensing response. Results indicate
that the electrical properties and the formation of V 0 centers are interconnected.
5.52 Discussion of the Case
5.52.1 Shape and Structure
Figure 5.40 reports the shapes of nanobar and dodecahedral particles to describe as
the data can be read.
For OCT nanoparticles, Fig. 5.41 describes structure and orientations.
5.52.2 Identification of Defects
In order to study how the exposition of specific crystal faces affects the reactivity of
the nanocrystals with different shapes, as concerns the reactivity of the species V 0
þ
O
− O
2− O 2
− involved in the sensing mechanism, a comprehensive ESR investigation of OCT, DOD, and NBA was carried out (Fig. 5.42).
Fig. 5.39 Shapes, defects, and electric responses in SnO 2 nanoparticles [26]
134
5 The Symmetry Properties Describe the Electronic Structure …