Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Photocatalytic Behavior of Fluorinated Rutile TiO$_2$(110) Surface:
  Understanding from the Band Model   Surface fluorination of TiO$_2$ (F-TiO$_2$) has complicate photocatalytic
behavior in degradation of organic compounds. This work attempts to establish
an elegant scenario based on the band model to understand this behavior.
Density functional theory (DFT) calculations show that fluorination of the
rutile TiO$_2$(110) surface (F-TiO$_2$${110}$) results in the falling of band
edges. The falling of valence band edge (VBE) facilitates production of free
$\cdot$OH radicals, whereas the falling of conduction band edge (CBE) lowers
the reducing power of photo-electrons and inhibits reductive reactions mediated
by them. As a result, the photo-electrons are built up in the conduction band
which depresses photo-holes in the valence band to produce $\cdot$OH radicals
due to the requirement of electrical neutrality and thus leads to a low
degradation rate of organic compounds. Even though, our model suggests a route
to improve the degradation efficiency, by introducing a scavenger of
photo-electrons to promote formation of $\cdot$OH radicals.

32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
15
The categories of this paper are: nucl-ex
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an