Rutile Crystallites Isolated from Degussa (Evonik)
P25 TiO<sub>2</sub>: Highly Efficient Photocatalyst for Chemoselective
Hydrogenation of Nitroaromatics
Yasuhiro Shiraishi
Hiroaki Hirakawa
Yoshiki Togawa
Yoshitsune Sugano
Satoshi Ichikawa
Takayuki Hirai
10.1021/cs400532p.s001
https://acs.figshare.com/articles/journal_contribution/Rutile_Crystallites_Isolated_from_Degussa_Evonik_P25_TiO_sub_2_sub_Highly_Efficient_Photocatalyst_for_Chemoselective_Hydrogenation_of_Nitroaromatics/2369944
We
report that the rutile crystallites, isolated from Degussa (Evonik)
P25 TiO<sub>2</sub> by a hydrofluoric acid treatment, behave as a
highly efficient photocatalyst for hydrogenation of nitroaromatics.
Photoirradiation (λ >300 nm) of the isolated rutile particles
with alcohol as a hydrogen source successfully promotes chemoselective
hydrogenation of nitroaromatics to anilines, with an activity higher
than that of commercially available rutile TiO<sub>2</sub>. The high
activity of the isolated rutile particles is due to the specific distribution
of structural defects (oxygen vacancy sites) on the particles. These
particles contain a relatively small number of inner defects behaving
as recombination centers for photoformed electron (e<sup>–</sup>) and positive hole (h<sup>+</sup>) pairs, and a relatively large
number of surface defects behaving as reduction sites for nitroaromatics.
Photoexcitation of the isolated particles therefore promotes efficient
charge separation between e<sup>–</sup> and h<sup>+</sup>,
and facilitates rapid reduction of nitroaromatics adsorbed on the
surface defects. This thus results in very high hydrogenation activity
on the rutile particles isolated from P25 TiO<sub>2</sub>.
2016-02-18 17:58:36
hydrofluoric acid treatment
rutile TiO 2.
hydrogenation
surface defects
P 25 TiO 2
nitroaromatic
rutile particles
oxygen vacancy sites