Journal ArticleDOI
The Role of Metal Ion Dopants in Quantum-Sized TiO2: Correlation between Photoreactivity and Charge Carrier Recombination Dynamics
TLDR
In this article, the presence of metal ion dopants in the TiO_2 crystalline matrix significantly influences photoreactivity, charge carrier recombination rates, and interfacial electron-transfer rates.Abstract:
A systematic study of metal ion doping in quantum (Q)-sized (2-4 nm) TiO_2 colloids is performed by measuring their photoreactivities and the transient charge carrier recombination dynamics. The presence of metal ion dopants in the TiO_2 crystalline matrix significantly influences photoreactivity, charge carrier recombination rates, and interfacial electron-transfer rates. The photoreactivities of 21 metal ion-doped colloids are quantified in terms of both the conduction band electron reduction of an electron acceptor (CCl_4 dechlorination) and the valence band hole oxidation of an electron donor (CHCl_3 degradation). Doping with Fe^(3+), Mo^(5+), Ru^(3+), Os^(3+), Re^(5+), V^(4+), and Rh^(3+) at 0.1-0.5 at.% significantly increases the photoreactivity for both oxidation and reduction while Co^(3+) and Al^(3+) doping decreases the photoreactivity. The transient absorption signals upon laser flash photolysis (λ_(ex) = 355 nm) at λ = 600 nm are extended up to 50 ms for Fe^(3+)-, V^(4+)-, Mo^(5+)-, and Ru^(3+)-doped TiO_2 while the undoped Q-sized TiO_2 shows a complete "blue electron" signal decay within 200 μs. Co^(3+)- and Al^(3+)-doped TiO_2 are characterized by rapid signal decays with a complete loss of absorption signals within 5 μs. The quantum yields obtained during CW photolyses are quantitatively correlated with the measured transient absorption signals of the charge carriers. Photoreactivities
are shown to increase with the relative concentration of trapped charge carriers. The photoreactivity of doped TiO_2 appears to be a complex function of the dopant concentration, the energy level of dopants within the TiO_2 lattice, their d electronic configuration, the distribution of dopants, the electron donor concentration, and the light intensity.read more
Citations
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Journal ArticleDOI
Electronic properties of rutile TiO2 doped with 4d transition metals: First-principles study
TL;DR: In this paper, the effect of doping on rutile TiO 2 was studied using the first principles method in the framework of the density functional theory, and the results showed that Y, Ag and Cd are p-type dopants, while Nb and Mo are n-type ones, while Tc, Ru, Rh or Pd induces intermediate bands to divide the forbidden gap of the host phase into sub-gaps.
Journal ArticleDOI
Generalized Synthetic Strategy for Transition-Metal-Doped Brookite-Phase TiO2 Nanorods.
Zhiyong Zhang,Qiyuan Wu,Grayson Johnson,Yifan Ye,Xing Li,Na Li,Meiyang Cui,Jennifer D. Lee,Chang Liu,Shen Zhao,Shuang Li,Alexander Orlov,Christopher B. Murray,Xu Zhang,T. Brent Gunnoe,Dong Su,Sen Zhang +16 more
TL;DR: A generalized wet-chemical methodology for the synthesis of transition metal (M) doped brookite-phase TiO2 nanorods (NRs) with unprecedented wide-range tunability in dopant composition, allowing tuning of dopant-dependent properties of TiO 2 nanomaterials for new opportunities in catalysis applications.
Journal ArticleDOI
Enhanced photocatalytic activities of TiO2 nanocomposites doped with water-soluble mercapto-capped CdTe quantum dots
Yue-Sheng Li,Feng-Lei Jiang,Qi Xiao,Ran Li,Kan Li,Mei-Fang Zhang,Ai-Qing Zhang,Shao-Fa Sun,Yi Liu +8 more
TL;DR: In this article, the photocatalytic activity of CdTe quantum dots (QDs)-doped TiO2 was investigated by degrading malachite green (MG) in aqueous solution under halogen-tungsten lamp irradiation.
Journal ArticleDOI
Photoelectrocatalytic degradation of quinoline with a novel three-dimensional electrode-packed bed photocatalytic reactor
TL;DR: In this paper, the performance of photo-catalytic degradation of quinoline in saline water was evaluated with a newly designed continuous flow three-dimensional electrode-packed bed photocatalytic reactor.
Journal ArticleDOI
Sonophotocatalytic treatment of Naphthol Blue Black dye and real textile wastewater using synthesized Fe doped TiO2
TL;DR: In this paper, the treatment of Naphthol-Blue-Black (NBB) dye and real textile wastewater through sonophotocatalytic technique was examined and the effect of pH, gas content (Ar, O 2, air and N 2 ), H 2 O 2 concentration and catalyst loading were examined.
References
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Book
Inorganic Chemistry: Principles of Structure and Reactivity
TL;DR: In this article, inorganic chemistry principles of structure and reactivity are presented. But, they do not cover how to use these principles in the design of products, and they are not available in any type of product.
Book
Transition Metal Oxides: An Introduction to Their Electronic Structure and Properties
TL;DR: In this article, the authors present a chemical aspects structural principles of electronic classification and models of electronic structure: ionic models cluster models band theory intermediate models, point-defects and semiconduction, electronic carrier properties.
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