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
Bi5FeTi3O15 Hierarchical Microflowers: Hydrothermal Synthesis, Growth Mechanism, and Associated Visible-Light-Driven Photocatalysis
TL;DR: Nanostructured Bi5FeTi3O15 prepared by a facile hydrothermal method is reported as a new visible-light-driven photocatalyst, which exhibits a nanoplates-built, flower-like hierarchical structure.
Journal ArticleDOI
Hydrothermal Treatment of Nanoparticle Thin Films for Enhanced Mechanical Durability
TL;DR: T Tribochemical wear was found to planarize the nanoscale surface texture of these films, similar to what is observed in chemo-mechanical polishing (CMP), useful for anyone trying to make robust superhydrophobic or superHydrophilic coatings.
Journal ArticleDOI
Recent advances in visible light-responsive titanium oxide-based photocatalysts
TL;DR: In this article, an overview of the recent advances achieved on visible light-responsive TiO2-based photocatalysts is presented, together with experimental physicochemical evidence to support the conclusions.
Journal ArticleDOI
Preparation, Characterisation, and Photocatalytic Behaviour of Co-TiO2 with Visible Light Response
Rossano Amadelli,Luca Samiolo,Andrea Maldotti,Alessandra Molinari,Mario Valigi,Delia Gazzoli +5 more
TL;DR: The influence of cobalt addition on the performance of T i O 2 as a photocatalyst in the degradation of 4-chlorophenol and Bisphenol A is investigated in this article.
Journal ArticleDOI
A simple combustion method for the synthesis of multi-functional ZrO2/CuO nanocomposites: Excellent performance as Sunlight photocatalysts and enhanced latent fingerprint detection
L. Renuka,K.S. Anantharaju,Y.S. Vidya,H.P. Nagaswarupa,S.C. Prashantha,S.C. Sharma,H. Nagabhushana,G.P. Darshan +7 more
TL;DR: A facile solution combustion synthesis has been adopted to synthesize ZrO2/CuO nanocomposite oxides (NCO) by utilizing Oxalyl dihydrazide (ODH) as fuel as mentioned in this paper.
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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