Kelvin probe force microscopy of nanocrystalline TiO₂ photoelectrodes

• Alex Henning,
• Gino Günzburger,
• Res Jöhr,
• Yossi Rosenwaks,
• Biljana Bozic-Weber,
• Catherine E. Housecroft,
• Edwin C. Constable,
• Ernst Meyer and
• Thilo Glatzel

Beilstein J. Nanotechnol. 2013, 4, 418–428, doi:10.3762/bjnano.4.49

• investigations [39][40]. KPFM studies in UHV conditions of rutile TiO2 decorated with either nanometer-sized Pt clusters [41] or single dye molecules [42] revealed a significant impact of single particles on the surface dipole. We have investigated the surface parameters of DSC photoelectrodes on the nanoscale

• rutile TiO2 in ultrahigh vacuum [42]. Using Equation 4 with θ = 0° and measured work-function shifts of ΔΦ = −180 ± 40 mV for the Cu(I) dye and ΔΦ = 150 ± 40 mV for N719 results in 6.3 ± 1.5 D and 5.3 ± 2 D with opposite directions, respectively. The latter value is in the same range as predicted by DFT

Photocatalytic antibacterial performance of TiO₂ and Ag-doped TiO₂ against S. aureus. P. aeruginosa and E. coli

• Kiran Gupta,
• R. P. Singh,
• Ashutosh Pandey and
• Anjana Pandey

Beilstein J. Nanotechnol. 2013, 4, 345–351, doi:10.3762/bjnano.4.40

• that the annealed sample of TiO2 has both anatase and rutile phases while only an anatase phase was found in Ag-doped TiO2 nanoparticles. The decreased band-gap energy of Ag-doped TiO2 nanoparticles in comparison to TiO2 nanoparticles was investigated by UV–vis spectroscopy. The rate of recombination

• microorganisms including bacteria, fungi and viruses, because it has high photoreactivity, broad-spectrum antibiosis and chemical stability [1][2][3][4][5][6]. The photocatalytic activity of annealed TiO2 sturdily depends upon its existing phase, i.e., anatase, rutile, brokite. The anatase phase shows an

• indirect optical band gap of 3.2 eV, while the rutile phase has a direct band gap of 3.06 eV and an indirect one of 3.10 eV [7]. However, crude nanoparticles are amorphous in nature, with decreased surface area, and show a fast recombination rate of electrons and holes. Finally the antibacterial activity

Near-field effects and energy transfer in hybrid metal-oxide nanostructures

• Ulrich Herr,
• Barat Achinuq,
• Cahit Benel,
• Giorgos Papageorgiou,
• Manuel Goncalves,
• Johannes Boneberg,
• Paul Leiderer,
• Paul Ziemann,
• Peter Marek and
• Horst Hahn

Beilstein J. Nanotechnol. 2013, 4, 306–317, doi:10.3762/bjnano.4.34

• , whereas for higher Eu concentrations an increasing fraction of rutile is visible. Optical properties of the materials were determined by photoluminescence spectroscopy in a Fluorolog FL3-22 spectrometer (Jobin Yvon) equipped with a Hamamatsu R928P photomultiplier tube. Excitation and emission spectra were

• TiO2:Eu nanophosphors produced by the CVR method. For low Eu concentrations, only the anatase phase is found, whereas for higher concentrations a mixture of anatase and rutile can be observed. Normalized emission spectra of Eu3+ in TiO2 under excitation at 330 or 390 nm. Excitation spectrum of TiO2:Eu

Mesoporous MgTa₂O₆ thin films with enhanced photocatalytic activity: On the interplay between crystallinity and mesostructure

• Jin-Ming Wu,
• Igor Djerdj,
• Till von Graberg and
• Bernd M. Smarsly

Beilstein J. Nanotechnol. 2012, 3, 123–133, doi:10.3762/bjnano.3.13

• Supporting Information File 1. Both the mesoporous and the nonporous (nontemplated) films show distinct X-ray diffraction (XRD) reflections corresponding to a tri-rutile structure MgTa2O6 (JCPDS card 32-0631), only after calcination at temperatures beyond 760 °C, as illustrated in Figure 1. The crystallinity

• homogeneously. After calcination, the F127-templated MgTa2O6 film exhibited XRD patterns corresponding to tri-rutile structure MgTa2O6 (see Figure S1 for the 2-D-SAXS patterns, Figure S2 for the SEM morphology, and Figure S3 for the XRD pattern in Supporting Information File 1). From Figure 8b it can be seen

Self-assembled monolayers and titanium dioxide: From surface patterning to potential applications

• Yaron Paz

Beilstein J. Nanotechnol. 2011, 2, 845–861, doi:10.3762/bjnano.2.94

• grafting density with respect to chemisorption by conventional methods (2.8–3.0 molecules per nm2 versus 4.3–4.8 molecules per nm2). It is worth mentioning that a study on organosilane monolayers formed on the surfaces of zirconia and titania (anatase and rutile), by a gas–phase process employing

Nanostructured, mesoporous Au/TiO₂ model catalysts – structure, stability and catalytic properties

• Matthias Roos,
• Dominique Böcking,
• Kwabena Offeh Gyimah,
• Gabriela Kucerova,
• Joachim Bansmann,
• Johannes Biskupek,
• Ute Kaiser,
• Nicola Hüsing and
• R. Jürgen Behm

Beilstein J. Nanotechnol. 2011, 2, 593–606, doi:10.3762/bjnano.2.63

• formation of the thermodynamically stable polymorph rutile, with complete transformation from anatase to rutile at about 1000 °C (cf. Figure 3). Concomitantly with crystallization, the organized mesopore system collapsed during the heat treatment as expected when structure-directing agents, such as Pluronic

Schottky junction/ohmic contact behavior of a nanoporous TiO₂ thin film photoanode in contact with redox electrolyte solutions

• Masao Kaneko,
• Hirohito Ueno and
• Junichi Nemoto

Beilstein J. Nanotechnol. 2011, 2, 127–134, doi:10.3762/bjnano.2.15

• order to investigate further the behavior in Figure 7, larger size (500 nm) TiO2 (G2, rutile >95%, note that anatase-rich sample is not available and difficult to prepare for this particle size) was used instead of the Ti-nanoxide T/SP (average diameter 13 nm, anatase >90%), and the CVs at the

• To prepare a nanoporous TiO2 film, Ti-nanoxide paste (T/SP, average particle size 13 nm, anatase >90%) was purchased from Solaronix SA, Aubonne, Switzerland. Larger size TiO2 powders, G2 (500 nm, rutile >95%) was purchased from Showa Denko Co., Ltd, Japan. F-doped SnO2 conductive glass (FTO, surface