A nanometric cushion for enhancing scratch and wear resistance of hard films

• Katya Gotlib-Vainshtein,
• Olga Girshevitz,
• Chaim N. Sukenik,
• David Barlam and
• Sidney R. Cohen

Beilstein J. Nanotechnol. 2014, 5, 1005–1015, doi:10.3762/bjnano.5.114

• control the scratch resistance of oxide surfaces. Titania films of several nm thickness are coated onto substrates of silicon, kapton, polycarbonate, and polydimethylsiloxane (PDMS). The scratch resistance measured by scanning force microscopy is found to be substrate dependent, diminishing in the order

• PDMS, kapton/polycarbonate, Si/SiO2. Furthermore, when PDMS is applied as an intermediate layer between a harder substrate and titania, marked improvement in the scratch resistance is achieved. This is shown by quantitative wear tests for silicon or kapton, by coating these substrates with PDMS which

• is subsequently capped by a titania layer, resulting in enhanced scratch/wear resistance. The physical basis of this effect is explored by means of Finite Element Analysis, and we suggest a model for friction reduction based on the "cushioning effect” of a soft intermediate layer. Keywords: finite

Nanostructure sensitization of transition metal oxides for visible-light photocatalysis

• Hongjun Chen and
• Lianzhou Wang

Beilstein J. Nanotechnol. 2014, 5, 696–710, doi:10.3762/bjnano.5.82

• several experimental and theoretical researches. For instance, Du et al. used ab initio calculations to demonstrate that a graphene/titania interface in the ground electronic state forms a charge-transfer complex due to the large difference of work functions between graphene and TiO2 [99]. Most

Extracellular biosynthesis of gadolinium oxide (Gd₂O₃) nanoparticles, their biodistribution and bioconjugation with the chemically modified anticancer drug taxol

• Shadab Ali Khan,
• Sanjay Gambhir and
• Absar Ahmad

Beilstein J. Nanotechnol. 2014, 5, 249–257, doi:10.3762/bjnano.5.27

• high temperatures, and employ harsh environments, thus rendering it difficult to find any usage of Gd2O3 nanoparticles in biomedical applications. Our group has already reported the biological synthesis of zirconia, titania, silica and CuAlO2 nanoparticles [12][13][14]. In this work, we employed a

Modeling and optimization of atomic layer deposition processes on vertically aligned carbon nanotubes

• Nuri Yazdani,
• Vipin Chawla,
• Eve Edwards,
• Vanessa Wood,
• Hyung Gyu Park and
• Ivo Utke

Beilstein J. Nanotechnol. 2014, 5, 234–244, doi:10.3762/bjnano.5.25

• guidelines; titania, TiO2; Introduction Recent advances in the synthesis and processing of carbon nanotubes (CNTs) have enabled the prospect of their integration into existing technologies that exploit the high surface area of mesoporous ceramic films [1]. Over the last 10 years, ceramic coated CNTs have

Study of mesoporous CdS-quantum-dot-sensitized TiO₂ films by using X-ray photoelectron spectroscopy and AFM

• Mohamed N. Ghazzal,
• Robert Wojcieszak,
• Gijo Raj and
• Eric M. Gaigneaux

Beilstein J. Nanotechnol. 2014, 5, 68–76, doi:10.3762/bjnano.5.6

• titania films (degradation of the template agent and inorganic network consolidation) were then obtained by calcination in air at 400 °C over 2 h with a rising step of 1 °C min−1. Preparation of QDs-CdS-sensitized TiO2 QDs-CdS were prepared following the procedure previously described by Besson et al. [9

• ]. Briefly, the titania films were dipped for 1 min into a saturated nitrate solution of Cd2+ and washed with water for several times in order to eliminate excess reactive species. The deposition of Cd2+ was performed under controlled pH (≈10), which was adjusted by adding NaOH solution at 1 M. The chemical

• . Similarly as described in [16], diffuse reflectance spectra of CdS/titania films were recorded by using an UV–vis spectrophotometer (Carry 5), which was equipped with an integrating sphere. The baseline was set by BaSO4 in the diffuse reflectance mode. The spectra were recorded at room temperature in the

Modulation of defect-mediated energy transfer from ZnO nanoparticles for the photocatalytic degradation of bilirubin

• Tanujjal Bora,
• Karthik K. Lakshman,
• Soumik Sarkar,
• Abhinandan Makhal,
• Samim Sardar,
• Samir K. Pal and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2013, 4, 714–725, doi:10.3762/bjnano.4.81

• molecular transformation of water-insoluble BR through photocatalysis is limited, a few studies are available on the photocatalytic degradation of BR adsorbed on nanostructured hydroxyapatite coatings [23] or molecularly imprinted titania films [24]. The current study focuses on the efficient utilization of

Characterization of electroforming-free titanium dioxide memristors

• John Paul Strachan,
• J. Joshua Yang,
• L. A. Montoro,
• C. A. Ospina,
• A. J. Ramirez,
• A. L. D. Kilcoyne,
• Gilberto Medeiros-Ribeiro and
• R. Stanley Williams

Beilstein J. Nanotechnol. 2013, 4, 467–473, doi:10.3762/bjnano.4.55

• single layer TiO2 (30 nm) was sputter-deposited from a titania source. For electroforming-free devices (described below), a bilayer was used consisting of TiO2−x (30 nm) and TiO2 (5 nm), where the thicker oxygen deficient layer was sputter deposited from a Ti4O7 Magnéli phase target and the thinner

• stoichiometric layer was again deposited from a stoichiometric titania target. Device junction areas studied included 1.5 × 1.5 μm2 and 3 × 3 μm2. The device area is defined by the overlap of the bottom and top electrode. X-ray diffraction (XRD) and selected area electron diffraction (SAED) showed that the

Nanostructure-directed chemical sensing: The IHSAB principle and the dynamics of acid/base-interface interaction

• James L. Gole and
• William Laminack

Beilstein J. Nanotechnol. 2013, 4, 20–31, doi:10.3762/bjnano.4.3

• are readily oxidized to SnOx (x = 2,4) and CuxO (x = 1,2) as demonstrated by XPS measurements [23]. The initially introduced titania (anatase) may be crystalline; however, we cannot be certain of this crystallinity after deposition to the PS interface. The untreated PS hybrid structures are exposed to

FTIR nanobiosensors for Escherichia coli detection

• Stefania Mura,
• Gianfranco Greppi,
• Maria Laura Marongiu,
• Pier Paolo Roggero,
• Sandeep P. Ravindranath,
• Lisa J. Mauer,
• Nicoletta Schibeci,
• Francesco Perria,
• Massimo Piccinini,
• Plinio Innocenzi and
• Joseph Irudayaraj

Beilstein J. Nanotechnol. 2012, 3, 485–492, doi:10.3762/bjnano.3.55

• necessary to improve the safety of our food supply chain. In this work we report on mesoporous titania thin-film substrates as sensors to detect E. coli O157:H7. Titania films treated with APTES ((3-aminopropyl)triethoxysilane) and GA (glutaraldehyde) were functionalized with specific antibodies and the

• ) oriented (one side polished and one side etched) were obtained from Jocam (Italy). Film preparation Titania (TiO2) thin films were prepared by dipping silicon wafers in a solution composed of TiCl4/Pluronic F127/H2O/EtOH (1:0.005:10:40) under controlled conditions of temperature and RH (relative humidity

• −1. The final calcination process to remove the organic template of these stabilized coatings was conducted at 350 °C for 3.5 h in air under static conditions at a heating rate of 10 °C·min−1. In this way mesoporous titania thin films were obtained and characterized as described in a previous work of

Variations in the structure and reactivity of thioester functionalized self-assembled monolayers and their use for controlled surface modification

• Inbal Aped,
• Yacov Mazuz and
• Chaim N. Sukenik

Beilstein J. Nanotechnol. 2012, 3, 213–220, doi:10.3762/bjnano.3.24

• the thioesters. The full exploitation of these systems in ways that take full advantage of the tunable wetting and that can extend the patterned titania deposition previously reported [16] will be the subject of future investigations. Trichlorosilyl thioesters. Thickness and contact angles (advancing

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

• monolayers may affect the photocatalytic properties of titania as well as be affected by these properties. Likewise, the superhydrophilicity of TiO2 known to be induced upon exposure to UV light [13] may affect the chemisorption process of SAMs. This gives rise to diverse phenomena, which can be utilized in

• therefore one could imagine that SAMs on titania may resemble SAMs on silica. This similarity is expected to be manifested primarily by the type of head groups that connect between the surface and the organic tails. Indeed, head groups such as chlorosilanes (RnSiCl4–n with n = 1,2,3), alkoxysilanes (RnSi(OR

• ')4–n with n = 1,2,3), carboxylic acids and isocyanates (–N=C=O) are common on both substrates. The fact that the Si–O bond length in silica (1.5–1.7 Å depending on the crystalline form) is similar to that of the Ti–O bond length in titania (1.9 Å) may suggest similar compactness. On the other hand

Template-assisted formation of microsized nanocrystalline CeO₂ tubes and their catalytic performance in the carboxylation of methanol

• Jörg J. Schneider,
• Meike Naumann,
• Christian Schäfer,
• Armin Brandner,
• Heiko J. Hofmann and
• Peter Claus

Beilstein J. Nanotechnol. 2011, 2, 776–784, doi:10.3762/bjnano.2.86

• ceria and other electron deficient metal oxides, such as zirconia [30][31] and titania [33], are active in direct carboxylation of methanol to DMC, they are also easily deactivated, sometimes already before recycling experiments can be started, resulting in only marginal methanol conversion. It can be

Approaches to nanostructure control and functionalizations of polymer@silica hybrid nanograss generated by biomimetic silica mineralization on a self-assembled polyamine layer

• Jian-Jun Yuan and
• Ren-Hua Jin

Beilstein J. Nanotechnol. 2011, 2, 760–773, doi:10.3762/bjnano.2.84

• exploited to functionalize the nanograss film with three representative species, namely porphyrin, Au nanoparticles and titania. Of particular note, the novel silica@titania composite nanograss surface demonstrated the ability to convert its wetting behavior between the extreme states (superhydrophobic

• –superhydrophilic) by surface hydrophobic treatment and UV irradiation. The anatase titania component in the nanograss film acts as a highly efficient photocatalyst for the decomposition of the low-surface-energy organic components attached to the nanosurface. The ease with which the nanostructure can be controlled

• (anatase titania). The silica@titania composite nanosurface exhibited an extreme change in photoresponsive wettability due to the presence of photocatalytic anatase titania, which can decompose hydrophobic organic components bonded to the surface. Results and Discussion The inner wall of a soda-lime glass

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

• (9.45 mmol) in 1.36 mL hydrochloric acid (conc.), resulting in a clear TiO2 sol. After an aging period of 60 min at room temperature, the sol was spin-coated on the precleaned Si substrates with a spinning speed of 4000 rpm (for 280 nm thickness) for 30 s. To vary the film thickness of the titania films

• calcination in air at 350 °C for 3 h, with a ramp rate of 1 K min−1. For the N2 sorption and inductively coupled plasma ionization spectroscopy (ICP–OES) measurements, a larger quantity of the titania material was needed: The remaining coating solution was cast in petri dishes and aged analogously to the thin

• /TiO2 film yielded statistically relevant data. The surface area and the pore diameter of the titania (cast TiO2 material, different batches) was determined by N2 sorption measurements (Autosorb MP1 and Quadrasorb, Quantachrome). The specific surface area was calculated using the Brunauer–Emmett–Teller

Enhanced visible light photocatalysis through fast crystallization of zinc oxide nanorods

• Sunandan Baruah,
• Mohammad Abbas Mahmood,
• Myo Tay Zar Myint,
• Tanujjal Bora and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2010, 1, 14–20, doi:10.3762/bjnano.1.3

• semiconductor undergo redox reactions with molecules adsorbed onto the surface, thereby breaking them into smaller fragments. Photocatalysis with metal-oxide-semiconductor nanostructures has been an area of intense research over the last couple of decades with titania (TiO2) receiving the most attention [1][2

• sites arising from oxygen nonstoichiometry, has emerged to be an efficient photocatalyst material compared to other metal oxides [8][9][10]. ZnO exhibits comparatively higher reaction and mineralization rates [11] and can generate hydroxyl ions more efficiently than titania (TiO2) [12]. Surface area and