Ordered arrays of nanoporous gold nanoparticles

• Dong Wang,
• Ran Ji,
• Arne Albrecht and
• Peter Schaaf

Beilstein J. Nanotechnol. 2012, 3, 651–657, doi:10.3762/bjnano.3.74

• schematically presented in Figure 1. The surface of a Si(100) wafer was patterned into a periodic array of pyramidal pits (Figure S1, Supporting Information File 1) by using SCIL, reactive ion etching (RIE), and KOH etching. The spatial period of these pits is 520 nm. A 200 nm layer of SiO2 was thermally grown

• acted as a mask during the anisotropic etching of Si in a KOH solution, and the Si surface was patterned into a periodic array of pyramidal pits. After removal of the SiO2 mask, about 20 nm of SiO2 was then again thermally grown on the structured Si surface to avoid a reaction between the subsequently

• spatial period. However, the pits were fabricated by KOH etching in this study and have a depth of about 360 nm, whereas the pits in the previous work were fabricated by reactive ion etching and have a depth of 150 nm. This means that a larger optimized thickness is required for the formation of an

Reduced electron recombination of dye-sensitized solar cells based on TiO₂ spheres consisting of ultrathin nanosheets with [001] facet exposed

• Hongxia Wang,
• Meinan Liu,
• Cheng Yan and
• John Bell

Beilstein J. Nanotechnol. 2012, 3, 378–387, doi:10.3762/bjnano.3.44

• nanosheets to realize a minimum surface energy. Some spheres have pits on the surface, which may be due to the insufficient reaction duration. The measurement of the N2 adsorption/desorption isotherms of the TiO2 powder shows that the specific surface area of the TiO2 spheres is 82 m2/g, which is slightly

Noncontact atomic force microscopy study of the spinel MgAl₂O₄(111) surface

• Morten K. Rasmussen,
• Kristoffer Meinander,
• Flemming Besenbacher and
• Jeppe V. Lauritsen

Beilstein J. Nanotechnol. 2012, 3, 192–197, doi:10.3762/bjnano.3.21

• of step edges. In the case of Zn-terminated ZnO(0001), a stabilization mechanism was proposed involving the formation of preferentially O-terminated edges and pits, which effectively lowers the excess amount of Zn on this polar surface and reduces the surface dipole [21][22]. To evaluate the effect

Quantitative multichannel NC-AFM data analysis of graphene growth on SiC(0001)

• Christian Held,
• Thomas Seyller and
• Roland Bennewitz

Beilstein J. Nanotechnol. 2012, 3, 179–185, doi:10.3762/bjnano.3.19

• , the surface structure remains the same upon oxide removal (Figure 2b). The width of the large terraces is slightly reduced and a number of smaller and larger pits and islands with lateral extensions of only a few nanometers up to hundreds of nanometers are found. Except for a few remaining rough spots

• significantly (Figure 1c). The largest atomically flat areas now have a lateral extension of only 100 nm. The sample is covered with small pits of hexagonal shape. A large variety of step heights is found (Table 1). Graphene grown in an argon atmosphere The same starting material and sample preparation, i.e

Formation of precise 2D Au particle arrays via thermally induced dewetting on pre-patterned substrates

• Dong Wang,
• Ran Ji and
• Peter Schaaf

Beilstein J. Nanotechnol. 2011, 2, 318–326, doi:10.3762/bjnano.2.37

• induced by annealing. Two types of pre-patterned substrates were used: The first comprised an array of pyramidal pits and the second an array of circular holes. For the dewetting of Au films on the pyramidal pit substrate, the structural curvature-driven diffusion cooperates with capillarity-driven

• crystallographic orientation, on a substrate with an array of periodic pits, via solid-state dewetting induced by annealing at 850 °C [9]. Our previous work showed that a pre-patterned substrate with deep grid grooves can also lead to the formation of a 2D ordered Au nanoparticle array via dewetting induced by

• . induced by annealing, has been studied, on both the flat substrate and two types of pre-patterned substrates (one with an array of pyramidal pits and one with an array of circular holes, made using nanoimprint lithography), and large areas of 2D ordered nanoparticle arrays were fabricated. Instead of the

Manipulation of gold colloidal nanoparticles with atomic force microscopy in dynamic mode: influence of particle–substrate chemistry and morphology, and of operating conditions

• Samer Darwich,
• Karine Mougin,
• Akshata Rao,
• Enrico Gnecco,
• Shrisudersan Jayaraman and
• Hamidou Haidara

Beilstein J. Nanotechnol. 2011, 2, 85–98, doi:10.3762/bjnano.2.10

• (FIB) milling technique. The width and depth of the pits are 650 nm and 5 nm, respectively, and the spacing between two adjacent pits is 125 nm. On the patterned surface, the mean direction of motion remains identical (on average), even after a long acquisition time. This stability of the direction of

• the particle movement observed here on the nanopatterned substrates can be attributed to "self-cleaning" of the tip when it crosses the shallow pits. Considering that the pits have only a small influence on the particle direction (Figure 9), which means that all the particles follow the same direction

• deposited onto a silicon wafer. (a) Ordered organization as described in the Experimental section, (b) random distribution. Frame sizes: 3 µm and 1 µm, respectively. As-synthesized Au particles on silicon in ultra-high vacuum. Frame size: 3 µm. AFM image of nanopatterned surface exhibiting Si pits: Frame

The description of friction of silicon MEMS with surface roughness: virtues and limitations of a stochastic Prandtl–Tomlinson model and the simulation of vibration-induced friction reduction

• W. Merlijn van Spengen,
• Viviane Turq and
• Joost W. M. Frenken

Beilstein J. Nanotechnol. 2010, 1, 163–171, doi:10.3762/bjnano.1.20

• simulation replicates even the fact that a vibrational amplitude with the frequency of the modulation is visible in the lateral force at high modulation amplitudes (‘wobbling in the pits’), and that its envelope has a correlation with the surface roughness. Only in the simulation these effects are smaller