Tubular glassy carbon microneedles with fullerene-like tips for biomedical applications

• Sharali Malik and
• George E. Kostakis

Beilstein J. Nanotechnol. 2022, 13, 455–461, doi:10.3762/bjnano.13.38

• . Figure 1b is a SEM detail image showing glassy carbon microneedles, nucleating microneedles, and “blisters”, which correspond to the early stages of the microneedle growth. Figure 1 shows that the microneedles grown under the given pyrolysis conditions are uniformly ca. 25 µm in diameter. The fullerene

• Figure 2b). Therefore, we consider the most likely growth mechanism to be that proposed by S. Amelinckx and co-workers [16]. Their model explains the formation of multishell closure domes in which nucleation is attributed to the initial formation of fullerene domes. These originate from the “blisters

• pyrolysis. These are transitory species and do not remain in the glassy carbon tubules. The early stages of this process can be seen, in Figure 1b, as the nucleation “blisters” on the surface of the glassy carbon formed on the alumina. These then develop into glassy carbon microneedles. Conclusion In this

A review of defect engineering, ion implantation, and nanofabrication using the helium ion microscope

• Frances I. Allen

Beilstein J. Nanotechnol. 2021, 12, 633–664, doi:10.3762/bjnano.12.52

• implantation phenomena (such as the formation of helium nanobubbles and blisters), as well as the opportunity to leverage these phenomena for practical applications. Using the HIM, individual grains/interfaces/regions of interest can be irradiated with a known dose of ions for systematic studies on the

• blisters At higher doses, the vacancies and interstitials that form in a crystalline material upon helium ion irradiation can diffuse and combine to form helium nanobubbles. And upon increasing the irradiation dose further, nanobubbles can coalesce to form larger cavities. Eventual rupture of cavities

Oxidation of Au/Ag films by oxygen plasma: phase separation and generation of nanoporosity

• Abdel-Aziz El Mel,
• Said A. Mansour,
• Mujaheed Pasha,
• Atef Zekri,
• Janarthanan Ponraj,
• Akshath Shetty and
• Yousef Haik

Beilstein J. Nanotechnol. 2020, 11, 1608–1614, doi:10.3762/bjnano.11.143

•  8b). In the second stage of the reaction, the highly stressed oxidized layer cracks and peels in some areas, allowing for fresh patches of metallic silver to be exposed to the plasma oxygen. Subsequently, cracks and blisters are generated again in the newly formed oxide layer due to the high internal

Disorder in H⁺-irradiated HOPG: effect of impinging energy and dose on Raman D-band splitting and surface topography

• Lisandro Venosta,
• Noelia Bajales,
• Sergio Suárez and
• Paula G. Bercoff

Beilstein J. Nanotechnol. 2018, 9, 2708–2717, doi:10.3762/bjnano.9.253

• characterization showed a distribution of surface defects, which were ascribed to the burst of hydrogen blisters formed as a consequence of the irradiation process. The results presented in this work contribute to the current trend in nanotechnology in areas devoted to the control of properties by defect

• matrix, in bubbles or blisters located amongst the graphene layers. The defective topography of the irradiated samples observed in Figure 5b,c is interpreted as a consequence of the bursting of H blisters. Taking into account the work of Waqar et al. [22], we have estimated the pressure inside one of

• such blisters considering half ellipsoids with a mean volume given by the mean size obtained from AFM data. For sample LD-LE, we obtain pLD-LE ≈ 2 × 106 Pa, and for sample HD-LE it is pHD-LE ≈ 4 × 107 Pa. Considering that typical values of tensile and compressive strengths of graphite are of the order

Optimization of Mo/Cr bilayer back contacts for thin-film solar cells

• Nima Khoshsirat,
• Fawad Ali,
• Vincent Tiing Tiong,
• Mojtaba Amjadipour,
• Hongxia Wang,
• Mahnaz Shafiei and
• Nunzio Motta

Beilstein J. Nanotechnol. 2018, 9, 2700–2707, doi:10.3762/bjnano.9.252

• with those films deposited at 5 mTorr. Blister-shaped features appeared on the samples deposited at 5 mTorr possibly due to micro-bubbles of Ar gas trapped in the Mo layer [34]. The appearance of blisters on the sample surface decreases when the sputtering power is increased. The differences in surface

Blister formation during graphite surface oxidation by Hummers’ method

• Olga V. Sinitsyna,
• Georgy B. Meshkov,
• Anastasija V. Grigorieva,
• Alexander A. Antonov,
• Inna G. Grigorieva and
• Igor V. Yaminsky

Beilstein J. Nanotechnol. 2018, 9, 407–414, doi:10.3762/bjnano.9.40

• (Figure S1, Supporting Information File 1). As mentioned above, we do not observe the deep-seated edge dislocation in AFM images. AFM examination of the HAPG surface after the treatment The AFM study after the treatment showed that the HAPG surface was covered with blisters (Figure 4). The blisters are

• unevenly arranged over the surface and have a wide size distribution. We found blisters with a diameter from 14 nm to 1430 nm and a height from 0.5 nm to 187 nm. The root mean square roughness measured in images with an area of 100 μm2 increased from 1–2 nm to ≈100 nm. The formation of blisters occurs if

• the HAPG interacts with the oxidation mixture just for a few minutes, which is confirmed by the results of an experiment in which the exposure time was reduced to 3 min. A typical image of the blisters is shown in Figure S2, Supporting Information File 1. Similar structures were previously observed on

Evolution of the graphite surface in phosphoric acid: an AFM and Raman study

• Rossella Yivlialin,
• Luigi Brambilla,
• Gianlorenzo Bussetti,
• Matteo Tommasini,
• Andrea Li Bassi,
• Carlo Spartaco Casari,
• Matteo Passoni,
• Franco Ciccacci,
• Lamberto Duò and
• Chiara Castiglioni

Beilstein J. Nanotechnol. 2016, 7, 1878–1884, doi:10.3762/bjnano.7.180

• sheets by delaminating graphite in (electro-)chemical baths. The observed phenomenology during the electrochemical treatment in phosphoric acid solution is partially different from other acidic solutions, such as sulfuric and perchloric acid solutions, where the graphite surface mainly forms blisters. In

• the main characteristics of the graphite crystals subjected to EC delamination [6][7] have been studied extensively. This allows one to shed light on the correlation between the modifications induced on the graphite crystal and the structure of the exfoliated graphene sheets. H2SO4 produces blisters

• by graphite oxidation [7][8]. HClO4 solutions show a similar phenomenology during intercalation of anions [7]. In particular, the evolution of blisters as a function of time has been analyzed in the past [9][10], supporting the theoretical model proposed by Murray [11]. H3PO4 is another solvent that

Direct formation of gold nanorods on surfaces using polymer-immobilised gold seeds

• Majid K. Abyaneh,
• Pietro Parisse and
• Loredana Casalis

Beilstein J. Nanotechnol. 2016, 7, 809–816, doi:10.3762/bjnano.7.72

• polymer matrix, and formed Au nanoparticles can be observed on top of them. This means that there are few blisters formed on the polymer surface during UV irradiation. Figure 3 shows AFM images for low- and high-Mw PMMA matrices with 60 wt % gold salt which are denominated as P1-60 and P2-60, respectively

Characterization of spherical domains at the polystyrene thin film–water interface

• Khurshid Ahmad,
• Xuezeng Zhao,
• Yunlu Pan and
• Danish Hussain

Beilstein J. Nanotechnol. 2016, 7, 581–590, doi:10.3762/bjnano.7.51

• , their insensitivity to lateral force, absence of long-range hydrophobic attraction, and the presence of possible contaminants and scratches on these domains suggested that these objects are most likely blisters formed by the stretched PS film. Furthermore, the analysis of the PS film before and after

• contact with water suggested that the film stretches and deforms after being exposed to water. The permeation of water at the PS–silicon interface, caused by osmosis or defects present on the film, can be a reasonable explanation for the nucleation of these spherical domains. Keywords: AFM; blisters

• reported different phenomena on the PS-coated surface such as dewetting from the silicon surface and formation of nanoindents and blisters [11][25][26][27][28]. It has been shown that the PS film can be dewetted from the silicon surface upon the contact with water [11]. Wang et al. [25] found that the

Digging gold: keV He⁺ ion interaction with Au

• Vasilisa Veligura,
• Gregor Hlawacek,
• Robin P. Berkelaar,
• Raoul van Gastel,
• Harold J. W. Zandvliet and
• Bene Poelsema

Beilstein J. Nanotechnol. 2013, 4, 453–460, doi:10.3762/bjnano.4.53

• dependence on the ion fluence. Simultaneously, helium implantation occurs. Depending on the fluence and primary energy, porous nanostructures or large blisters form on the sample surface. The growth of the helium bubbles responsible for this effect is discussed. Keywords: formation and healing of defects in

• formation (Figure 2h) and eventually the formation of a large subsurface helium blister at a fluence of 6 × 1017 cm−2 (Figure 2i). We also observe some pores on the surface of the blister. In Figure 3a two blisters on grains with different azimuthal orientation are shown. Although severe damage has been

• done to the surface and bulk of the gold grains, their crystalline nature is still evident. The blisters have equilateral triangles on top. The same triangles are also observed in the BSHe images, hinting at the channeling nature of the contrast. We attribute these dark triangles and rings to

Electronic and transport properties of kinked graphene

• Jesper Toft Rasmussen,
• Tue Gunst,
• Peter Bøggild,
• Antti-Pekka Jauho and
• Mads Brandbyge

Beilstein J. Nanotechnol. 2013, 4, 103–110, doi:10.3762/bjnano.4.12

• sheet while partly suspended across small holes, so that a pressure difference between the in- and outside leads to the formation of bubbles or “blisters” in the sheet [14]. Also, linear folds, where the graphene sheet is bulging up from the substrate, have been induced for graphene suspended over

• , decoration and pinning of the edges of other geometries such as “bubbles” or “blisters” is of interest, e.g., in order to produce GAL-like structures [7] without perforating the graphene sheet. Calculations have shown how the adsorption of hydrogen is correlated over a length scale involving several of the

Pure hydrogen low-temperature plasma exposure of HOPG and graphene: Graphane formation?

• Baran Eren,
• Dorothée Hug,
• Laurent Marot,
• Rémy Pawlak,
• Marcin Kisiel,
• Roland Steiner,
• Dominik M. Zumbühl and
• Ernst Meyer

Beilstein J. Nanotechnol. 2012, 3, 852–859, doi:10.3762/bjnano.3.96

• rougher, and (ii) blisters start to form, which are more pronounced for longer plasma exposures (Figure 2a and Figure 2b). Regarding these AFM measurements, it is clear that both surface roughening and blister formation contribute to D and D' peaks of the Raman spectrum. The surface roughening can neither

• , the graphite layers start to deform more rigorously and blisters start to appear on the surface. The different phase contrast of the blisters from the rest of the surface suggests that they have different local elastic properties than elsewhere on the HOPG (Figure 2c). It is, however, not clear

• whether these blisters still contain hydrogen gas underneath them during storage of HOPG under ambient conditions. Similar blister formation was observed after thermal sorption of hydrogen into graphite, and hydrogen gas storage was claimed by thermal desorption experiments [31]. AFM topography images of