Bolometric IR photoresponse based on a 3D micro-nano integrated CNT architecture

• Yasameen Al-Mafrachi,
• Sandeep Yadav,
• Sascha Preu,
• Jörg J. Schneider and
• Oktay Yilmazoglu

Beilstein J. Nanotechnol. 2024, 15, 1030–1040, doi:10.3762/bjnano.15.84

• 600 nm thick thermally oxidized SiO2 layer. The wafer was p-type and lightly boron-doped (Si-Mat, Silicon Materials). The substrate was thoroughly cleaned to remove impurities and contaminants to provide an ideal condition for CNT growth. Subsequently, an essential 30 nm aluminum oxide (AlOx) layer

• was deposited by atomic layer deposition to support the elongated growth of CNTs (Figure 1a). The contact pad regions were opened by an optical lithography process prior to the evaporation of Cr/Au (20 nm, e-beam/100 nm, thermal) (Figure 1b). The overall M-shape for the CNT growth as shown in Figure

•  1c was defined by overlapping two tantalum-based growth stop strips (150 nm, sputtering) with a rectangular Fe layer (2 nm, e-beam) on the Si wafer. Only regions with direct Fe/AlOx contact were active for CNT growth. This combination allows for the definition of any shape, offering versatility for

Control of morphology and crystallinity of CNTs in flame synthesis with one-dimensional reaction zone

• Muhammad Hilmi Ibrahim,
• Norikhwan Hamzah,
• Mohd Zamri Mohd Yusop,
• Ni Luh Wulan Septiani and
• Mohd Fairus Mohd Yasin

Beilstein J. Nanotechnol. 2023, 14, 741–750, doi:10.3762/bjnano.14.61

• on the growth control in CVD conclude that independent parameters, such as fuel selection, synthesis temperature, vapor pressure, and catalyst, govern CNT growth [6]; all can be manipulated for synthesis control. CVD is preferred because of the high degree of control and the possibility to synthesize

• at relatively low temperatures. However, CVD consumes a lot of energy for CNT growth, leading to increased production cost and, thus, making high-quality CNTs too expensive for practical applications. Alternatively, similar growth mechanisms of CNTs using the less common flame synthesis method are

• control to achieve stable growth conditions. Yet, achieving independent parametric control in flame synthesis is a challenging task. In a diffusion flame, specific locations within the flame are imperative and conducive for CNT growth, depending on height above burner (HAB), local distance from the flame

Studies of probe tip materials by atomic force microscopy: a review

• Ke Xu and
• Yuzhe Liu

Beilstein J. Nanotechnol. 2022, 13, 1256–1267, doi:10.3762/bjnano.13.104

• prominent carbon nanotube tips. This type of process strategy is used to produce CNT tips in wafer-scale AFM. By identifying and manipulating the key growth conditions that control the density and length of carbon nanotube growth; i.e., the amount of Co catalyst and CNT growth time, it is possible to switch

Electrostatic pull-in application in flexible devices: A review

• Teng Cai,
• Yuming Fang,
• Yingli Fang,
• Ruozhou Li,
• Ying Yu and
• Mingyang Huang

Beilstein J. Nanotechnol. 2022, 13, 390–403, doi:10.3762/bjnano.13.32

• vertically on the substrate. The vertically aligned MWCNTs were prepared by various methods, such as the constriction of CNT growth by nanoscale pockets and DC plasma-enhanced chemical vapor deposition (PECVD), as shown in Figure 2c. Using the vertically aligned CNT switches provides a high density for

Facile synthesis of carbon nanotube-supported NiO//Fe₂O₃ for all-solid-state supercapacitors

• Shengming Zhang,
• Xuhui Wang,
• Yan Li,
• Xuemei Mu,
• Yaxiong Zhang,
• Jingwei Du,
• Guo Liu,
• Xiaohui Hua,
• Yingzhuo Sheng,
• Erqing Xie and
• Zhenxing Zhang

Beilstein J. Nanotechnol. 2019, 10, 1923–1932, doi:10.3762/bjnano.10.188

• a diameter of about 20 nm (Supporting Information File 1, Figure S1). The high conductivity of the CNTs will help charge transfer during the electrochemical process. As shown in Supporting Information File 1, Figure S2, the pure CC with a size of 1 × 1 cm2 is grey, it becomes black after CNT growth

Hierarchically structured 3D carbon nanotube electrodes for electrocatalytic applications

• Pei Wang,
• Katarzyna Kulp and
• Michael Bron

Beilstein J. Nanotechnol. 2019, 10, 1475–1487, doi:10.3762/bjnano.10.146

• the preparation of hierarchically structured CNTs on glassy carbon (GC) based on a sequential CNT growth over electrodeposited Fe nanoparticles via chemical vapor deposition (CVD) with cyclohexane as the carbon precursor. Pt electrodeposition onto these hierarchical structures leads to active

• nearly uniformly grown on the surface of GC with a diameter of approximately 40–80 nm. Accordingly, the optical image (Supporting Information File 1, Figure S2g) displays a matt black thin layer at those areas of the GC chips that were covered with Fe particles. However, no CNT growth was observed with a

• decreasing ratio of H2/Ar [63]. This demonstrates that the CNT growth strongly depends on the growth conditions. Accordingly, the above-described results reveal the sensitivity of the CNT growth on the H2/cyclohexane ratio under the chosen conditions. During CVD growth, hydrogen molecules or atoms keep the

SO₂ gas adsorption on carbon nanomaterials: a comparative study

• Deepu J. Babu,
• Divya Puthusseri,
• Frank G. Kühl,
• Sherif Okeil,
• Michael Bruns,
• Manfred Hampe and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2018, 9, 1782–1792, doi:10.3762/bjnano.9.169

• CNTs can be either randomly oriented or arranged parallel to each other resulting in a preferential alignment (Figure 1d). By the proper choice of synthesis parameters, the CNT growth orientation perpendicular to the substrate can be realized and such 3D CNT structures are referred to as vertically

Engineering of oriented carbon nanotubes in composite materials

• Razieh Beigmoradi,
• Abdolreza Samimi and
• Davod Mohebbi-Kalhori

Beilstein J. Nanotechnol. 2018, 9, 415–435, doi:10.3762/bjnano.9.41

• CNT growth, while in the latter, the CNTs are initially grown in random orientation and the arrangement is then achieved during the device integration process. As the ex situ techniques are free from growth restrictions and more flexible in terms of controlling the alignment and sorting of the CNTs

Dry adhesives from carbon nanofibers grown in an open ethanol flame

• Christian Lutz,
• Julia Syurik,
• C. N. Shyam Kumar,
• Christian Kübel,
• Michael Bruns and
• Hendrik Hölscher

Beilstein J. Nanotechnol. 2017, 8, 2719–2728, doi:10.3762/bjnano.8.271

• measurements and many helpful discussions related to CNT growth, Marco Heiler and Harald Leiste for the preparation of the thin films and Richard Thelen for support with the AFM based adhesion measurements. J.S. gratefully acknowledges funding from the Helmholtz Postdoc Programme (PD-157). The K-Alpha

One-step chemical vapor deposition synthesis and supercapacitor performance of nitrogen-doped porous carbon–carbon nanotube hybrids

• Egor V. Lobiak,
• Lyubov G. Bulusheva,
• Ekaterina O. Fedorovskaya,
• Yury V. Shubin,
• Pavel E. Plyusnin,
• Pierre Lonchambon,
• Boris V. Senkovskiy,
• Zinfer R. Ismagilov,
• Emmanuel Flahaut and
• Alexander V. Okotrub

Beilstein J. Nanotechnol. 2017, 8, 2669–2679, doi:10.3762/bjnano.8.267

• prepared hybrid materials [6][7][8][9]. Another less common strategy consists of CNT growth by catalytic chemical vapor deposition (CCVD) over catalyst nanoparticles predeposited on the graphitic surfaces [10][11][12][13]. The obtained hybrids are characterized by tight bonding between the components

• particles. The nucleation and growth of CNTs typically require stabilization of the catalytic nanoparticles at elevated temperatures, and MgO is often used for this purpose [18]. Rümmeli et al. have shown that under typical CCVD conditions for CNT growth and in the absence of a deposited catalyst, the MgO

Localized growth of carbon nanotubes via lithographic fabrication of metallic deposits

• Fan Tu,
• Martin Drost,
• Imre Szenti,
• Janos Kiss,
• Zoltan Kónya and
• Hubertus Marbach

Beilstein J. Nanotechnol. 2017, 8, 2592–2605, doi:10.3762/bjnano.8.260

• an Al2O3 layer on a silicon sample. A peculiar lift-up of the Fe seed structures as “flakes” was observed and the mechanism was discussed. Finally, a proof-of-principle was presented showing that EBID deposits from the precursor Co(CO)3NO are also very effective catalysts for the CNT growth. Even

• though the metal content (Co) of the latter is reduced in comparison to the Fe deposits, effective CNT growth was observed for the Co-containing deposits at lower CVD temperatures than for the corresponding Fe deposits. Keywords: autocatalytic growth; carbon nanotubes; cobalt tricarbonyl nitrosyl

• storage [1][2][3][4]. The most common synthesis method for CNTs is chemical vapor deposition (CVD) [5][6][7][8], in which statistically distributed, metal-containing particles act as catalysts for CNT growth. Thereby, not only does the random position of the catalyst particles determine the position of

A systematic study of the controlled generation of crystalline iron oxide nanoparticles on graphene using a chemical etching process

• Peter Krauß,
• Jörg Engstler and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2017, 8, 2017–2025, doi:10.3762/bjnano.8.202

• ) chloride in 10% hydrochloric acid. The ratio of copper to etchant was increased as described previously in order to obtain a higher number of iron oxide nanoparticles which serve as a catalyst for CNT growth. The water-assisted CVD growth of CNTs was then performed at 875 °C in an argon/hydrogen atmosphere

• of CNTs on iron oxide nanoparticles/graphene without introducing a carbon precursor during water-assisted CVD in order to see whether CNT growth is due to the carbon precursor employed. Therefore, apart from ethene gas flow, which was substituted by argon, all parameters for CNT synthesis were

• of iron oxide nanoparticles on graphene; a,b) before and c,d) after thermal annealing at 450 °C for 24 h in a hydrogen atmosphere. The nanoparticles are highly mobile and tend to agglomerate during the heat treatment procedure. Iron oxide decorated graphene layer on a SiO2/Si wafer for CNT growth

Reasons and remedies for the agglomeration of multilayered graphene and carbon nanotubes in polymers

• Rasheed Atif and
• Fawad Inam

Beilstein J. Nanotechnol. 2016, 7, 1174–1196, doi:10.3762/bjnano.7.109

• HiPco (high pressure CO) process. It is a CVD technique that does not use catalyst particles for CNT growth. It is a relatively economical and easily scalable process [2][36]. Most of the aforementioned methods yield CNTs of shorter lengths ranging between 0.05 and 3 μm [36]. CNTs can be prepared by

Possibilities and limitations of advanced transmission electron microscopy for carbon-based nanomaterials

• Xiaoxing Ke,
• Carla Bittencourt and
• Gustaaf Van Tendeloo

Beilstein J. Nanotechnol. 2015, 6, 1541–1557, doi:10.3762/bjnano.6.158

• between energetic electrons and matter plays a unique role in triggering the reaction. Taking CNT growth as an example, the formation mechanism of CNTs was under debate for years until 2007, when Rodriguez-Manzo et al. monitored the nucleation and growth of a SWCNT through an in situ heating experiment

Interaction of electromagnetic radiation in the 20–200 GHz frequency range with arrays of carbon nanotubes with ferromagnetic nanoparticles

• Agylych Atdayev,
• Alexander L. Danilyuk and
• Serghej L. Prischepa

Beilstein J. Nanotechnol. 2015, 6, 1056–1064, doi:10.3762/bjnano.6.106

• resistive–inductive–capacitive (RiLiCi) circuits, which leads to a deeper understanding of the problem. Such nanocomposites can be easily synthesized in situ during the CNT growth by chemical vapor deposition, which involves carbon decomposition of an organic precursor with 3d catalytic metals such as Fe

Growth and structural discrimination of cortical neurons on randomly oriented and vertically aligned dense carbon nanotube networks

• Christoph Nick,
• Sandeep Yadav,
• Ravi Joshi,
• Christiane Thielemann and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2014, 5, 1575–1579, doi:10.3762/bjnano.5.169

• gold. This assures a random CNT growth. In contrast, for the growth of the aligned CNT arrays, the growth substrate was silicon and the growth temperature was set to 800 °C with an ethylene flow of 100 sccm (all other conditions being the same as above). The CNTs obtained in this process are mainly

Gas sensing with gold-decorated vertically aligned carbon nanotubes

• Prasantha R. Mudimela,
• Mattia Scardamaglia,
• Oriol González-León,
• Nicolas Reckinger,
• Rony Snyders,
• Eduard Llobet,
• Carla Bittencourt and
• Jean-François Colomer

Beilstein J. Nanotechnol. 2014, 5, 910–918, doi:10.3762/bjnano.5.104

• layers were deposited under 2 mTorr and 20 mTorr pressures using radio frequency (RF) and direct current (DC) magnetron sputtering, respectively. For the CNT growth, the reactor was heated to 750 °C at atmospheric pressure under Ar flow (120 sccm). The catalyst was placed inside the reactor and the H2

Functionalization of vertically aligned carbon nanotubes

• Eloise Van Hooijdonk,
• Carla Bittencourt,
• Rony Snyders and
• Jean-François Colomer

Beilstein J. Nanotechnol. 2013, 4, 129–152, doi:10.3762/bjnano.4.14

• . Floating catalyst CVD involves vaporization and sublimation of a catalyst precursor on a substrate that is then introduced in a high-temperature zone where the growth of the CNTs takes place. Whether the CNT growth starts during the floating stage [31], or from metal particles deposited on substrates or on

• for the catalysts, which are then deposited by dip or spin coating or, alternatively, are filled into nanoporous architectures serving as templates for the CNT growth. Plasma vapor deposition is an efficient method for the preparation of thin films of metal catalysts with well-defined thicknesses. The

• /catalyst layer/alumina layer is used. During the CNT growth, the catalyst and alumina layers are lifted up and the CNTs grow vertically aligned, directly on the graphene layer. As a result of this strategy, no seam exists between the graphene and the nanotubes carpet. The introduction of the top alumina

Low-temperature synthesis of carbon nanotubes on indium tin oxide electrodes for organic solar cells

• Andrea Capasso,
• Luigi Salamandra,
• Aldo Di Carlo,
• John M. Bell and
• Nunzio Motta

Beilstein J. Nanotechnol. 2012, 3, 524–532, doi:10.3762/bjnano.3.60

• different behavior for two electrodes prepared with the same procedure must be explained in terms of the only parameter varied, i.e., the CVD time. Consistently with the widely known CNT growth mechanism, the shorter CVD time used for sample C1 (15 min) leads to a shorter length of the grown CNTs: as a

Structural, electronic and photovoltaic characterization of multiwalled carbon nanotubes grown directly on stainless steel

• Luca Camilli,
• Manuela Scarselli,
• Silvano Del Gobbo,
• Paola Castrucci,
• Eric Gautron and
• Maurizio De Crescenzi

Beilstein J. Nanotechnol. 2012, 3, 360–367, doi:10.3762/bjnano.3.42

• was introduced (200 sccm) into the chamber to start the CNT growth. After 10 min, the acetylene flow was stopped and argon (500 sccm) was inserted again for 5 min to stop the reaction, while the chamber was pumped off. More details are reported elsewhere [7]. AFM (VEECO multiprobe) characterization

Generation and agglomeration behaviour of size-selected sub-nm iron clusters as catalysts for the growth of carbon nanotubes

• Ravi Joshi,
• Benjamin Waldschmidt,
• Jörg Engstler,
• Rolf Schäfer and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2011, 2, 734–739, doi:10.3762/bjnano.2.80

• into [Al@SiOx] surfaces at a low surface coverage corresponding to a few thousandths up to a few hundredths of a monolayer in order to avoid initial cluster agglomeration. These studies are aimed towards gaining an insight into the lower limit of the size regime of carbon nanotube (CNT) growth by

• employing size-selected sub-nm iron clusters as catalyst or precatalyst precursors for CNT growth. Agglomeration of sub-nm iron clusters to iron nanoparticles with a median size range between three and six nanometres and the CNT formation hence can be observed at CVD growth temperatures of 750 °C. Below 600

• °C, no CNT growth is observed. Keywords: carbon nanotubes; CNT growth; metal clusters; size selected clusters; Introduction Controlling the individual diameters of carbon nanotubes (CNTs) is still one of the major challenges in current CNT research, and it is particularly important as it determines

Studies towards synthesis, evolution and alignment characteristics of dense, millimeter long multiwalled carbon nanotube arrays

• Pitamber Mahanandia,
• Jörg J. Schneider,
• Martin Engel,
• Bernd Stühn,
• Somanahalli V. Subramanyam and
• Karuna Kar Nanda

Beilstein J. Nanotechnol. 2011, 2, 293–301, doi:10.3762/bjnano.2.34

• early stages of the CNT growth. Nevertheless, there are reports on the vertical growth of up to mm long CNTs, even without the additional supply of such oxidizing agents [13][26][27][28]. Thus, the exact role of such promoters and oxidizers is still unclear. Despite the intensive studies towards this

• of CNTs. Once the initial CNT formation is established, CNT growth continues in the vertical direction and is further reinforced by the presence of nearby surrounding CNTs, which display multiple van der Waals force interactions and mechanically stabilize the large area growth in the vertical