Recent progress in magnetic applications for micro- and nanorobots

• Ke Xu,
• Shuang Xu and
• Fanan Wei

Beilstein J. Nanotechnol. 2021, 12, 744–755, doi:10.3762/bjnano.12.58

• sensor can approach F-sub, and then F-sub cutting and fluorescence signal amplification are carried out in the presence of analytes. Bakshi et al. proposed a cellular nanoreactor. It had two kinds of magnetic particles, each of which is functionalized by two components of the binary deoxyribozyme system

• , with which cancer cells and non-cancerous cells can be distinguished. Furthermore, a cell sensor that uses MaBiDz for rapid detection and imaging of target mRNA biomarkers of metastatic breast cancer has been realized. Its function shows that it is likely to be used as a biomimetic organelle MNR in the

Nanogenerator-based self-powered sensors for data collection

• Yicheng Shao,
• Maoliang Shen,
• Yuankai Zhou,
• Xin Cui,
• Lijie Li and
• Yan Zhang

Beilstein J. Nanotechnol. 2021, 12, 680–693, doi:10.3762/bjnano.12.54

• . Keywords: data collection; Internet of Things; nanogenerator; self-powered sensor; wearable device; Introduction Self-powered sensor systems can harvest and convert environmental energy to electricity, which enables sensor operation without external power source [1][2]. Nanogenerators (NGs) can

• approximately 100%) TENG (WP-TENG) based on a poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) electrode and installed the WP-TENG-based self-powered motion sensor at different positions of a human arm. The WP-TENG was placed on the skin above the muscles of the arm, as shown in Figure 2a

• . When the arm is bent, the muscles stretch the sensor to a larger contact area, and a voltage variation is generated by the sensor. An output voltage of about 23 V is generated. When the arm is released, the voltage returns to zero. The peak voltage varies with the bending angle of the elbow, as shown

Local stiffness and work function variations of hexagonal boron nitride on Cu(111)

• Abhishek Grewal,
• Yuqi Wang,
• Matthias Münks,
• Klaus Kern and
• Markus Ternes

Beilstein J. Nanotechnol. 2021, 12, 559–565, doi:10.3762/bjnano.12.46

• , CH-1015 Lausanne, Switzerland II. Institute of Physics, RWTH Aachen University, D-52074 Aachen, Germany 10.3762/bjnano.12.46 Abstract Combined scanning tunnelling and atomic force microscopy using a qPlus sensor enables the measurement of electronic and mechanic properties of two-dimensional

Influence of electrospray deposition on C₆₀ molecular assemblies

• Antoine Hinaut,
• Sebastian Scherb,
• Sara Freund,
• Zhao Liu,
• Thilo Glatzel and
• Ernst Meyer

Beilstein J. Nanotechnol. 2021, 12, 552–558, doi:10.3762/bjnano.12.45

• were obtained. Room-temperature AFM Room-temperature nc-AFM measurements were performed with a custom-built non-contact atomic force microscope with Nanonis electronics RC5. PPP-NCL cantilevers (Nanosensor) were used as sensor (typical resonance frequency of f1 = 170 kHz, oscillation amplitude A1 = 2–5

On the stability of microwave-fabricated SERS substrates – chemical and morphological considerations

• Limin Wang,
• Aisha Adebola Womiloju,
• Christiane Höppener,
• Ulrich S. Schubert and
• Stephanie Hoeppener

Beilstein J. Nanotechnol. 2021, 12, 541–551, doi:10.3762/bjnano.12.44

• processing time was completed in 4 min. During a typical reaction, the temperature rises up to 140–160 °C and the pressure is between 7 to 9 bars. It is important to note that these temperature measurements provide values that are measured by an external IR sensor placed close to the reaction vial and do not

Determining amplitude and tilt of a lateral force microscopy sensor

• Oliver Gretz,
• Alfred J. Weymouth,
• Thomas Holzmann,
• Korbinian Pürckhauer and
• Franz J. Giessibl

Beilstein J. Nanotechnol. 2021, 12, 517–524, doi:10.3762/bjnano.12.42

• ]. This has been used to achieve atomic resolution of a sample that is laterally stiff and vertically soft [5]. It has also been used under ultrahigh-vacuum conditions [6] as well as in liquid to yield atomic resolution [7]. Also in 2002, Giessibl and co-workers performed LFM using a qPlus sensor as shown

• molecular adsorbate [11][12]. Moreover, other methods, including the use of a long tip on a qPlus sensor that oscillates laterally at a higher flexural mode are also possible [13]. In LFM or normal AFM, the recorded frequency shift Δf is related to the force gradient kts in the direction of the tip

• oscillation. For a sensor oscillating in the x-direction, where F is the component of force in the x-direction and U is the potential energy. In general, the relevant force gradient at a spatial coordinate (x, z) for a tip oscillating at an angle θ with respect to the x-direction is: The frequency shift is

Simulation of gas sensing with a triboelectric nanogenerator

• Kaiqin Zhao,
• Hua Gan,
• Huan Li,
• Ziyu Liu and
• Zhiyuan Zhu

Beilstein J. Nanotechnol. 2021, 12, 507–516, doi:10.3762/bjnano.12.41

• gas and the different gas injection areas. This work contributes to the area of self-powered gas sensing. Keywords: gas; sensor; triboelectric nanogenerator (TENG); Introduction With economic development and social progress, there is an increasing demand for wearable [1][2][3][4], medical [5], and

• presence of a specific gas or the content of gas in ambient air. Therefore, gas sensors are usually indispensable in safety systems. Ordinary sensors need to be charged externally, and once the power is used up, the gas sensor loses its function. TENGs generate electricity that can be used for developing

• that of the right-angled side. It can be concluded that the rectangular TENG is economical and can achieve good electronic output. We considered designing a TENG-based gas sensor that could be used to detect different gases under real-life conditions. When, in contact separation mode, two triboelectric

A stretchable triboelectric nanogenerator made of silver-coated glass microspheres for human motion energy harvesting and self-powered sensing applications

• Hui Li,
• Yaju Zhang,
• Yonghui Wu,
• Hui Zhao,
• Weichao Wang,
• Xu He and
• Haiwu Zheng

Beilstein J. Nanotechnol. 2021, 12, 402–412, doi:10.3762/bjnano.12.32

• -coated glass microspheres (S-TENG). The S-TENG exhibits a remarkable performance in harvesting human motion energy and as flexible tactile sensor. By optimizing the device parameters and operating conditions, the maximum open-circuit voltage and short-circuit current of the S-TENG can reach up to 370 V

• source for electronic devices. Another potential application for the S-TENG is as flexible tactile sensor that can serve as electronic skin for a more comfortable interactive experience between humans and external objects by sensing all kinds of information, such as size, shape, and texture [26][27]. The

• flexible tactile sensor can generate electrical signals in response to different mechanical stimuli for the self-supply with energy. An S-TENG with an area of 20 × 20 mm2 was placed on each of five fingertips, as exhibited in Figure 6a. When the thumb touches index finger, middle finger, ring finger and

Structural and optical characteristics determined by the sputtering deposition conditions of oxide thin films

• Petronela Prepelita,
• Florin Garoi and
• Valentin Craciun

Beilstein J. Nanotechnol. 2021, 12, 354–365, doi:10.3762/bjnano.12.29

• others. Among the important applications of these oxides are materials with dielectric properties used in the fabrication of metasurface structures, transparent conductive oxides and buffer layers used in solar cells, and materials used in sensor technology [6][8][17][18][19][20][21]. Materials with

Nickel nanoparticle-decorated reduced graphene oxide/WO₃ nanocomposite – a promising candidate for gas sensing

• Ilka Simon,
• Alexandr Savitsky,
• Rolf Mülhaupt,
• Vladimir Pankov and
• Christoph Janiak

Beilstein J. Nanotechnol. 2021, 12, 343–353, doi:10.3762/bjnano.12.28

• pollutants and their emissions are harmful for humans and ecosystems [1]. Sensor materials that can detect the type and concentration of these gases are therefore needed in various kinds of environments and industries [2]. A gas sensor should be highly sensitive and highly selective with a fast response and

• in sensor resistance during exposure to the gas is measured directly [5]. Gases can either be oxidizing, such as NO, N2O, NO2, O3, and Cl2, reducing, such as H2S, NH3, CO, H2, SO2, and CH4, or rather inert, such as CO2 [6][7]. VOCs are organic molecules such as acetone, ethanol, and formaldehyde [8

• , and greater stability than pure WO3 [20]. WO3 decorated with palladium nanoparticles on the surface can be used as an improved and reusable gas sensor for NH3 [21]. Metal oxide semiconductor junctions can either be formed between two p-type MOS or two n-type MOS (p–p/n–n homojunctions) or between a p

Intracranial recording in patients with aphasia using nanomaterial-based flexible electronics: promises and challenges

• Qingchun Wang and
• Wai Ting Siok

Beilstein J. Nanotechnol. 2021, 12, 330–342, doi:10.3762/bjnano.12.27

• sensors could be implanted for iEEG recording. Sensor group cortical surface (CS) are strips and grids of electrodes, and sensor groups trans-occipital (TO) and orthogonal-to-mesial (OM) represent in-depth electrodes. Figure 2b was reprinted from [45], Physiological Measurement, vol. 39, by A. Sanz-Garcia

Scanning transmission helium ion microscopy on carbon nanomembranes

• Daniel Emmrich,
• Annalena Wolff,
• Nikolaus Meyerbröker,
• Jörg K. N. Lindner,
• André Beyer and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2021, 12, 222–231, doi:10.3762/bjnano.12.18

• detector in the dark field [20]. Kavanagh et al. used a silicon diode array as a pixelated sensor for transmission imaging to observe ion beam scattering with a static beam and as an end-point detection for pore milling into graphite sheets [21]. This work presents the design and capabilities of a dark

Paper-based triboelectric nanogenerators and their applications: a review

• Jing Han,
• Nuo Xu,
• Yuchen Liang,
• Mei Ding,
• Junyi Zhai,
• Qijun Sun and
• Zhong Lin Wang

Beilstein J. Nanotechnol. 2021, 12, 151–171, doi:10.3762/bjnano.12.12

• various types of human motions, such as stretching, lifting, and twisting [129]. The origami P-TENG could also serve as a self-powered pressure sensor to distinguish, for example, the weight difference between different coins. Miura-ori, a classic folding structure proposed by Miura, has been applied in

• , including acoustic [103], pressure/force/weight [129][145][146], velocity/acceleration [136][147], position [148], anti-theft [149], and temperature [145] sensors. Liu et al. [146] reported a self-powered active P-TENG force sensor with an ionogel-infiltrated paper (IIP) as the electrode, aiming for a

• flexible all paper-based sensor. The upper ionogel-infiltrated paper-based flexible electrode was adhered to the back side of the filter paper as the upper triboelectrification layer, while the counter friction layer corresponded to the bottom ionogel-infiltrated paper attached inside of the filter paper

Numerical analysis of vibration modes of a qPlus sensor with a long tip

• Kebei Chen,
• Zhenghui Liu,
• Yuchen Xie,
• Chunyu Zhang,
• Gengzhao Xu,
• Wentao Song and
• Ke Xu

Beilstein J. Nanotechnol. 2021, 12, 82–92, doi:10.3762/bjnano.12.7

• . The vibration modes of a qPlus sensor with a long tip are quite different from those of a cantilever with a short tip. Flexural vibration of the tungsten tip will occur. The tip can no longer be considered as a rigid body that moves with the prong of the tuning fork. Instead, it oscillates both

• the optimal diameter was found to be 0.1 mm. Keywords: finite element method; long tilted tip; noncontact atomic force microscopy; qPlus sensor; quartz tuning fork; simulations; Introduction Quartz tuning forks are widely used in the watch industry because of their low frequency offset over a wide

• temperature range [1]. In addition, quartz tuning forks have a high elastic constant, a high quality factor (Q factor), and are self-sensing due to the piezoelectric effect [1]. Therefore, a quartz tuning fork can be used as a force sensor. The central part of the “qPlus sensor” is a quartz tuning fork of

Piezotronic effect in AlGaN/AlN/GaN heterojunction nanowires used as a flexible strain sensor

• Jianqi Dong,
• Liang Chen,
• Yuqing Yang and
• Xingfu Wang

Beilstein J. Nanotechnol. 2020, 11, 1847–1853, doi:10.3762/bjnano.11.166

• synthesize AlGaN/AlN/GaN heterojunction NWs with controllable size. A single NW is transferred to a flexible poly(ethylene terephthalate) substrate and fixed by indium tin oxide electrodes to form an ohmic contact for the strain sensor. An external mechanical stress is introduced to study the performance of

• the fabricated piezotronic strain sensor. The gauge factor is as high as 30 under compressive or tensile stress, which indicates a high sensitivity of the strain sensor. Periodic strain tests show the high stability and repeatability of the sensor. The working mechanism of the strain sensor is

• investigated and systematically analyzed under compressive and tensile strain. Here, we describe a strain sensor that shows a great application potential in wearable integrated circuits, in health-monitoring devices, and in artificial intelligence. Keywords: AlGaN/AlN/GaN nanowires; flexible; piezotronic

Mapping of integrated PIN diodes with a 3D architecture by scanning microwave impedance microscopy and dynamic spectroscopy

• Rosine Coq Germanicus,
• Peter De Wolf,
• Florent Lallemand,
• Catherine Bunel,
• Serge Bardy,
• Hugues Murray and
• Ulrike Lüders

Beilstein J. Nanotechnol. 2020, 11, 1764–1775, doi:10.3762/bjnano.11.159

• -frequency (approx. 100 kHz) AC voltage (VAC) is applied to the tip–sample system in order to generate the movement of free carriers [18]. At a fixed DC bias, the capacitance variation is measured with a highly sensitive capacitance sensor with a sensitivity of approx. 10−19 F·Hz−1/2. In addition, the

• BEOL steps were accomplished. The SPM electrical measurements were performed in the cross section of the chip at the wafer level. In order to enable a stable and constant nanoscale contact between the sensor tip and the sample, a surface with a low roughness is required. For this purpose, the sample

Piezoelectric sensor based on graphene-doped PVDF nanofibers for sign language translation

• Shuai Yang,
• Xiaojing Cui,
• Rui Guo,
• Zhiyi Zhang,
• Shengbo Sang and
• Hulin Zhang

Beilstein J. Nanotechnol. 2020, 11, 1655–1662, doi:10.3762/bjnano.11.148

• /bjnano.11.148 Abstract The tracking of body motion, such as bending or twisting, plays an important role in modern sign language translation. Here, a subtle flexible self-powered piezoelectric sensor (PES) made of graphene (GR)-doped polyvinylidene fluoride (PVDF) nanofibers is reported. The PES exhibits

• effectively used, especially in human–computer interaction, such as gesture control, rehabilitation training, and auxiliary communication. Keywords: motion sensor; piezoelectric; polyvinylidene fluoride (PVDF); self-powered; sign language translation; Introduction Sign language, as a communication method

• are gradually showing rich application prospects in sign language learning and daily communication. A recently reported yarn-based stretchable sensor can already translate a large number of gestures into speech signals [1][2][3][4][5][6]. However, traditional real-time sign language translation

Selective detection of complex gas mixtures using point contacts: concept, method and tools

• Alexander P. Pospelov,
• Victor I. Belan,
• Dmytro O. Harbuz,
• Volodymyr L. Vakula,
• Lyudmila V. Kamarchuk,
• Yuliya V. Volkova and
• Gennadii V. Kamarchuk

Beilstein J. Nanotechnol. 2020, 11, 1631–1643, doi:10.3762/bjnano.11.146

• 10.3762/bjnano.11.146 Abstract Of all modern nanosensors using the principle of measuring variations in electric conductance, point-contact sensors stand out in having a number of original sensor properties not manifested by their analogues. The nontrivial nature of point-contact sensors is based on the

• mixture it is possible to get a functional dependence of the concentration of particular breath components on the amplitude of the sensor output signal. To demonstrate the feasibility of the proposed approach, we analyze the point-contact profiles from the breath of several patients and compare them with

• breath test. The present study indicates some necessary prerequisites for the design of fast detection methods using differential sensor analysis in real time, which can be implemented in various areas of science and technology, among which medicine is one of the most important. Keywords: breath profile

A self-powered, flexible ultra-thin Si/ZnO nanowire photodetector as full-spectrum optical sensor and pyroelectric nanogenerator

• Liang Chen,
• Jianqi Dong,
• Miao He and
• Xingfu Wang

Beilstein J. Nanotechnol. 2020, 11, 1623–1630, doi:10.3762/bjnano.11.145

• work, a new type of self-powered, high-performance ultra-thin p-Si/n-ZnO nanowire (NW) flexible photodetector (PD) and its application as full-spectrum optical sensor and pyroelectric nanogenerator (PENG) are demonstrated. The working mechanism of PDs for PENGs is carefully investigated and

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

• oxide [1][2]. With the recent advancements in nanotechnology, this unique phenomenon received more attention since it can be used to generate nanoporous materials which are applicable in many areas, including drug delivery, biotechnology and sensor development. The interest in nanoporous materials

Walking energy harvesting and self-powered tracking system based on triboelectric nanogenerators

• Mingliang Yao,
• Guangzhong Xie,
• Qichen Gong and
• Yuanjie Su

Beilstein J. Nanotechnol. 2020, 11, 1590–1595, doi:10.3762/bjnano.11.141

• electronics [1][2][3][4][5] and wireless sensor networks is in high demand. Mechanical energy, which is widely distributed in the environment, is one of the most general power sources. The human body is a rich source of mechanical energy [6]. Muscle stretching, for example, converts biochemical energy into

Wafer-level integration of self-aligned high aspect ratio silicon 3D structures using the MACE method with Au, Pd, Pt, Cu, and Ir

• Mathias Franz,
• Romy Junghans,
• Paul Schmitt,
• Adriana Szeghalmi and
• Stefan E. Schulz

Beilstein J. Nanotechnol. 2020, 11, 1439–1449, doi:10.3762/bjnano.11.128

• by an in situ micro quartz crystal sensor. The particle formation has been done by thermal annealing under vacuum conditions. The wafers with Cu and Pt have been annealed in vacuo, while the wafers with Au and Pd were annealed ex situ. Each annealing consists of a heating phase, 30 min of annealing

Triboelectric nanogenerator based on Teflon/vitamin B1 powder for self-powered humidity sensing

• Liangyi Zhang,
• Huan Li,
• Yiyuan Xie,
• Jing Guo and
• Zhiyuan Zhu

Beilstein J. Nanotechnol. 2020, 11, 1394–1401, doi:10.3762/bjnano.11.123

• measured open-circuit voltage was approximately 340 V. The TVB-TENG can be applied as a humidity sensor and exhibits a linear and reversible response to the relative humidity of the environment. Moreover, the change in relative humidity is also indicated by the change in luminosity of a set of light

• -emitting diodes (LEDs) integrated in the TVB-TENG system. The TVB-TENG proposed in this study illustrates a cost-effective method for portable power supply and sensing devices. Keywords: humidity sensor; self-powered system; triboelectric nanogenerators (TENGs); triboelectrification; vitamin B1

• , food safety, wearable electronics, and wireless sensor networks [1][2][3][4]. However, conventional power generation is needed to supply energy to these sensor networks, which leads to increased energy usage and adverse impacts on the environment. More specifically, the degradation of the urban

An atomic force microscope integrated with a helium ion microscope for correlative nanoscale characterization

• Santiago H. Andany,
• Gregor Hlawacek,
• Stefan Hummel,
• Charlène Brillard,
• Mustafa Kangül and
• Georg E. Fantner

Beilstein J. Nanotechnol. 2020, 11, 1272–1279, doi:10.3762/bjnano.11.111

• closed-loop sensor data obtained prior to imaging on the AFM scan head. For Figure 2, the AFM image shown was recorded at 300 mHz line rate at a resolution of 1024 pixels and 512 lines and over a scan range of 30 × 30 µm. The imaging mode used was off-resonance tapping (ORT) at a tapping rate of 2 kHz

Ultrasensitive detection of cadmium ions using a microcantilever-based piezoresistive sensor for groundwater

• Dinesh Rotake,
• Anand Darji and
• Nitin Kale

Beilstein J. Nanotechnol. 2020, 11, 1242–1253, doi:10.3762/bjnano.11.108

• – 76, India. 10.3762/bjnano.11.108 Abstract This paper proposes the selective and ultrasensitive detection of Cd(II) ions using a cysteamine-functionalized microcantilever-based sensor with cross-linked ᴅʟ-glyceraldehyde (DL-GC). The detection time for various laboratory-based techniques is generally

• only on absorption and fluorescence change and need dynamic acquisition [23]. A magnetic field powered pressure sensor proposed by Khan et al. [24] is capable of measuring pressure in the range of kilopascals but the suitability for the very low pressure caused by HMIs needs to be examined. A reduced

• graphene oxide (RGO)-based sensor and a microfluidic platform fabricated by [25][26][27] can be used with some surface modification for HMIs, but it is mostly capable of detecting in the micromolar range. A polymer-based microcantilever using an encapsulated piezoresistor has been proposed by Kale et al