Optimizing PMMA solutions to suppress contamination in the transfer of CVD graphene for batch production

• Chun-Da Liao,
• Andrea Capasso,
• Tiago Queirós,
• Telma Domingues,
• Fatima Cerqueira,
• Nicoleta Nicoara,
• Jérôme Borme,
• Paulo Freitas and
• Pedro Alpuim

Beilstein J. Nanotechnol. 2022, 13, 796–806, doi:10.3762/bjnano.13.70

• B2 mixture yields more consistent electric properties of the graphene channel, thanks to a homogenous and reproducible process. Such characteristics ultimately translate into a consistent sensor performance, which is pivotal for industrial fabrication. Conclusion Monolayer graphene films and single

A nonenzymatic reduced graphene oxide-based nanosensor for parathion

• Sarani Sen,
• Anurag Roy,
• Ambarish Sanyal and
• Parukuttyamma Sujatha Devi

Beilstein J. Nanotechnol. 2022, 13, 730–744, doi:10.3762/bjnano.13.65

• the fabrication of a robust, nonenzymatic electrochemical-sensing electrode modified with electrochemically reduced graphene oxide (ERGO) to detect PT residues in environmental samples (e.g., soil, water) as well as in vegetables and cereals. The ERGO sensor shows a significantly affected

• and straightforward responsive nature, high sensitivity, and selectivity leading to real-time detection [7]. A combination of a receptor, an analyte, and a transducer is made up to obtain an electrochemical sensor, in which the surface of the electrode induces redox characteristics via selective

Modeling a multiple-chain emeraldine gas sensor for NH₃ and NO₂ detection

• Hana Sustkova and
• Jan Voves

Beilstein J. Nanotechnol. 2022, 13, 721–729, doi:10.3762/bjnano.13.64

• numerically modeled for several adsorbed gas concentrations, several gas configurations, and different PANI molecule positions, including carrier hopping between them. The results are comparable to the experiment and show good properties for the application as gas sensor device for NH3 detection and rather

• good properties for NO2 detection. Keywords: ammonia; gas sensor; nitrogen dioxide; numerical computation; polyaniline; Introduction Polyaniline is a conducting polymer consisting of benzene rings connected by nitrogen units, which can be used in a wide spectrum of applications, for example, dyes for

• base has to be reduced by electrons (Figure 1). Emeraldine base or leucoemeraldine base salts of green color and with conductivity values of up to 400 S/m can be obtained through synthesis [4]. Recently, the polyaniline emeraldine salt has been studied for sensor applications for various gases because

Direct measurement of surface photovoltage by AC bias Kelvin probe force microscopy

• Masato Miyazaki,
• Yasuhiro Sugawara and
• Yan Jun Li

Beilstein J. Nanotechnol. 2022, 13, 712–720, doi:10.3762/bjnano.13.63

• was arranged in front of a photodetector of the OBD system to suppress the influence of the UV light on the deflection sensor. We used a commercial Ir-coated Si cantilever (NANOSENSORS, SD-T7L100) with a resonant frequency f0 of 913 kHz, a spring constant k of 650 N/m, and a quality factor Q of 7748

• density nFM is described as [74] where ntherm is the thermal noise density, ndetect is the detector noise density, nosc is the oscillator noise density, and nds is the deflection sensor noise density. The frequency noise δf measured with a bandwidth of B at a center of fm is described as When fm ≫ B, δf

Quantitative dynamic force microscopy with inclined tip oscillation

• Philipp Rahe,
• Daniel Heile,
• Reinhard Olbrich and
• Michael Reichling

Beilstein J. Nanotechnol. 2022, 13, 610–619, doi:10.3762/bjnano.13.53

• acquisition with an inclined tip sampling path requires modifications of the experimental procedures and data analysis protocols for force measurements to avoid systematic errors in the interpretation of force curve and imaging data. Results and Discussion Sensor positioning, sensor displacement, and tip

• be strictly parallel to Furthermore, we assume an infinitely stiff sensor in directions perpendicular to as well as a linear sensor response along Then, the static probe response follows Hooke’s law with k being the static sensor force constant [18]. In dynamic mode operation, the sensor is

• excited to periodic displacement q(t) = q(t + 1/fexc) along the q-axis at an excitation frequency fexc. To bring the tip in the desired range of interaction with the surface and to perform the movements required for imaging, force mapping, and taking force curves, the sensor is moved by coarse and fine

Detection and imaging of Hg(II) in vivo using glutathione-functionalized gold nanoparticles

• Gufeng Li,
• Shaoqing Li,
• Rui Wang,
• Min Yang,
• Lizhu Zhang,
• Yanli Zhang,
• Wenrong Yang and
• Hongbin Wang

Beilstein J. Nanotechnol. 2022, 13, 549–559, doi:10.3762/bjnano.13.46

• the fluorescent “ON” form. Keywords: cell imaging; fluorescence probes; glutathione; gold nanoparticles; mercury ions; rhodamine 6G derivatives; Introduction Metal nanoparticles have been widely used in the development and construction of sensor systems and drug carriers due to their excellent

Zinc oxide nanostructures for fluorescence and Raman signal enhancement: a review

• Ioana Marica,
• Fran Nekvapil,
• Maria Ștefan,
• Cosmin Farcău and
• Alexandra Falamaș

Beilstein J. Nanotechnol. 2022, 13, 472–490, doi:10.3762/bjnano.13.40

A non-enzymatic electrochemical hydrogen peroxide sensor based on copper oxide nanostructures

• Irena Mihailova,
• Vjaceslavs Gerbreders,
• Marina Krasovska,
• Eriks Sledevskis,
• Valdis Mizers,
• Andrejs Bulanovs and
• Andrejs Ogurcovs

Beilstein J. Nanotechnol. 2022, 13, 424–436, doi:10.3762/bjnano.13.35

• interfering substances, that is, ascorbic acid, uric acid, dopamine, NaCl, glucose, and acetaminophen, do not affect the electrochemical response. The real milk sample test showed a high recovery rate (more than 95%). According to the obtained results, this sensor is suitable for practical use for the

• qualitative detection of H2O2 in real samples, as well as for the quantitative determination of its concentration. Keywords: copper oxide; electrochemical sensor; hydrogen peroxide; nanostructures; Introduction Hydrogen peroxide, a strong oxidant and an essential intermediate product in many biomedical

• being horseradish peroxidase) [34][35][36], and detection is carried out through physicochemical processes of interaction between H2O2 and the enzyme. This type of sensor has high catalytic activity, sensitivity, and selectivity. However, enzyme sensors have a significant disadvantage, namely enzyme

A chemiresistive sensor array based on polyaniline nanocomposites and machine learning classification

• Jiri Kroutil,
• Alexandr Laposa,
• Ali Ahmad,
• Jan Voves,
• Vojtech Povolny,
• Ladislav Klimsa,
• Marina Davydova and
• Miroslav Husak

Beilstein J. Nanotechnol. 2022, 13, 411–423, doi:10.3762/bjnano.13.34

• 1999/2, 182 21 Prague, Czech Republic 10.3762/bjnano.13.34 Abstract The selective detection of ammonia (NH3), nitrogen dioxide (NO2), carbon oxides (CO2 and CO), acetone ((CH3)2CO), and toluene (C6H5CH3) is investigated by means of a gas sensor array based on polyaniline nanocomposites. The array

• data by principal component analysis to be a highly accurate method reach to 99% of the classification of six different gases. Keywords: feature extraction; gas sensor; pattern recognition; sensor array; Introduction The control and monitoring of toxic gaseous substances, such as ammonia, nitrogen

• . In most cases, the cross-sensitivity toward different chemical analytes is unavoidable, regardless of their oxidizing or reducing nature. Many authors have suggested a number of ways to overcome the drawbacks of cross-sensitivity/selectivity and reliability of the sensor arrays [3][4][5]. One

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

• switch to open. After the circuit conduction or charge disappears, the switch is pulled in again. By analyzing the electric field in the comb structure, He et al. [91] showed that the side electrode would generate a repulsive force without introducing a current. Pallay et al. [85] proposed a sensor

• -1583/aac0a8); © 2018 IOP Publishing. Reproduced with permission. All rights reserved. This content is not subject to CC BY 4.0. The structure of the NEM-PUF device. Figure 10 was redrawn from [79]. The structure of the sensor-switch system. Figure 11 was redrawn from [86]. The structure of the plate

Piezoelectric nanogenerator for bio-mechanical strain measurement

• Zafar Javed,
• Lybah Rafiq,
• Muhammad Anwaar Nazeer,
• Saqib Siddiqui,
• Muhammad Babar Ramzan,
• Muhammad Qamar Khan and
• Muhammad Salman Naeem

Beilstein J. Nanotechnol. 2022, 13, 192–200, doi:10.3762/bjnano.13.14

• as well. Under high dynamic strain more output voltage is generated than under low dynamic strain. The maximum current density shown by the device is 172.5 nA/cm2. The developed piezoelectric nanofiber sensor was then integrated into a knitted fabric through stitching to be used for angle measurement

• . With increasing bending angle, the output voltage increased. The promising results show that the textile-based piezoelectric sensor developed in this study has a great potential to be used as an angle measuring wearable device for the human body due to its high current density output and flexibility

• to develop sensors that were a wearable type of a goniometer. These sensors were then tested under static and dynamic conditions. For another application, researchers designed and developed a purely textile-based capacitive pressure sensor to be integrated and embedded into the garments to monitor

A photonic crystal material for the online detection of nonpolar hydrocarbon vapors

• Evgenii S. Bolshakov,
• Aleksander V. Ivanov,
• Andrei A. Kozlov,
• Anton S. Aksenov,
• Elena V. Isanbaeva,
• Sergei E. Kushnir,
• Aleksei D. Yapryntsev,
• Aleksander E. Baranchikov and
• Yury A. Zolotov

Beilstein J. Nanotechnol. 2022, 13, 127–136, doi:10.3762/bjnano.13.9

• array with a sensing matrix of polydimethylsiloxane, have been determined by using scanning electron microscopy and by the results of specular reflectance spectroscopy based on the Bragg–Snell law. A new approach has been proposed for the application of this sensor in chemical analysis for the

• qualitative detection of saturated vapors of volatile organic compounds due to configuration changes of the photonic bandgap, recorded by diffuse reflectance spectroscopy. The exposure of the sensor to aromatic (benzene, toluene and p-xylene) and aliphatic (n-pentane, n-heptane, n-octane and n-decane

• ) hydrocarbons has been analyzed. The reconstitution of spectral parameters of the sensor during the periodic detection of saturated vapors of toluene has been evaluated. Keywords: diffuse reflectance spectroscopy; photonic crystal sensor; stimuli-responsive materials; Introduction Photonic crystals (PhCs

Tin dioxide nanomaterial-based photocatalysts for nitrogen oxide oxidation: a review

• Viet Van Pham,
• Hong-Huy Tran,
• Thao Kim Truong and
• Thi Minh Cao

Beilstein J. Nanotechnol. 2022, 13, 96–113, doi:10.3762/bjnano.13.7

• morphologies will affect the properties of SnO2 regarding gas sensor activity and optical, electrical, and electrochemical properties [60][61][62][63]. The typical properties of SnO2 are significantly affected by the effective surface area of different nanomaterial morphologies [63][64][65]. Wang et al. [66

Topographic signatures and manipulations of Fe atoms, CO molecules and NaCl islands on superconducting Pb(111)

• Carl Drechsel,
• Philipp D’Astolfo,
• Jung-Ching Liu,
• Thilo Glatzel,
• Rémy Pawlak and
• Ernst Meyer

Beilstein J. Nanotechnol. 2022, 13, 1–9, doi:10.3762/bjnano.13.1

• temperature in the preparation chamber. Low-temperature scanning tunneling microscope The experiments were performed using a low-temperature STM/AFM microscope (T = 4.8 K) from Omicron GmbH in UHV (p ≈ 1 × 10−10 mbar) operated with Nanonis RC5 electronics. The sensor is a tuning fork sensor in a qPlus design

• [47] operated in the frequency-modulation mode (resonance frequency f0 ≈ 25 kHz, spring constant k ≈ 1800 N/m, quality factor Q ≈ 14000, and oscillation amplitude A ≈ 0.5 Å). The tip mounted to the qPlus sensor consists of a 25 μm-thick PtIr wire, shortened and sharpened with a focused ion beam. A

Measurement of polarization effects in dual-phase ceria-based oxygen permeation membranes using Kelvin probe force microscopy

• Kerstin Neuhaus,
• Christina Schmidt,
• Liudmila Fischer,
• Wilhelm Albert Meulenberg,
• Ke Ran,
• Joachim Mayer and
• Stefan Baumann

Beilstein J. Nanotechnol. 2021, 12, 1380–1391, doi:10.3762/bjnano.12.102

• permeation membrane, as oxygen sensor material, or for the use in solid oxide fuel cell components [1][5][6]. Apart from this, ceria is also widely employed as a catalyst in the middle- to low-temperature regime (20–400 °C) [7][8][9], making ceria-based dual-phase materials with a second electron-conductive

Two dynamic modes to streamline challenging atomic force microscopy measurements

• Alexei G. Temiryazev,
• Andrey V. Krayev and
• Marina P. Temiryazeva

Beilstein J. Nanotechnol. 2021, 12, 1226–1236, doi:10.3762/bjnano.12.90

• of scanning samples with high aspect ratio features. In AM-AFM, when scanning such samples at low oscillation amplitude, the lateral displacement velocity V must be kept very low to minimize error. When approaching a steep (high or deep) object, the sensor begins to touch it with the side of the

Morphology-driven gas sensing by fabricated fractals: A review

• Vishal Kamathe and
• Rupali Nagar

Beilstein J. Nanotechnol. 2021, 12, 1187–1208, doi:10.3762/bjnano.12.88

• to be possessing better gas sensing capabilities. Fab-fracs with these salient features will help in designing the commercial gas sensors with better performance. Keywords: adsorption sites; fabricated fractal; fractal dimension; gas sensor; morphology; pore network; recovery time; response time

• usage [5][6][7]. The objectives in gas sensing research are usually set to enhance the sensitivity (how the sensor responds to small changes when the gas environment around it changes), selectivity (if a sensor can still respond to a particular gas when many gases present), stability (how the sensor

• responds in a particular environment with time), the response time (time taken by a sensor to detect no gas to 90% of the gas when exposed to a gas environment), and recovery time (time taken by a sensor to fall to 10% of its baseline resistance value when the gas is removed from the environment

An overview of microneedle applications, materials, and fabrication methods

• Zahra Faraji Rad,
• Philip D. Prewett and
• Graham J. Davies

Beilstein J. Nanotechnol. 2021, 12, 1034–1046, doi:10.3762/bjnano.12.77

• in a study which integrated hollow silicon microneedles with a reservoir unit, a piezoelectric actuator system, and a flow sensor for real-time measurements of fluid dynamics [46]. In other research, much smaller microneedles – just 8 μm in height and 1 μm in diameter – were fabricated by DRIE for

Comprehensive review on ultrasound-responsive theranostic nanomaterials: mechanisms, structures and medical applications

• Sepand Tehrani Fateh,
• Lida Moradi,
• Elmira Kohan,
• Michael R. Hamblin and
• Amin Shiralizadeh Dezfuli

Beilstein J. Nanotechnol. 2021, 12, 808–862, doi:10.3762/bjnano.12.64

Reducing molecular simulation time for AFM images based on super-resolution methods

• Zhipeng Dou,
• Jianqiang Qian,
• Yingzi Li,
• Rui Lin,
• Jianhai Wang,
• Peng Cheng and
• Zeyu Xu

Beilstein J. Nanotechnol. 2021, 12, 775–785, doi:10.3762/bjnano.12.61

• and 0.1 Å vertical resolution [3]. Then, functionalizing the tip with closed-shell molecules and using a qPlus force sensor enabled the imaging of the internal structure of the molecules [4][5][6][7], resolving features of weak-bonded molecules [8][9][10][11][12], and measurement of bond-order

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