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This brief review covers the thermoelectric properties of one-dimensional materials, such as nanowires and nanotubes. The highly localised peaks of the electronic density of states near the Fermi levels of these nanostructured materials improve the Seebeck coefficient. Moreover, quantum confinement leads to discrete energy levels and a modified density of states, potentially enhancing electrical conductivity. These electronic effects, coupled with the dominance of Umklapp phonon scattering, which reduces thermal conductivity in one-dimensional materials, can achieve unprecedented thermoelectric efficiency not seen in two-dimensional or bulk materials. Notable advancements include carbon and silicon nanotubes and Bi3Te2, Bi, ZnO, SiC, and Si1−xGex nanowires with significantly reduced thermal conductivity and increased ZT. In all these nanowires and nanotubes, efficiency is explored as a function of the diameter. Among these nanomaterials, carbon nanotubes offer mechanical flexibility and improved thermoelectric performance. Although carbon nanotubes theoretically have high thermal conductivity, the improvement of their Seebeck coefficient due to their low-dimensional structure can compensate for it. Regarding flexibility, economic criteria, ease of fabrication, and weight, carbon nanotubes could be a promising candidate for thermoelectric power generation. [ABSTRACT FROM AUTHOR]

We conducted a simple solution-based method to fabricate Bi2S3 nanowire thin film solar cells by spin coating with varying sulfur-to-bismuth ratios. Spherical nanoparticles were observed in the thin film with low-concentration sulfur solution, with these nanoparticles gradually changing to nanorods. Finally, nanowires of Bi2S3 were observed in the thin film with a high sulfur concentration in solution. The band gap gradually decreased with the increase in sulfur concentration. The solar cell performance was significantly improved with the nanowire structure. During film fabrication, sulfur vacancy defects appeared primarily because of high annealing temperatures. These defects were somewhat reduced by the high concentration of sulfur in the solution, supported by the energy-dispersive x-ray spectroscopy (EDS) results. The elemental chemical composition of Bi2S3 material showed an increase in the sulfur-to-bismuth ratio, reaching saturation at almost 0.9. In this work, we systematically observed the effect on the optical properties, surface morphology, and photovoltaic properties by changing the concentration of sulfur in the precursor. The nanowire structure with a high concentration of sulfur in the solution is a promising way to improve the Bi2S3 thin film solar cell. [ABSTRACT FROM AUTHOR]

In line with the fast progress of nanotechnology, it is important to have compact semiconductor devices to function and offer the best results at various technology nodes. Gate-All-Around (GAA) Nanowire Field Effect Transistor (FET) is one of the most promising structures. Nanowire having an 8 nm channel length with the same source and drain doping concentration is used for this analysis. This work uses the sp3d5s* tight-binding model for comparative analysis of Nanowire FET. The non-equilibrium Green's function (NEGF) approach is used for this simulation. The comparative analysis is made by changing the diameter of the nanowire, crystal orientation, and oxide thickness for different channel materials Si and GaAs. The results show that the GAA Si Nanowire is superior with a high current on-off (Ion/off) ratio of 1011 having a diameter of 1.5 nm. The nanowire with a small diameter shows the best result in terms of On-current (Ion) and Off-current (Ioff). For crystal orientation x[100] which is along the transport of carriers in nanowires, the results obtained are very good as compared to other orientations. The hydrostatic strain has been analyzed. The change in the current on-off ratio with hydrostatic strain makes them a leading option for future sensors. [ABSTRACT FROM AUTHOR]

This computational research study will compare the specific charge capacity (SCC) between lithium ions inserted into crystallized silicon (c-Si) nanowires with that of sodium ions inserted into amorphous silicon (a-Si) nanowires. It will be demonstrated that the potential energy V(r) within a lithium–silicon nanowire supports a coherent energy state model with discrete electron particles, while the potential energy of a sodium–silicon nanowire will be discovered to be essentially zero, and, thus, the electron current that travels through a sodiated silicon nanowire will be modeled as a free electron with wave-like characteristics. This is due to the vast differences in the electric fields of lithiated and sodiated silicon nanowires, where the electric fields are of the order of 10 10 V/m and 10 − 15 V/m, respectively. The main reason for the great disparity in electric fields is the presence of optical amplification within lithium ions and the absence of this process within sodium ions. It will be shown that optical amplification develops coherent optical interactions, which is the primary reason for the surge of specific charge capacity in the lithiated silicon nanowire. Conversely, the lack of optical amplification is the reason for the incoherent optical interactions within sodium ions, which is the reason for the low presence of SCC in sodiated silicon nanowires. [ABSTRACT FROM AUTHOR]

The monolithic integration of bottom‐up nanowires into devices requires rational growth of aligned nanowires. Of the proposed aligned growth methods, few are sufficiently general to be applicable to diverse materials and substrates. In this work, oriented poly(tetrafluoroethylene) (PTFE) grooves with nanoscale depth and width are transferred onto different substrates through a simple directional mechanical friction. This friction is achieved in a few seconds by a program‐driven handwriting machine. Various organic molecules (e.g., Alq3, NiPc, CoPc, CuPc, F16CuPc) are therefore assembled into oriented crystalline nanowires on the surface of Si, Si/SiO2, and glass. The self‐alignment of these nanowires enables a scalable device fabrication directly on growth substrates, eliminating structural damage and contamination during post‐growth alignment. For example, using the aligned F16CuPc nanowires on PTFE‐coated Si/SiO2 wafers, back‐gate field‐effect phototransistors are fabricated in a scalable manner by directly depositing an array of micro‐sized electrodes. Statistical results show that these phototransistors operate in n‐type enhancement mode with thresholds of a few volts. In addition, they exhibit fast photoresponse on the order of tens of milliseconds and long‐term stability in the vis–NIR spectrum. The generality of this guided nanowire growth and resulting monolithic devices offer new opportunities for the monolithic integration of nanowire‐based devices. [ABSTRACT FROM AUTHOR]

Metal‐halide perovskites (MHPs) are promising as active optoelectronic materials for a diverse range of devices. Anion exchange is a post‐growth modification of MHP materials that allows tuning of the band gap and crystal structure by exposure to alternative halides, normally using solution methods. Here, low temperature gas‐phase anion exchange for the conversion of CsPbBr3 nanowires (NW) into CsPb(Br1−xClx) NWs using two media, fuming HCl and Cl2 gas, is systematically investigated. It is found that both methods can be used to tune the composition in the full range with excellent control. While fuming HCl is the simplest process, Cl2 gives similar results with no surface damage and better process control. Based on a simple solid diffusion model, an average diffusivity of 1.4 × 10−12 cm2s−1 is extracted for Cl‐anions inside CsPbBr3. By combining the Cl2 exchange process with electron‐beam lithography patterning, heterojunction NWs with varying halide compositions are produced, including complex barcode‐like NWs with segment lengths as short as 500 nm. Designed heterostructures provide an important basis for optoelectronic device applications of MHPs, and gas‐phase anion exchange should be suitable for any MHP morphology. [ABSTRACT FROM AUTHOR]

Analytical expressions for spontaneous emission probability in the vicinity of nanowire for the emitter oriented in axial, radial and azimuthal direction in respect to the nanowire axis, has been obtained. Directionality of emission and probability of emission have been calculated for various positions of emitter. Enhancement of the spontaneous emission probability by one order of magnitude, and formation of the sharp directionality diagram has been demonstrated. [ABSTRACT FROM AUTHOR]

In this paper, multi-channel nanowire (NW) performance is significantly improved by symmetric and asymmetric spacer length optimization. Device performance metrics including ON current (ION), OFF current (IOFF), and switching ratio (ION/IOFF) are improved by careful optimization of spacer length. It is observed that the NW FET exhibits the best performance with symmetric spacer lengths of source-side spacer length (LS) and drain-side spacer length (LD) of 15 nm, whereas it is observed to be LS = 15 nm and LD = 25 nm for asymmetric spacer lengths. The device exhibits the highest ION with the symmetric spacer, ensuring high-performance applications, and the lowest IOFF with the asymmetric spacer, ensuring low-power applications. In addition, an analog/RF performance comparison is made with symmetric and asymmetric spacers, and the circuit performance results are extracted using the Cadence tool through the Verilog-A interface by utilizing a lookup table approach. The common source (CS) amplifier and resistive load inverter are investigated and gain is determined. The CS amplifier exhibits higher gain (VOUT/VIN) with the asymmetric spacer. Further, a resistive load inverter is designed and demonstrated to realize optimal performance by varying the resistive load (RL) and operating voltage (VDD). The symmetric spacer exhibits better voltage transfer characteristics with RL variations. [ABSTRACT FROM AUTHOR]

The metal‒semiconductor heterojunction is imperative for the realization of electrically driven nanolasers for chip‐level platforms. Progress in developing such nanolasers has hitherto rarely been realized, however, because of their complexity in heterojunction fabrication and the need to use noble metals that are incompatible with microelectronic manufacturing. Most plasmonic nanolasers lase either above a high threshold (101‒103 MW cm−2) or at a cryogenic temperature, and lasing is possible only after they are removed from the substrate to avoid the large ohmic loss and the low modal reflectivity, making monolithic fabrication impossible. Here, for the first time, record‐low‐threshold, room‐temperature ultraviolet (UV) lasing of plasmon‐coupled core‒shell nanowires that are directly grown on silicon is demonstrated. The naturally formed core‒shell metal‒semiconductor heterostructure of the nanowires leads to a 100‐fold improvement in growth density over previous results. This unprecedentedly high nanowire density creates intense plasmonic resonance, which is outcoupled to the resonant Fabry‒Pérot microcavity. By boosting the emission strength by a factor of 100, the hybrid photonic‒plasmonic system successfully facilitates a record‐low laser threshold of 12 kW cm−2 with a spontaneous emission coupling factor as high as ≈0.32 in the 340‒360 nm range. Such architecture is simple and cost‐competitive for future UV sources in silicon integration. [ABSTRACT FROM AUTHOR]

Micro/nano-textured Si wafers manufactured using metal-assisted chemical etching (MACE) have been the focus of several studies, but the mechanism of bubble generation during the MACE process affecting textured surfaces has rarely been reported. This study investigated the bubble effect due to the different placement patterns of the Si wafer (face-up, stirred face-down, and face-down). The results indicated that the placement pattern of the Si wafer notably influences the uniformity of outward appearance. At 2 h of etching, the outward appearance uniformity of face-up etching was more homogeneous than that of stirred face-down and face-down patterns, and the Si nanowires (SiNWs) processed through face-up etching were longer (41 μm) than those subjected to stirred face-down etching (36 μm) and face-down etching (32 μm). Therefore, the placement pattern of Si wafer can affect the uniformity and properties of SiNWs because of bubbles trapped inside cavities or between SiNWs. [ABSTRACT FROM AUTHOR]

Carbon-doped silicon (Si:C) thin films with C concentrations of 0.60% and 0.83% were fabricated into nanowires, and the lattice strain relaxation with shrinking the nanowire width, W, was evaluated in detail by x-ray reciprocal lattice space mapping (RSM) measurements. The obtained RSM profiles showed a right-downward distribution. From the RSM profiles, we considered that the lattice relaxation of the Si:C nanowires progressed slowly from the nanowires/substrate interfaces to the nanowire top surfaces. Then, we assumed the lattice strain of the Si:C thin films to be 100% and derived the average lattice strain relaxation of the Si:C nanowires from the RSM profiles. To derive the lattice relaxation, we summed the RSM profiles in the qx or qz directions, respectively, and calculated the average in-plane and out-of-plane lattice parameters. The obtained average lattice strain relaxation became larger with shrinking W, and progressed rapidly at W = 200 nm. Thus, we considered that the large strain relaxation occurs in the region of approximately 100 nm from the edge of the nanowires. In addition, the lattice strain relaxation was smaller for Si:C nanowires fabricated with their long side along the [100] direction than for Si:C nanowires along the [110] direction. We considered this difference of strain relaxation might be due to the crystallographic orientation dependence of Young's modulus. [ABSTRACT FROM AUTHOR]

We used capacitance–voltage (C–V), conductance–voltage (G–V), and noise measurements to examine the carrier trap mechanisms at the surface/core of an AlGaN/GaN nanowire wrap-gate transistor (WGT). When the frequency is increased, the predicted surface trap density promptly drops, with values ranging from 9.1 × 1013 eV−1∙cm−2 at 1 kHz to 1.2 × 1011 eV−1∙cm−2 at 1 MHz. The power spectral density exhibits 1/f-noise behavior in the barrier accumulation area and rises with gate bias, according to the 1/f-noise features. At lower frequencies, the device exhibits 1/f-noise behavior, while beyond 1 kHz, it exhibits 1/f2-noise behavior. Additionally, when the fabricated device governs in the deep-subthreshold regime, the cutoff frequency for the 1/f2-noise features moves to the subordinated frequency (~102 Hz) side. [ABSTRACT FROM AUTHOR]

The thermal conductivity of tortuous silicon nanowires with constant cross section at room temperature was investigated in use of full-spectrum Monte-Carlo simulations. Various geometric features that can be possibly used to describe the tortuosity of the nanowires were studied and their relationships with the thermal conductivity were explored. Comparison of simulation results with experimental data shows similar magnitudes and variation trend of the thermal conductivity against the nanowire hydraulic diameter. The more tortuous, the smaller the thermal conductivity is. Among all, data collapse is best when shown against the surface-to-volume ratio and the correlation length of the surface roughness does not affect the thermal conductivity at all. By taking the surface-to-volume ratio into account for the boundary scattering rate, which also depends on the phonon frequency indirectly through the phonon group velocity, we are able to obtain satisfactory predictions based on a linear spectral model, not only about the thermal conductivity but also about the spectral heat flux density distribution. The model also shows that the relative reduction caused by tortuosity decreases with increasing frequency. For highly tortuous nanowires of diameter 22 nm, simply increasing the tortuosity is sufficient to obtain simulated thermal conductivities that are smaller than the experimentally measured value. [ABSTRACT FROM AUTHOR]

This research work uses sp3d5s* tight-binding models to design and analyze the structural properties of group IV and III-V oriented, rectangular Silicon (Si) and Gallium Arsenide (GaAs) Nanowires (NWs). The electrical characteristics of the NWs, which are shielded with Lanthanum Oxide (La2O3) material and the orientation with z [001] using the Non-Equilibrium Green Function (NEGF) method, have been analyzed. The electrical characteristics and the parameters for the multi-gate nanowires have been realized. A nanowire comprises a heavily doped n+ donor source and drains doping and n-donor doping at the channel. The specified nanowire has a gate length and channel length of 15 nm each, a source-drain device length LSD = 35 nm, with La2O3 as 1 nm (gate dielectric oxide) each on the top and bottom of the core material (Si/GaAs). The Gate-All-Around (GAA) Si NW is superior with a high (ION/IOFF ratio) of 1.06 × 109, and a low leakage current, or OFF current (IOFF), of 3.84 × 10−14 A. The measured values of the mid-channel conduction band energy (Ec) and charge carrier density (ρ) at VG = VD = 0.5 V are −0.309 eV and 6.24 × 1023 C/cm3, respectively. The nanowires with hydrostatic strain have been determined by electrostatic integrity and increased mobility, making them a leading solution for upcoming technological nodes. The transverse dimensions of the rectangular nanowires with similar energy levels are realized and comparisons between Si and GaAs NWs have been performed. [ABSTRACT FROM AUTHOR]

Determining how to improve the non-uniformity of arrayed waveguide grating (AWG) is of great significance for dense wavelength division multiplexing (DWDM) systems. In this work, a silicon nanowire-assisted AWG structure is proposed, which can achieve high uniformity with a low insertion loss. The article compares the effect of nanowire number and shape on uniformity and insertion loss, finding that double nanowires provide the best performance. Double nanowires with a width of 230 nm and length of 3.5 μm can consist of a slot configuration between arrayed waveguides, both connecting to the star coupler and spacing 165 nm from the waveguides. Compared with conventional 8- and 16-channel AWGs with channel spacing of 200 GHz, the non-uniformity of the presented structure can be improved from 1.09 and 1.6 dB to 0.24 and 0.63 dB, respectively. The overall footprint of the device would remain identical, which is 276 × 299 or 258 × 303 μm2 for the 8- or 16-channel AWG. The present high uniformity design is simple and easy to fabricate without any additional insertion loss, which is expected to be widely applied in the highly integrated DWDM systems. [ABSTRACT FROM AUTHOR]

Ovarian cancer is a gynecological cancer characterized by a high mortality rate and tumor heterogeneity. Its early detection and primary prophylaxis are difficult to perform. Detecting biomarkers for ovarian cancer plays a pivotal role in therapy effectiveness and affects patients' survival. This study demonstrates the detection of microRNAs (miRNAs), which were reported to be associated with ovarian cancer tumorigenesis, with a nanowire biosensor based on silicon-on-insulator structures (SOI-NW biosensor). The advantages of the method proposed for miRNA detection using the SOI-NW biosensor are as follows: (1) no need for additional labeling or amplification reaction during sample preparation, and (2) real-time detection of target biomolecules. The detecting component of the biosensor is a chip with an array of 3 µm wide, 10 µm long silicon nanowires on its surface. The SOI-NW chip was fabricated using the "top-down" method, which is compatible with large-scale CMOS technology. Oligonucleotide probes (oDNA probes) carrying sequences complementary to the target miRNAs were covalently immobilized on the nanowire surface to ensure high-sensitivity biospecific sensing of the target biomolecules. The study involved two experimental series. Detection of model DNA oligonucleotides being synthetic analogs of the target miRNAs was carried out to assess the method's sensitivity. The lowest concentration of the target oligonucleotides detectable in buffer solution was 1.1 × 10−16 M. In the second experimental series, detection of miRNAs (miRNA-21, miRNA-141, and miRNA-200a) isolated from blood plasma samples collected from patients having a verified diagnosis of ovarian cancer was performed. The results of our present study represent a step towards the development of novel highly sensitive diagnostic systems for the early revelation of ovarian cancer in women. [ABSTRACT FROM AUTHOR]

In this paper, a novel low power consumption device based on a dopingless gate-all-around nanowire tunnel field effect transistor (TFET) with negative capacitance (NC) effect is proposed. NC is a robust approach in solving the bottleneck issues encountered by devices operating in nanoscale domains. Additionally, the threshold voltage (V T) and subthreshold swing (SS) are dropped significantly to less than 60 mV/decade. Negative capacitance makes a significant contribution to the device’s performance by lowering the operating voltage for low-power applications. To calculate the optimum bias, the Landauâ€"Khalatnikov (Lâ€"K) equation was used. To evaluate the influence of NC, the ferroelectric (FE) material PZT (lead zirconate titanate), which has perovskite properties, was used as a gate insulator. Thus, the gate-all-around dopingless nanowire TFET (GAA DL NW TFET) device structure is reconfigured into GAA NC DL NW TFET. PZT has an appropriate polarization rate, high dielectric capacitance, and a high degree of reliability. To achieve an SS lower than 60 mV/decade at lower V T, effective tuning of the FE thickness is critical to avoid hysteresis, which enhances the overall performance of the proposed device. The aggressively scaled device has the problem of fabrication complexity and its associated cost that is addressed with the help of the dopingless technique to the nanowire-based TFET. The enhancement of the ON-current with an improved steep SS was addressed. With the application of the NC technique, the proposed device showcased an improved 4 µ A µ mâˆ'1 of I ON, and 1012 of current ratio. Additionally, the influence of the variation in FE thickness on the performance parameters is examined. The proposed device structure operates at a minimum operating voltage, making it an ideal choice for low-power voltage applications. [ABSTRACT FROM AUTHOR]

A nanowire junctionless FET biosensor has been modelled with COMSOL Multiphysics. The high sensitivity of the device in depletion regime was observed. The sensitivity dependence on variations of species concentration in analyte surrounding the nanowire has been studied. It has been demonstrated that the thinner is the nanowire, the higher is the sensitivity and even a single molecule affects the drain current. The model is useful for sensor optimization. [ABSTRACT FROM AUTHOR]

Near-infrared detection is widely used for nondestructive and non-contact inspections in various areas, including thermography, environmental and chemical analysis as well as food and medical diagnoses. Common room temperature bolometer-type infrared sensors are based on architectures in the ÎĽ m range, limiting miniaturization for future highly integrated ‘More than Moore’ concepts. In this work, we present a first principle study on a highly scalable and CMOS compatible bolometer-type detector utilizing Ge nanowires as the thermal sensitive element. For this approach, we implemented the Ge nanowires on top of a low thermal conducting and highly absorptive membrane as a near infrared (IR) sensor element. We adopted a freestanding membrane coated with an impedance matched platinum absorber demonstrating wavelength independent absorptivity of 50% in the near to mid IR regime. The electrical characteristics of the device were measured depending on temperature and biasing conditions. A strong dependence of the resistance on the temperature was shown with a maximum temperature coefficient of resistance of âˆ'0.07 Kâˆ'1 at T  = 100 K. Heat transport simulations using COMSOL were used to optimize the responsivity and temporal response, which are in good agreement with the experimental results. Further, lock-in measurements were used to benchmark the bolometer device at room temperature with respect to detectivity and noise equivalent power. Finally, we demonstrated that by operating the bolometer with a network of parallel nanowires, both detectivity and noise equivalent power can be effectively improved. [ABSTRACT FROM AUTHOR]

Control of surface defects and impurity doping are important keys to realizing devices that use semiconductor nanowires (NWs). As a structure capable of suppressing impurity scattering, p-Si/i (intrinsic)-Ge coreâ€"shell NWs with radial heterojunctions inside the NWs were formed. When forming NWs using a top-down method, the positions of the NWs can be controlled, but their surface is damaged. When heat treatment for repairing surface damage is performed, the surface roughness of the NWs closely depends on the kind of atmospheric gas. Oxidation and chemical etching prior to shell formation removes the surface damaged layer on p-SiNWs and simultaneously achieves a reduction in the diameter of the NWs. Finally, hole gas accumulation, which is important for suppressing impurity scattering, can be observed in the i-Ge layers of p-Si/i-Ge coreâ€"shell NWs. [ABSTRACT FROM AUTHOR]

We demonstrate a bottom-up process for programming the deposition of coaxial thin films aligned to the underlying dopant profile of semiconductor nanowires. Our process synergistically combines three distinct methodsâ€"vaporâ€"liquidâ€"solid nanowire growth, selective coaxial lithography via etching of surfaces (SCALES), and area-selective atomic layer deposition (AS-ALD)â€"into a cohesive whole. Here, we study ZrO2 on Si nanowires as a model system. Si nanowires are first grown with an axially modulated n-Si/i-Si dopant profile. SCALES then yields coaxial poly(methyl methacrylate) (PMMA) masks on the n-Si regions. Subsequent AS-ALD of ZrO2 occurs on the exposed i-Si regions and not on those masked by PMMA. We show the spatial relationship between nanowire dopant profile, PMMA masks, and ZrO2 films, confirming the programmability of the process. The nanoscale resolution of our process coupled with the plethora of available AS-ALD chemistries promises a range of future opportunities to generate structurally complex nanoscale materials and electronic devices using entirely bottom-up methods. [ABSTRACT FROM AUTHOR]

A comprehensive computational study of gate-all-around (GAA) devices with 3-D stacked silicon nanosheets (also known as nanoribbons or nanowires) is presented in this article. Technology development guidelines are provided for low-power applications in 5-nm CMOS technology node and beyond. The 3-D stacked nanosheet devices lower the subthreshold swing, drain-induced barrier-lowering, and subthreshold leakage current by up to 20.75%, 38.89%, and 88.53%, respectively, when compared to a silicon-on-insulator (SOI) FinFET with 5-nm physical gate length and identical silicon area at ${V}_{\text {DD}} = {0.6}$ V and ${T} = {80}\,\,^{\circ }\text{C}$. The voltage gain of a minimum-sized CMOS inverter is increased by up to 157% with the 3-D stacked nanosheet devices, thereby providing robust operation with wider noise margins when compared to the SOI-FinFET technology. Furthermore, by scaling the supply voltage to 0.49 V, the energy consumption of a CMOS inverter is reduced by 53.81% with the GAA 3-D stacked nanosheet devices while providing similar output transition speed when compared to the SOI-FinFET technology. [ABSTRACT FROM AUTHOR]

An ab initio core-shell model is proposed to evaluate the surface effect in bending nanowires, in which the elastic modulus depends on the surface relaxation and deformation induced by external loading. By using first-principles calculations based on the density functional theory (DFT), the surface and bulk properties are calculated for Ag, Pb, and Si nanowires. The obtained theoretical predictions of the effective Young's modulus of nanowires agree well with the experimental data, which shows that the fixed-fixed nanowire is stiffened and the cantilevered nanowire is softened as the characteristic size of the cross section decreases. Furthermore, the contrastive analysis on the two kinds of nanowires demonstrates that increasing the nanowire aspect ratio would enhance the surface effect. The present results could be helpful for understanding the size effect in nanowires and designing nanobeam-based devices in nanoelectromechanical systems (NEMSs). [ABSTRACT FROM AUTHOR]

The nanowire gate-all-around structure with the ultimate channel electrostatic integrity exhibits the best immunity to short channel effects and improved scaling capability compared with other multigate structures. In this article, both the tunneling current and capacitance models are developed simultaneously for nanowire tunneling field-effect transistors (FETs). Based on the same surface potential model, the developed current model and capacitance model share the common parameters and therefore can be easily integrated as a complete model for circuit-level simulations. Moreover, there is no iterative process involved during the model derivation indicating the models would be efficient for circuit simulations. The proposed models are also implemented into a circuit simulator with SPICE net-list to simulate the inverter, NAND, and NOR gates. Correct circuit behaviors obtained validate the model compatibility with the SPICE platform and usefulness for the further investigation of nanowire-based tunnel FET (TFET) circuits. [ABSTRACT FROM AUTHOR]

In this paper, conventional charge-plasma nanowire tunnel field-effect transistor (CP-NWTFET) has been applied by gate stacking and SiGe sourced to design the proposed Si0.55Ge0.45 sourced nanowire tunnel field-effect transistor based on charge plasma and gate stack (SiGe-GS-CP-NWTFET) to enhance electrical characteristics. Comparison of drain current (Id), transconductance (gm), second-order transconductance (gm2), third-order transconductance (gm3), and transconductance generation factor are analysed between conventional CP-NWTFET and SiGe-GS-CP-NWTFET. The results demonstrate that the proposed SiGe-GS-CP-NWTFET device possesses a larger drive current, transconductance, and transconductance factor those of the conventional device. Further, the impact of temperature on various parameters such as subthreshold slope (SS), threshold voltage (Vth), Ion, Ioff, and Ion/Ioff ratio is analysed for the proposed SiGe-GS-CP-NWTFET device. With an increase in temperature, both ON-current and OFF-current upsurge which results in a decrease in the current ratio. A lower subthreshold slope is observed for lower temperature, whereas a lower threshold voltage is observed for higher temperature. The parameters, like the electric field, potential, and energy band diagram which help in understanding the physics of the device, are also analysed for various temperatures. The impact of mole fraction(x) of Ge in SiGe on SS, Vth, Ion, Ioff, and Ion/Ioff ratio is also analysed for the proposed device. Ion, Ioff increase with mole fraction, whereas Vth decreases with temperature. The current ratio and SS are found to be better for the mole fraction of x = 0.45. The improved performance compared to the conventional CP-NWTFET is attributed to the superiority of the proposed SiGe-GS-CP-NWTFET device. [ABSTRACT FROM AUTHOR]

Four sources of variability, metal grain granularity (MGG), line-edge roughness (LER), gate-edge roughness (GER), and random discrete dopants (RDD), affecting the performance of state-of-the-art FinFET, nanosheet (NS), and nanowire (NW) FETs, are analysed via our in-house 3D finite-element drift-diffusion/Monte Carlo simulator that includes 2D Schrödinger equation quantum corrections. The MGG and LER are the sources of variability that influence device performance of the three multi-gate architectures the most. The FinFET and the NS FET are similarly affected by the MGG variations with threshold voltage and on-current standard deviations significantly lower (at least 20 %) than those of the NW FET. The LER variability has a negligible influence in the NS FET performance with $\sigma ~{V}_{T}$ values around 12 and 42 times lower than those of the FinFET and the NW FET. The three architectures are equally affected by the RDD ($\sigma {V}_{T}$ = 8 mV) and minimally influenced by the GER ($\sigma {V}_{T} \approx 4$ mV). The variability of NS FETs makes them strong candidates to replace FinFETs. [ABSTRACT FROM AUTHOR]

We investigate the operation modes of a dual-gate reconfigurable field-effect transistor (RFET). To this end, dual-gate silicon-nanowire FETs are fabricated based on anisotropic wet etching of silicon and nickel silicidation yielding silicide-nanowire Schottky junctions at source and drain. We compare the program gate at source (PGAS) with the more usual program gate at drain (PGAD) operation mode. While in PGAD mode, ambipolar operation is suppressed, switching is deteriorated due to the injection through a Schottky barrier. Operating the RFET in PGAS mode yields a switching behavior close to a conventional MOSFET. This, however, needs to be traded off against strongly nonlinear output characteristics for small bias voltages. Our measurement results are supported by transport simulations employing a nonequilibrium Green’s function approach. [ABSTRACT FROM AUTHOR]

In this study, p-type Pi-gate (PG) poly-Si nanowire channel junctionless accumulation-mode (JAM) field-effect transistors (FETs) were successfully fabricated and their reliability was investigated. The reliability of these PG JAM FETs was found to be dependent on the effective channel doping concentration (Nch,eff). Through a negative gate bias stress (NGBS) test, we found that degradation in the average subthreshold swing (A.S.S.) and shift in the threshold voltage (VTH) increases as the Nch,eff of the PG JAM FETs decreases. Furthermore, the PG JAM FETs with a lower Nch,eff show the more severe rate of deterioration in the transconductance (Gm) and ON current (ION). By increasing Nch,eff to reduce the electric field (E-field) on the gate oxide and tune the carrier transport mechanism in the poly-Si nanowire channel, a better immunity against the NGBS test in the p-type PG JAM FETs can be achieved under a gate overdrive voltage (VGOD = VG – VTH = −3.5 V) to perform the NGBS test. [ABSTRACT FROM AUTHOR]

This research paper explains the effect of the dimensions of Gate-all-around Si nanowire tunneling field effect transistor (GAA Si-NW TFET) on ON/OFF current ratio, drain induces barrier lowering (DIBL), sub-threshold swing (SS), and threshold voltage (VT). These parameters are critical factors of the characteristics of tunnel field effect transistors. The Silvaco TCAD has been used to study the electrical characteristics of Si-NW TFET. Output (gate voltage-drain current) characteristics with channel dimensions were simulated. Results show that 50nm long nanowires with 9nm-18nm diameter and 3nm oxide thickness tend to have the best nanowire tunnel field effect transistor (Si-NW TFET) characteristics. [ABSTRACT FROM AUTHOR]

Understanding the correlation between exposed surfaces and performances of controlled nanocatalysts can aid effective strategies to enhance electrocatalysis, but this is as yet unexplored for the nitrogen reduction reaction (NRR). Here, we first report controlled synthesis of well-defined Pt3Fe nanocrystals with tunable morphologies (nanocube, nanorod and nanowire) as ideal model electrocatalysts for investigating the NRR on different exposed facets. The detailed electrocatalytic studies reveal that the Pt3Fe nanocrystals exhibit shape-dependent NRR electrocatalysis. The optimized Pt3Fe nanowires bounded with high-index facets exhibit excellent selectivity (no N2H4 is detected), high activity with NH3 yield of 18.3 μg h−1 mg−1cat (0.52 μg h−1 cm−2ECSA; ECSA: electrochemical active surface area) and Faraday efficiency of 7.3% at −0.05 V versus reversible hydrogen electrode, outperforming the {200} facet-enclosed Pt3Fe nanocubes and {111} facet-enclosed Pt3Fe nanorods. They also show good stability with negligible activity change after five cycles. Density functional theory calculations reveal that, with high-indexed facet engineering, the Fe-3d band is an efficient d-d coupling correlation center for boosting the Pt 5d-electronic exchange and transfer activities towards the NRR. [ABSTRACT FROM AUTHOR]

The findings from the time-of-flight (TOF) experiment for strained silicon nanowires are reported in this article, in combination with numerical simulations demonstrating new physical features involved in the quasi-quantum regime. The drift velocity of valence holes is demonstrated to exceed greatly that of conduction electrons. These experimental data are accurately reproduced by our simulations, revealing a dramatic reduction in the hole’s effective mass as well as a significant extension of the mean-free time between two consecutive random scattering events due to combined effects of both quantum confinement and biaxial strain. Many-body theory is further introduced for calculating elastic-scattering rate of impurities with the inclusion of static screening under the random-phase approximation. Dark current, photo-current and photoluminescence spectra are all measured in our experiments, in addition to direct TOF experiment by employing a Ti-sapphire mode-locked femtosecond laser, and their data are fully analyzed and physically explained by using both simulations and many-body theory. Our observation that the Einstein’s relation does not hold true for 1-D transport under a strong electric field is supported by a quantum-statistical calculation. Our discovery with a very large hole mobility is expected to play a key role in establishing a much more straight-forward technical path towards high-performance CMOS and radio-frequency amplifiers than current ones. [ABSTRACT FROM AUTHOR]

The commercialization of rechargeable Li metal batteries is hindered by dendrite growth and volumetric variation. Herein, we report a Li-rich dual-phase Li-Cu alloy with built-in 3D conductive skeleton to replace conventional planar Li anode. The Li-Cu alloy is simply prepared by fusion of Li and Cu metals at a relatively low-temperature of 500 °C, followed by a cooling process where phase-segregation leads to metallic Li phase distributed in the network of LiCu x solid solution phase. Different from the common Li alloy, the electrochemical alloying reaction between Li and Cu metals is not observed. Therefore, the lithiophilic LiCu x nanowires guides conformal plating of Li and the porous framework provides superior dimensional stability for the anode. This unique ferroconcrete-like structure of Li-Cu alloy enables dendrite-free Li plating for an expanded cycling lifetime. Constructing a new type of Li alloy with in situ formed electrochemically inactive framework is a promising and easily scaled-up strategy toward practical application of Li metal anodes. [ABSTRACT FROM AUTHOR]

In this study, we present a statistically accurate model to predict the threshold-voltage variability (σVth) efficiently for three-dimensional (3D) vertically stacked silicon (Si) gate-all-around (GAA) nanowire (NW) n-MOSFETs with multi-channels. The statistical results indicate that the σVth decreases exponentially by increasing metal grain number (MGN), which is unitless. Additionally, the magnitude of σVth was calculated for various MGNs, which joins the normality test with Anderson–Darling test. Therefore, the model with MGN can be implemented by nonlinear regression with a regression coefficient of approximately one. From this model and the perspective of process, more 3D vertically stacked channels can reduce the value and sensitivity of σVth. This study provides useful information from statistics to explain the experiment results for 3D vertically stacked Si GAA NW n-MOSFETs with multi-channels. [ABSTRACT FROM AUTHOR]

In nowadays technology, the primary memory structure widely used in many digital circuit applications is a six transistor (6T) Static Random Access Memory (SRAM) bit cell. The main reason for minimizing memory bit cell to nanodimensions is to provide the SRAM integrated circuits (ICs) with the possible largest memory size per one chip, and the main unit in 6T SRAM bit cell is the MOSFET. One of the new MOSFET structures that overcome conventional MOSFET structure problems under minimization towards nanodimension is the silicon nanowire transistor (SiNWT). This study is the first to explore and optimize the nanowire ratio of driver to load (KD/KL) for a six n-channel SiNWT-based SRAM bit cell. The MuGFET simulation tool has been used to calculate the output characteristics of each transistor individually, and then these characteristics are implemented in the MATLAB software to produce the final static butterfly and current characteristics of nanowire 6T-SRAM bit cell. The demonstration of the driver to load transistors’ nanowires ratio optimizations of nanoscale n-type SiNWT-based SRAM bit cell has been discussed. In this research, the optimization of KD/KL will strongly depend on inflection voltage and high and low noise margins (NMs) of butterfly characteristics. The improvement of NMs of butterfly characteristics has been done by increasing the drain current (Ids) of the driver transistor. Also, the optimization in principle will depend on whether NMs are equal and high, and the inflection voltage (Vinf) is near to Vdd/2 values as possible. These principles have been used as limiting factors for optimization. The results show that the optimization strongly depends on the nanowire ratio, and the best ratio was KD/KL 4. The increase in KD/KL leads to a continuous increase in NMH, acceptable NML and low percentage increment of static power consumption (ΔP %) at KD/KL 4. [ABSTRACT FROM AUTHOR]

We propose a previously unexplored way to form Nb nanowires from NbCl 3 molecules inside carbon nanotubes (CNTs). We have studied this reaction by ab initio density functional calculations and found it to be catalytically promoted in presence of graphitic carbon. Our results suggest that chemisorption of NbCl 3 on the CNT is accompanied by a charge transfer of ≈ 0.5 electrons to the nanotube wall, which significantly weakens the Nb–Cl bond. We found that the bcc structure of Nb is not affected by the small diameter of the nanowire inside a CNT. We have also identified strong covalent bonds between the nanowires and the surrounding nanotube that are accompanied by a similar charge transfer of ≲ 0.5 e from surface Nb atoms to the nanotube. The large electronic density of states of bulk Nb at E F is not changed much in the confined geometry, suggesting that ultra-narrow nanowires of Nb may keep their superconducting behavior and form Josephson junctions in the quasi-1D geometry while being protected from the ambient by the enclosing CNT structure. Image 1 [ABSTRACT FROM AUTHOR]

We solve the Landau-Lifshitz-Gilbert equation in the finite-temperature regime, where thermal fluctuations are modeled by a random magnetic field whose variance is proportional to the temperature. By rescaling the temperature proportionally to the computational cell size Δ x (T → T Δ x / a eff , where a eff is the lattice constant) [M. B. Hahn, J. Phys. Comm., 3:075009, 2019], we obtain Curie temperatures T C that are in line with the experimental values for cobalt, iron and nickel. For finite-sized objects such as nanowires (1D) and nanolayers (2D), the Curie temperature varies with the smallest size d of the system. We show that the difference between the computed finite-size T C and the bulk T C follows a power-law of the type: (ξ 0 / d) λ , where ξ 0 is the correlation length at zero temperature, and λ is a critical exponent. We obtain values of ξ 0 in the nanometer range, also in accordance with other simulations and experiments. The computed critical exponent is close to λ = 2 for all considered materials and geometries. This is the expected result for a mean-field approach, but slightly larger than the values observed experimentally. • Simulation of temperature effects using a stochastic Landau-Lifshitz-Gilbert equation. • Accurate determination of the Curie temperature for Cobalt, Nickel, and Iron. • Determination of the scaling law of the Curie temperature with the size of the system, for nanowire and nanolayer geometries. [ABSTRACT FROM AUTHOR]

Penta-twinned and single crystal silver nanowires were bent in-situ for TEM structural analysis using high spatial resolution scanning precession electron diffraction. Machine learning methods were used to determine the structure of the localised bends in the wires. Single crystal nanowires showed both dispersed large radius bend deformation and abrupt, angular bends with narrow deformation zones accommodated by a high angle boundary plane. The penta-twinned wires were found to display simple in-plane bends with narrow deformation zones in all 5 sub-crystals of the wire, with a common boundary plane. A coincident site lattice model has been developed to explain the bending angles seen in individual nanowires and the observed distribution of angles in a population of penta-twinned nanowires. The geometrical constraints of the model explain the difference in this distribution when compared to that from a population of single crystal nanowires. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The properties of polymer based composites are seriously affected by the dispersibility of fillers in the polymer matrix. Chemical modification the surface of fillers is generally employed to achieve excellent dispersibility. However, chemical modification of the additives complicates the fabricating process and increases the cost of the prepared composites. Herein, we report enhancing dielectric and energy storage properties of polyarylene ether nitrile (PEN) by incorporating one-dimensional nanostructured barium titanate nanowires (BT-NWs). Four BT-NWs whose mean aspect ratio is 8.6, 11.6, 16.8 and 30.7, respectively, are prepared via a two-step hydrothermal reaction procedure and characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Afterwards, BT-NW/PEN nanocomposites are prepared by solution casting method. Results demonstrate that BT-NWs are dispersed in the PEN substrate without aggregation and excellent mechanical properties of the composites are obtained. Due to the nanowire nature of the BT-NWs, the dielectric constant of the BT-NW/PEN composites increases obviously with the increasing content and mean aspect ratio of BT-NW. The prepared BT-NW/PEN composites demonstrate an energy storage density up to 1.55 J/cm3, intensifying competitiveness of BT-NW/PEN composites for applications as film capacitors. [ABSTRACT FROM AUTHOR]

This paper reports on the successful fabrication of α‐Si3N4‐nanowire/Y2Si2O7 composite membranes with superhydrophobic properties, aiming to achieve a high performance in membrane distillation. The starting powder mixture of 87 wt% γ‐Y2Si2O7, 5 wt% Si, 3 wt% LiYO2, and 5 wt% ferrocene catalyst was dispersed in a stable suspension, and after being tape‐casted, it was sintered at 1300°C for 4 hours in order to obtain the composite membrane. α‐Si3N4 nanowires with a diameter of about 50 nm were formed, distributed uniformly on the surface and in the pores of the membrane and their presence greatly favored superhydrophobicity. After surface modification with a robust hydrophobic layer of SiNCO nanoparticles, strongly adhered to the surface of the produced membrane, a water contact angle of 153o, was measured. Water desalination experiments, using a sweeping gas membrane distillation (SGMD) device, were conducted. High water flux of 11.91 L/m2/h was achieved for a 4 wt% NaCl feeding solution at 90°C. Stable water flux and rejection rates were recorded in long‐term experiments (>500 hours) using the produced superhydrophobic composite membrane. [ABSTRACT FROM AUTHOR]

• A non-carbon free standing nanowire electrode structure without current collector, additives, and binders is fabricated. • The formation of metal silicide (germanide) at intersections accelerates electron transport inside electrode. • The space between nanowires accommodates the volume contraction of Si (Ge) during alloying and dealloying process. Silicon (Si) and germanium (Ge) can alloy with lithium to achieve high theoretical specific capacities (3579 mAh/g for Li 15 Si 4 and 1384 mAh/g for Li 15 Ge 4), which are several times greater than commercial graphite (372 mAh/g). However, they exhibit significant volume and crystal structural change during cycling processes, leading to structural pulverization and loss of electrical conduction paths between individual active materials and current collector. We report a non-carbon based free standing electrodes fabricated by directly mixing Si and Ge nanowires with Cu nanowires as lithium ion battery anodes. The one dimensional nanostructure of Si (Ge) and Cu provide good charge transport along their length and many contact points were formed between NWs after annealing process. The nanowire composites have several advantages compared to the conventional electrode that slurry materials are coated on a metal foil. For example, the weight is lighter than conventional electrodes because it does not need a current collector and is fabricated without any additives, and binders. Moreover, the space among the nanowires can accommodate the volume contraction of Si (Ge) during alloying and dealloying process and enhance the electrolyte penetration. [ABSTRACT FROM AUTHOR]

Single crystalline bismuth nanowire is recently considered as one of the most attractive low dimensional materials for the exploration of exotic higher-order topological properties. However, its growth mechanism by sputtering, which is regarded as one of the most cost-effective and simplest method, is still unrevealed. In this work, a bismuth nanowire growth model based on surface diffusion driven by chemical potential difference among crystal facets is proposed for sputtering method. The morphology evolution of bismuth nanowires is captured for the first time, and three corresponding growth stages are clearly discriminated. The possible self-catalyzed, stress-driven, and screw dislocation-driven nanowire growth mechanisms are precluded separately based on the theoretical and experimental data. The thoroughly understanding of growth mechanism is fundamental and necessary for fabrication of size-controllable bismuth nanowires and may pave the way for the preparation of other low dimensional materials and the investigation of novel physics. [ABSTRACT FROM AUTHOR]

Herein, porous NiMoO 4 @C nanowire is purposefully synthesized using oleic acid as carbon source, and further evaluated as high performance anode material for Li-ion batteries (LIBs). Compared with the pure NiMoO 4 , porous NiMoO 4 @C nanowire exhibits high reversible charge/discharge specific capacity, excellent cycle stability and preeminent rate capability. A stable reversible lithium storage capacity of 975 mAh g−1 can still be maintained after 100 cycles at 200 mA g−1. When the current density decreases back from 3000 mA g−1 to 100 mA g−1, a high discharge specific capacity of 884 mAh g−1 is recovered. The porous structure and carbon layers can enhance the electronic transmission and structural stability, shorten the path lengths for ion and electron transport, and provide a mechanical buffer space to accommodate the volume expansion/contraction during the repeated Li+ insertion/extraction processes. All the results highlight that the porous NiMoO 4 @C nanowire composite would be a promising candidate for high performance anode material of LIBs owing to its excellent electrochemical properties. [ABSTRACT FROM AUTHOR]

In this study, we have investigated delivery of cisplatin as the anticancer drug molecules in different carbon nanotubes (CNTs) in the gas phase using molecular dynamics simulation. We examined the shape and composition of the releasing agent by using the different nanowires and nanoclusters. We also investigated the doping effect on the drug delivery process using N‐, Si, B‐, and Fe‐doped CNTs. Different thermodynamics, structural, and dynamical properties have been studied by using the pure and different doped CNTs in this study. Our results show that the doping of the CNT has significant effect on the rate of the drug releasing process regardless of the composition of the releasing agent. © 2019 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

• Development of an effective one-pot surfactant-directing aqueous synthesis for ultrathin anisotropic multicomponent noble metal-phosphorus NWs. • Precise controllability in elemental ratios and compositions of ultrathin NMP NWs under the similar synthetic conditions. • Remarkably enhanced electrocatalytic performance in ethanol oxidation reaction, due to synergistically structural and compositional advantages. Noble metal-phosphorus (NMP) alloys have received special attention in the electrocatalysis. Despite a few efforts, the fabrication of anisotropic multicomponent NMPs is largely unsuccessful. Here we develop a facile yet general surfactant-directed aqueous synthesis for one-dimensional (1D) ternary PdCuP alloy nanowires (NWs), and demonstrate their structural and compositional synergy in promoting catalytic performance towards ethanol electrooxidation. Anisotropic PdCuP NWs with an ultrathin diameter of 2.5 nm and ultralong length of hundreds of nanometers are synthesized via in-the-columnar epitaxial growth of crystalline alloys along columnar assemblies of amphiphilic dioctadecyldimethylammonium chloride (DODAC) by NaH 2 PO 2 as the reducing agent and P source simultaneously. This protocol is also synthetically universal, enables the controllability in tuning the P contents and elemental compositions of multicomponent NMP NWs (for example, binary PdP, ternary PdAgP and PdPtP NWs). With synergistically structural and compositional merits, ultrathin PdCuP NWs display dramatically enhanced ethanol electrooxidation performance with a superior mass activity of 6.7 A mgPd−1, which is 9.4 fold higher than commercial Pd nanoparticle catalyst and also surpasses previously reported nanocatalysts. This approach will provide a new access for rational design of anisotropic non-metal-alloyed multicomponent noble metal-based nanocatalysts with desirable functions and synergies for a wide range of (electro)catalytic applications. [ABSTRACT FROM AUTHOR]

Silver nanowires (AgNWs) based conductive electrode have shown potential for use in large area flexible optoelectronic applications. Presently, considerable efforts are being made to lower the surface roughness and enhance the opto-electrical performance of AgNWs based transparent conductive electrode(TCE) for optoelectronic application, which require a smooth surface for high efficiency performance. In this work, we designed a hybrid metal electrode with low surface roughness fabricated by coating an AgNWs onto a metal mesh on Polyethylene terephthalate substrate (AgNW/MM/PET). The AgNW/MM/PET TCE, fabricated by a method of hot pressing after wire wound-rod coating process, exhibits a low surface roughness of 8 nm and 16.33 nm of maximum peak-to-valley value with the low sheet resistance of 0.668 Ω/sq. and a high optical transmittance of 91.25% at λ = 550 nm. In addition, the hot pressed AgNW/MM/PET TCE shows excellent mechanical stability along with long-term reliability in bending tests and strong adhesion in taping test, compared to the annealed AgNW/MM/PET TCE. Therefore, the hot pressed AgNW/MM/PET electrodes with low surface roughness and high opto-electrical performance could be a potential candidate to replace indium doped tin oxide electrodes in flexible electronic application. • Hot pressed Silver nanowire (AgNW) on Metal mesh (MM) electrode was prepared. • Hot pressed AgNW/MM/PET electrode exhibited low surface roughness of 8 nm. • Hot pressed AgNW/MM/PET exhibits 0.668 Ω/sq. with 91.25% of transmittance. • Hot pressed AgNW/MM/PET electrode was reliable in bending and taping test. [ABSTRACT FROM AUTHOR]

The interconnecred PtIr alloy nanowires were uniformly deposited on carbon cloth via One-step wet chemistry method, which diameter is averaged to be 5 nm with a length of 50–200 nm. The carbon cloth supported PtIr nanowire assembly (PtIr NA/CC) shows a larger electrochemical active surface area (ECSA) due to its 3D nanostructure and a high CO-resistance as a result from the synergistic effect of PtIr alloy. The PtIr NA/CC exhibits an extremely high mass activity and a reliable long-term stability toward methanol oxidation reaction (MOR). The superior catalytic performance on MOR can match and even surpass those best Pt-based nanowires reported recently in the literature. • The interconnecred PtIr alloy nanowires were uniformly grown on carbon cloth. • The diameter of PtIr alloy nanowires was 4–6 nm with a length of 50–200 nm. • They show a high electrocatalytic activity toward methanol oxidation reaction. • The mass activity can reaches up to 1.91 A mg−1 with reliable long-term stability. [ABSTRACT FROM AUTHOR]

Silicon nanowires (Si NWs) are the most promising candidates for recording biological signals due to improved interfacing properties with cells and the possibility of high-speed transduction of biochemical signals into detectable electrical responses. The recording of extracellular action potentials (APs) from cardiac cells is important for fundamental studies of AP propagation features reflecting cell activity and the influence of pharmacological substances on the signal. We applied a novel approach of using fabricated Si NW field-effect transistors (FETs) in combination with fluorescent marker techniques to evaluate the functional activity of cardiac cells. Extracellular AP signal recording from HL-1 cardiomyocytes was demonstrated. This method was supplemented by studies of the pharmacological effects of stimulations using noradrenaline (NorA) as a modulator of functional activity on a cellular and subcellular levels, which were also tested using fluorescent marker techniques. The role of calcium alteration and membrane potential were revealed using Fluo-4 AM and tetramethylrhodamine, methyl ester, perchlorate (TMRM) fluorescent dyes. In addition, chemical treatment with sodium dodecyl sulfate (SDS) solutions was tested. The results obtained demonstrate positive prospects for AP monitoring in different treatments for studies related to a wide range of myocardial diseases using lab-on-chip technology. • A novel approach has been demonstrated and successfully verified before as well as after pharmacological treatment. • High-quality Si NW FET biosensors and fluorescence imaging with Calcein AM and DAPI fluorescent markers. • The increased fluorescence response was revealed after adding NorA. • The results obtained represent a new strategy for the investigation of various diseases. • Future applications for cellular characterization and diagnostics. [ABSTRACT FROM AUTHOR]