Promising Material For Electronic Devices Research Articles

Nitrogen-doped carbon quantum dot-decorated In2O3 synaptic transistors for neuromorphic computing

Nitrogen-doped carbon quantum dots (N-CQDs) are promising materials for electronic devices due to their variable bandgap and structural stability. Here, we integrate N-CQDs into In2O3 synaptic transistors with electrolyte gating, resulting in a hybrid structure. The surface functional groups and defects of N-CQDs empower the charge trapping mechanism, permitting controlled conduction and charge regulation, which are crucial for emulating linear and symmetric artificial synaptic devices. Devices incorporating N-CQDs demonstrate enhanced stability and memory characteristics, low energy consumption, consistent retention, and a significant hysteresis window across multiple voltage cycles. Finally, the study emulates biological synapses and cognitive functions, achieving an energy consumption of 10 fJ per synaptic event and a pattern recognition accuracy of 91.2% on the MNIST dataset in hardware neural networks. This work demonstrates the potential of well-manipulating charge trapping in N-CQDs to develop high-performance, nonvolatile synaptic devices.

Effect of Halogen Substituents on Charge Transport Properties of n-type Organic Semiconductors: A Theoretical Study.

Organic semiconductors (OSCs) have received significant attention as promising materials for electronic devices. In this study, we investigate the impact of halogen groups on the charge transport properties of n-type OSC-6,13 bis((triisopropylsilyl)ethynyl)-5,7,12,14-tetraazapentacene (TIPS-TAP). The computed mobilities for TIPS-TAPs substituted with F and Cl exhibit excellent agreement with the experimental values, while the simulation overestimates the electron mobility for TIPS-TAP. Interestingly, the mobility of TIPS-TAP-4F is significantly lower than that of TIPS-TAP-4Cl/Br, despite their similar packing structures. This discrepancy can be attributed to the strong electron-withdrawing effect of fluoride, which reduces the electron transfer integral and increases the reorganization energy. While molecular packing is widely recognized as a dominant factor in charge transport in OSCs, our study highlights the crucial role of electronic effects in charge transport in OSCs. This study provides new insights into the mechanisms underlying charge transport in OSCs.

Investigating the electrical and optical characteristics of lead-free all-inorganic Cs3Sb2Br9 single crystals

In recent years, halide perovskites have emerged as promising materials for electronic devices. While lead-based perovskites have been extensively studied, exploration of lead-free variants has been limited. Here, we highlight the innovation of observing negative photoconductivity (NPC) induced by light, followed by self-recovery, in lead-free Cs3Sb2Br9 perovskite single crystals. Our study reveals the self-trapping of holes at the Vk center, corresponding to the Br2− dimer, within the midband states of this vacancy-ordered perovskite. This leads to the entrapment of photogenerated charge carriers by charged defect states denoted as Vk, creating an internal electrical field that counteracts the externally imposed field, resulting in NPC. We demonstrate the innovation through the construction of a prototype photodetector with notable sensitivity, featuring high responsivity (6.77 mA/W), detectivity (2.83 × 1012 Jones), and a dark-to-light current ratio of approximately 10. This recognition of retroactive photocurrent in optically active perovskite materials holds promise for advancing highly sensitive detectors.

Diffusion Control on the Van der Waals Surface of Monolayers for Uniform Bi‐Layer MoS2 Growth

Abstract2D MoS2 has gained attention for the post‐silicon material owing to its atomically thin nature and dangling bond‐free surface. The bi‐layer MoS2 is considered a promising material for electronic devices due to its better electrical properties than monolayer MoS2. However, the uniform growth of bi‐layer MoS2 is still challenging. Herein, the uniform growth of bi‐layer MoS2 is demonstrated using gas‐phase alkali metal‐assisted metal–organic chemical vapor deposition (GAA‐MOCVD). Thanks to enhanced metal reactant diffusion length in GAA‐MOCVD, the uniform growth of bi‐layer MoS2 film is achieved even at fast nucleation kinetics for a shorter growth time compared to previously reported MOCVD. The bi‐layer MoS2 field‐effect transistors (FETs) show superior electrical properties such as sheet conductance and electron mobility than monolayer MoS2 FETs. The electron mobility of bi‐layer MoS2 FETs with bismuth contacts reaches a maximum of 92.35 cm2 V−1 s−1. Using the partially grown epitaxial bi‐layer (PGEB) MoS2, it is demonstrated that a photodetector showed a near‐infrared photoresponse with a low dark current that is advantageous for both monolayer and bi‐layer applications. The potential expansion of the growth technique to layer‐by‐layer growth can result in boosted performance across a wide spectrum of electronic and optoelectronic devices employing MoS2.

Investigations on electric properties and domain structures of Nd-doped 0.70Pb(Mg1/3Nb2/3)O3–0.30PbTiO3 relaxor ferroelectric ceramics with high piezoelectric properties

Although rare earth neodymium (Nd) doping is common in Pb(Mg1/3Nb2/3)O3–PbTiO3 (PMN–PT) single crystals, it is rarely reported in PMN–PT ceramics. To explore the effect of Nd doping on PMN–PT ceramics, PMN–30PT:xNd3+ (x = 0%, 1%, 2%, and 3%) relaxor ferroelectric ceramics were fabricated using a solid-state method via two-step sintering. An enhanced piezoelectric charge coefficient (d33) of ~870 pC/N and a high piezoelectric strain coefficient (d33⁎) of ~1025 pm/V were achieved for x = 2%. Through Rayleigh analysis of polarization–electric field (P–E) hysteresis loops under small electric fields, it was found that the dielectric property was mainly influenced by the intrinsic contribution (local lattice distortion). Furthermore, by investigating domain configurations, high piezoelectric properties were found to be associated with the domain size reduction and local structural heterogeneity. The results indicate that the PMN–30PT:xNd3+ ceramics is a promising material for electronic devices, and that rare earth Nd doping is an efficient strategy for improving the electronic performance of Pb-based relaxor ferroelectrics.

Fabricated Chemiresistive Sensor for Detection of Ethanol Using NDICY-ZnO Nanohybrid

The high concentration of ethanol vapors can be a biomarker for fatty liver diseases and severely damage the nervous system. Naphthalene diimide (NDI) has been regarded as n-type semiconductor. NDI possesses high electron affinity, thermal stability and electron mobility, which make NDI as a promising material for electronic devices. Therefore, a dipeptide (C = 6-aminocaproic acid, Y = L-tyrosine) functionalized naphthalene diimide based zinc oxide (NDICY-ZnO) nanohybrid has been synthesized <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">via</i> facile single-pot hydrothermal method. The NDICY-ZnO based sensor exhibits a response of 66.4% with response/recovery time of 450/500 sec, respectively upon the exposure of 500 ppm ethanol at 27 °C. It also shows remarkable selectivity to the ethanol vapors compare to other interfering gases and volatile organic compound for instance methanol, benzene, aniline, NO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> S, CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , acetone and formaldehyde. Moreover, NDICY-ZnO nanohybrid sensor performance is also analyzed under varying relative humidity (RH) conditions which highlights the positive effect on ethanol sensing response. The responses at 46%, 75% and 97% RH are recorded as 66.4%, 75.4% and 83.6%, respectively. In addition, NDICY-ZnO fabricated device shows excellent stability, less air sensitivity and reusability for 90 days. These impressive findings facilitate the low-cost and highly selective detection of ethanol under ambient condition.

Inkjet Printing of Few‐Layer Enriched Black Phosphorus Nanosheets for Electronic Devices

AbstractBlack phosphorus (BP) is considered among the promising material for electronic devices. A wide range of studies involving properties, exfoliation, and applications of thin‐layered BP nanosheets (NSs) has been put forward. Along with understanding properties of thin‐layered BP NSs, efforts to enlighten the intrinsic characteristics of the BP film should be also accompanied to extend applications of the material. In this study, a facile and efficient inkjet printing approach is introduced to fabricate patterned BP films. This approach successfully addresses the complexity of the ink formulation and thus enables to pattern the high‐quality BP film at as high a resolution as tens of micrometers. The printed BP pattern provides its intrinsic characteristics including electronic properties, conducting mechanism, and stability, which are essential to advancing the printed BP electronic device. By integrating the printed BP pattern into a diode device, its potential for electronic devices is demonstrated. This inkjet printing technique will facilitate the development of printing patterns of 2D materials in a facile and cost‐effective manner and further boost the research on advanced electronic devices.

High-Speed Fabrication of Clear Transparent Cellulose Nanopaper by Applying Humidity-Controlled Multi-Stage Drying Method.

As a renewable nanomaterial, transparent nanopaper is one of the promising materials for electronic devices. Although conventional evaporation drying method endows nanopaper with superior optical properties, the long fabrication time limits its widely use. In this work, we propose a multi-stage drying method to achieve high-speed fabrication of clear transparent nanopaper. Drying experiments reveal that nanopaper’s drying process can be separated into two periods. For the conventional single-stage evaporation drying, the drying condition is kept the same. In our newly proposed multi-stage drying, the relative humidity (RH), which is the key parameter for both drying time and haze, is set differently during these two periods. Applying this method in a humidity-controllable environmental chamber, the drying time can be shortened by 35% (from 11.7 h to 7.6 h) while maintaining the same haze level as that from single-stage drying. For a conventional humidity-uncontrollable oven, a special air flow system is added. The air flow system enables decrease of RH by removing water vapor at the water/air interface during the earlier period, thus fabricating clear transparent nanopaper in a relatively short time. Therefore, this humidity-controlled multi-stage drying method will help reduce the manufacturing time and encourage the widespread use of future nanopaper-based flexible electronics.

Unraveling the stacking effect and stability in nanocrystalline antimony through DFT

Two-dimensional nanocrystals with semiconducting electronic properties are emerging as promising materials for electronic devices. Here, we present the density functional theory calculations of structural stability, Raman spectra and electronic properties of monolayer, bilayer (AA and AB stacking) and trilayer (AAA and ABC stacking) antimony (Sb). The cohesive energy and phonon band dispersion results revealed that free-standing Sb systems are stable materials. Calculated Raman spectra showed distinct active modes, thus facilitating the characterisation of multilayered structures in different stacking arrangements. It was found that high-frequency in-plane (Eg) and out-of-plane (A1g) modes can shift as much as 16 cm−1 and 28 cm−1 as the layer number increases from monolayer to trilayer. Band structure calculations showed that monolayer and bilayer (AA stacked) Sb are semiconductors with band gap values 1.26 eV and 0.55 eV, respectively, whereas bilayer (AB) and trilayer Sb displayed metallic character. Spin-orbit coupling interaction was also incorporated in band structure calculations and was found to reduce the band gap of monolayer Sb to 1.0 eV while it does not effect on the band gap values of other systems. Moreover, it was seen that nanocrystalline Sb exhibit isotropic mechanical properties. The carrier mobility calculations showed that electron/hole mobility increases by 5/32 times from monolayer to trilayer, respectively.

Al2O3, Al doped ZnO and SnO2 encapsulation of randomly oriented ZnO nanowire networks for high performance and stable electrical devices

Two-dimensional randomly oriented nanowire (NW) networks, also called nanonets (NNs), have remarkable advantages including low-cost integration, good reproducibility and high sensitivity, which make them a promising material for electronic devices. With this work, we focus on the study of ZnO NNs as channel materials in field effect transistors (FETs). In our process, ZnO NWs were assembled in NNs by the liquid filtration method and were integrated in transistors, with the bottom-gate configuration, using simple technological steps. Non-encapsulated devices exhibited state of the art performances but their stability toward air exposure was poor. Using a proper encapsulation of the nanonets, with cheap, abundant and non-toxic oxides, we demonstrate our ability not only to stabilize their electrical properties, but also to enhance performance to values never reach before for ZnO NW-based transistors. Our best FETs exhibit a low Off-current while maintaining a very good On-current, which results in a Ion/Ioff ratio exceeding 106 for a drain voltage of 5 V. The behavior of these ZnO NN-based FETs was studied for three different encapsulation materials, alumina (Al2O3), tin oxide (SnO2) and Al-doped ZnO (AZO). These results prove that ZnO NNs are highly promising materials for an easy and low-cost integration into FETs.

First-principles prediction of two-dimensional metal bis(dithiolene) complexes as promising gas sensors.

The recently synthesized two-dimensional metal bis(dithiolene) complex (MDT), a kind of metal-organic framework with a kagome lattice structure, has been found to be a promising material for electronic devices. Here we report the surface adsorption effects of gas molecules on the electronic properties and transport behaviors of two-dimensional MDT (M = Fe, Co, Ni, Pd, and Pt) films. The first-principles results reveal that the MDT nanosheets are selectively sensitive to different adsorbed molecules, such as CO, NO, and O2 molecules. All the studied gas molecules can be chemically adsorbed on the ferromagnetic FeDT and CoDT nanosheets, whereas the non-magnetic PdDT and PtDT films are only sensitive to NO molecules, showing quite weak interaction with CO and O2. The physisorption of CO on PdDT and PtDT originates from the mismatch of energy levels between the metal dz2 orbitals and the CO σ orbitals. In contrast, the Pd and Pt dxz and dyz orbitals can well align with the NO π* orbitals, causing strong chemisorption. More importantly, the adsorption of NO on PdDT and PtDT not only induces a magnetism of 1.0 μB for the two films but also greatly enhances the conductivity. In the case of PtDT, we observe a transition from the semiconducting to the metallic phase on NO adsorption. This significant change in the electronic structure can be understood from the adsorption-induced interfacial charge transfer and the strong orbital hybridization between the metal d states and the NO π* states. Our results suggest the potential application of the PdDT and PtDT nanosheets in gas sensing and spintronics.

Impedance study of synthesized Cobalt Aluminum Oxide/ Polypyrrole Nano-composites

Conducting polymer polypyrrole is promising material for electronic devices and sensor applications. To enhance its properties ternary compound Cobalt Aluminum Oxide (CAO) Nano powder in different weight percent were added. In presence of oxidizing agent ammonium persulphate CAO/polypyrrole Nano-composites were synthesized by in-situ chemical polymerization method. Synthesized Nano-composites were characterized by FTIR. The FTIR spectra shows the presence of all characteristics absorption peaks of polypyrrole that match well with the ones available in the literatureconfirming the formation of Polypyrrole.Impedance study was carried out for all Nano-composites by precision impedance analyzer in the frequency range 100 Hz to 5 MHz and at different temperatures. Impedance was almost constant over all frequencies for all composites whichreveal resistive part dominates in the impedance and composites shows less impedance as compared to pure polypyrrole.

Preparation and characterisation of fine-grained barium lead titanate ceramics by spark plasma sintering technique

Barium lead titanate ferroelectric ceramic is a promising material for electronic devices at high frequency and high temperatures. These fine-grained ceramics were obtained at a low sintering temperature of 900°C within a short sintering time by means of a new sintering method – spark plasma sintering (SPS). The ceramics are highly densified to >99% of the theoretical X-ray density with homogeneous microstructures, signifying that the SPS process is effective for the densifying of compacts and the inhibition of exaggerated grain growth. Temperature dependence of dielectric constant of SPS pellets shows three times higher than the conventional sintering (CS) Ba0.8Pb0.2TiO3 (BPT) pellet. The variations in properties between SPS and CS materials are mainly because of the differences of the resultant microstructures, especially grain size, of the ceramics.

Characteristics of Silicon Nanoparticles Depending on H2 Gas Flow During Nanoparticle Synthesis via CO2 Laser Pyrolysis

Silicon nanoparticle is a promising material for electronic devices, photovoltaics, and biological applications. Here, we synthesize silicon nanoparticles via <TEX>$CO_2$</TEX> laser pyrolysis and study the hydrogen flow effects on the characteristics of silicon nanoparticles using high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and UV-Vis-NIR spectrophotometry. In <TEX>$CO_2$</TEX> laser pyrolysis, used to synthesize the silicon nanoparticles, the wavelength of the <TEX>$CO_2$</TEX> laser matches the absorption cross section of silane. Silane absorbs the <TEX>$CO_2$</TEX> laser energy at a wavelength of <TEX>$10.6{\mu}m$</TEX>. Therefore, the laser excites silane, dissociating it to Si radical. Finally, nucleation and growth of the Si radicals generates various silicon nanoparticle. In addition, researchers can introduce hydrogen gas into silane to control the characteristics of silicon nanoparticles. Changing the hydrogen flow rate affects the nanoparticle size and crystallinity of silicon nanoparticles. Specifically, a high hydrogen flow rate produces small silicon nanoparticles and induces low crystallinity. We attribute these characteristics to the low density of the Si precursor, high hydrogen passivation probability on the surface of the silicon nanoparticles, and low reaction temperature during the synthesis.

A Review on Ba&lt;sub&gt;x&lt;/sub&gt;Sr&lt;sub&gt;1-x&lt;/sub&gt;Fe&lt;sub&gt;12&lt;/sub&gt;O&lt;sub&gt;19&lt;/sub&gt; Hexagonal Ferrites for use in Electronic Devices

The Ferrite term is used to refer to all magnetic oxides containing iron as major metallic component which has great to technological applications because of their ferromagnetic and insulating properties at room temperature. Among such ferrites, the hexagonal ones (hexaferrites) have long been used for permanent magnets and are of interest for microwave applications. The hexaferrite M-type has a structure built up from the S blocks interposed by the R block and are symbolically described as RSR*S*. In the last decades there has been great interest in the hexaferrites M-Type for applications as electronic components for mobile and wireless communications at microwave/GHz frequencies, electromagnetic wave absorbers for electromagnetic compatibility (EMC), radar absorting material (RAM) and stealth technologies and as composite materials. This review aimed study the structure, magnetic and dielectric properties of the hexaferrite BaxSr1-xFe12O19, which is a promising material for electronic devices and for small dielectric resonator antennas (MRA).The outline of this Review Paper is as follows:

Widely Tunable Carrier Mobility of Boron Nitride‐Embedded Graphene

The carrier transport in boron nitride-embedded graphene (BNG) is studied using density functional theory coupled with the Boltzmann transport equation. Under a phonon scattering mechanism, the intrinsic carrier mobility of BNG at room temperature is tunable from 1.7 × 10(3) to 1.1 × 10(5) cm(2) V(-1) s(-1) when the bandgap is between 0.38 and 1.39 eV. Some specific BNG materials even show ultrahigh mobility up to 6.6 × 10(6) cm(2) V(-1) s(-1) , and the transport polarity (whether it is electron or hole transport) can be tailored by the application of a uniaxial strain. The wide mobility variation of BNG is attributed to the dependence of the effective mass and the deformation potential constant on the carbon concentration and width. The results indicate that BNG can have both a large on-off ratio and high carrier mobility and is thus a promising material for electronic devices.

Fast bolometric sensor built-in into polycrystalline CVD diamond

Diamond, with its unique combination of physical properties, is a promising material for electronic devices operating under extreme conditions. Due to its exceptionally high thermal conductivity, diamond-based bolometers should possess very short response time. A fast bolometric sensor was formed within a polycrystalline diamond plate by ion implantation and subsequent annealing. The response kinetics of the structure was studied under a nitrogen laser pulsed illumination. The response time at room temperature was less than 20 ns. The spatial-temporal distribution of responses allowed us to distinguish between thermal responses and those of different nature (e.g. photoconductivity). This study was supported by the Russian Foundation for Basic Research, project nos. 05-02-17545 and 07-02-00575.

Chiral electrodes of magneto- electropolymerized polyaniline films

Introduction. Magnetic fields induce chiral structures through the Lorentz force acting on currents in electrolytic solutions. Two-dimensional spiral structures were found in the electrodeposition of metals [1, 2] and conducting polymers [3], and three-dimensional helical structures in silicate membrane growth [4], though both structures were on the millimeter scale. If chiral structures on the molecular scale are induced on the surface of the films formed under magnetic fields, such film surfaces would serve as enantioselective catalysts. Enantioselective recognition of chiral molecules is one of the most important processes in biochemistry; in most cases, it is realized by enzymes. Chiral surfaces of heterogeneous catalysts have the enantioselective properties, and thus considerable effort has been devoted to preparing chiral surfaces by adsorbing chiral molecules [5, 6] or slicing single crystals [7]. Chirality was also introduced into conducting polymers by doping chiral molecules [8, 9, 10], and chiral polyaniline films exhibited enantioselective recognition for several amino acids [9]. We attempted to prepare polyaniline films with a chiral surface by magnetoelectropolymerization (MEP), which is electropolymerization under magnetic fields [11]. Polyaniline is one of the most promising materials for electronic devices, and its films are easily prepared by the oxidative electropolymerization of aniline in acidic aqueous solutions. Aniline monomers are stoichiometrically oxidized in front of the polymer chain, and then electrons are transported from the front to the substrate electrode within the chain. Under magnetic fields, the Lorentz force is expected to act on currents within the polymer chain and induce helical growth. Thus, it is interesting to examine whether the MEP films exhibit chiral electrode properties. Here, we show the voltammetric responses of the MEP polyaniline films to vitamin C (L-ascorbic acid) and its enantiomer, erythorbic acid (D-ascorbic acid).

Time-of-flight measurements in thin films of regioregular poly(3-hexyl thiophene)

We have studied the transport of holes in thin films of regioregular poly(3-hexyl thiophene) (RRPHT). In comparison to regiorandom poly(3-hexyl thiophene) (PHT), RRPHT is a promising material for electronic devices, due to the high field effect mobility observed. We have studied the photogenerated charge carrier transport by using the integral time-of-flight (TOF) method. We have also studied the transport properties of the equilibrium charge carriers by a newly developed method of equilibrium charge carrier extraction in the case of a linearly increasing voltage. From TOF measurements in the subnanosecond time scale, it was experimentally obtained that the drift distance of holes is smaller than the inter-electrode distance in both PHT and RRPHT films and the mobility is higher than 10−2 cm2/Vs. In the millisecond time scale we obtained additional low mobility of equilibrium holes in RRPHT.

Chemical Bonding Properties of Cubic III-Nitride Semiconductors

We report on the chemical trends of the physical quantities of cubic III nitrides obtained from first-principles calculations on the basis of the density functional theory within the local density approximation. The results are compared to experimental results of the element semiconductors including diamond, and of III-V and II-VI compound semiconductors. It has been found that (a) BN has strong covalent character comparable to diamond, (b) the chemical bonding properties of AlN and GaN are located in the intermediate between that of other III-V and II-VI materials, and (c) the bond angle of InN is easy to bend more than the other typical III-V, II-VI, and I-VII materials. The group III nitrides have been utilized to fabricate optical devices such as light emitting diodes from red to ultraviolet emission and purplish-blue laser diodes.They are also promising materials for electronic devices in hard environment due to their high chemical stability and extreme hardness.So far a lot of researches have been made on their structural, elastic, piezoelectric, and dielectric properties.However systematic investigation of the chemical bonding properties has not yet been done sufficiently.We report on the chemical trends of cubic III nitrides obtained from first-principles calculations. §2. Computational method