Smart Electronic Devices Research Articles

Manufacturing of Nanocomposites via Powder Injection Molding: Focusing on Thermal Management Systems—A Review

AbstractThe rapid evolution of electronic and information technology has increased the performance of the electronic processors significantly. Achieving the optimal performance in a smart electronic device poses a serious challenge as the heat generated during operation will reduce the performance of the device which makes thermal management a determinant factor. Powder injection molding (PIM) is an appropriate and relatively new technology used for mass production of small delicate parts with complex shapes and desired properties. One of the latest advances in the PIM process is the production of metal matrix nanocomposites with huge industrial applications, particularly in electronics manufacturing. Manufacturing of efficient complex-shaped nanocomposites, as thermal management components (passive heatsink), could be achieved through the PIM process. On the other hand, what could pose a challenge is the presence of nanoparticles affecting on the different stages of PIM process including feedstock preparation, molding, debinding, and sintering. In this paper, the effect of nanoparticles on different stages of PIM for the production of heatsinks is investigated. Then, the manufacturing of Cu-, Al-, and Mg-based nanocomposites by powder injection molding, as heatsinks, is reviewed followed by investigating the related advantages and limitations.

Biferroic properties in Co-doped 0.2BaZrO3-0.8BaTiO3 materials

Combination in both ferroic properties in current lead-free ferroelectric materials is promising in creating a new type of smart electronic devices. In this report, single perovskite Co-doped 0.2BaZrO3-0.8BaTiO3 materials were synthesized by using the chemical method. The random incorporation of Co cations into the host lattice of 0.2BaZrO3-0.8BaTiO3 compounds resulted in distortion of the lattice parameter and strong reduction the optical band gap energy. Decreasing optical band gap energy was obtained from around 3.17 to 2.52 eV by introducing Co concentration of up to 9 mol.%. The magnetic properties of 0.2BaZrO3-0.8BaTiO3 compounds were showed in complex as dependent on the level of Co dopants. The nonlinear electrical polarization in 0.2BaZrO3-0.8BaTiO3 compounds was obtained and remained after the introduction of Co impurities. The observation in nonlinear in magnetism and electrical polarization were promised to transfer their materials for device applications.

Design of Kinetic-Energy Harvesting Floors

Alternative energy generated from people’s footsteps in a crowded area is sufficient to power smart electronic devices with low consumption. This paper aims to present the development of an energy harvesting floor—called Genpath—using a rotational electromagnetic (EM) technique to generate electricity from human footsteps. The dynamic models of the electro-mechanical systems were developed using MATLAB®/Simulink to predict the energy performances of Genpath and help fine-tune the design parameters. The system in Genpath comprises two main parts: the EM generator and the Power Management and Storage (PMS) circuit. For the EM generator, the conversion mechanism for linear translation to rotation was designed by using the rack-pinion and lead-screw mechanism. Based on the simulation analysis, the averaged energy of the lead-screw model is greater than that of the rack-pinion model. Thus, prototype-II of Genpath with 12-V-DC generator, lead-screw mechanism was recently built. It shows better performance when compared to the previous prototype-I of Genpath with 24-V-DC-generator, rack-pinion mechanism. Both prototypes have an allowable displacement of 15 mm. The Genpath prototype-II produces an average energy of up to 702 mJ (or average power of 520 mW) per footstep. The energy provided by Genpath prototype-II is increased by approximately 184% when compared to that of the prototype-I. The efficiency of the EM-generator system is ~26% based on the 2-W power generation from the heel strike of a human’s walk in one step. Then, the PMS circuit was developed to harvest energy into the batteries and to supply the other part to specific loads. The experiment showed that the designed PMS circuit has the overall efficiency of 74.72%. The benefit of the design system is for a lot of applications, such as a wireless sensor and Internet of Thing applications.

Technology Driven Newer Ingested Foreign Body: A Case Report.

As technology advances there are chances of new hazards to health also increases. In the current era of the digitalized world using a smart electronic device may cause harm to the children. We reported a case of foreign body ingestion which is new in the field of ENT practice. A 1-year-old male child patient presents with an ingested foreign body memory card guard slot cover. To date, this is a newer one in all types of an old foreign body reported in ENT practice.

Design and characterization of a new (1-x)Na1/2Bi1/2TiO3+xBi(Ti1/2Fe1/2)O3 solid solution

A new solid solution, (1-x)Na1/2Bi1/2TiO3+xBi(Ti1/2Fe1/2)O3, was fabricated via the sol-gel method. X-ray diffraction spectroscopy revealed that the structures of Bi(Ti1/2Fe1/2)O3-modified Na1/2Bi1/2TiO3 compounds exhibited the rhombohedral symmetry of Bi1/2Na1/2TiO3. Optical band gap values decreased from 3.06 eV for pure Na1/2Bi1/2TiO3 materials to 2.51 eV for 9 mol.% Bi(Ti1/2Fe1/2)O3-modified Na1/2Bi1/2TiO3 samples. The magnetic properties of Bi1/2Na1/2TiO3 materials were tuned by controlling the amount of Bi(Ti1/2Fe1/2)O3 as solid solution. The weak-ferromagnetism and diamagnetism of pure Na1/2Bi1/2TiO3 materials changed into ferromagnetism and ended with ferromagnetism versus paramagnetism and/or antiferromagnetism-like as the concentration of Bi(Ti1/2Fe1/2)O3 increased to 9 mol.%. We provided that our work will contribute to the integration of ferromagnetism at room temperature in current lead-free ferroelectric compounds for application in smart electronic devices.

Wearable sensing devices for upper limbs: A systematic review.

Wearable sensing devices, which are smart electronic devices that can be worn on the body as implants or accessories, have attracted much research interest in recent years. They are rapidly advancing in terms of technology, functionality, size, and real-time applications along with the fast development of manufacturing technologies and sensor technologies. By covering some of the most important technologies and algorithms of wearable devices, this paper is intended to provide an overview of upper-limb wearable device research and to explore future research trends. The review of the state-of-the-art of upper-limb wearable technologies involving wearable design, sensor technologies, wearable computing algorithms and wearable applications is presented along with a summary of their advantages and disadvantages. Toward the end of this paper, we highlight areas of future research potential. It is our goal that this review will guide future researchers to develop better wearable sensing devices for upper limbs.

A Single‐Material Multi‐Source Energy Harvester, Multifunctional Sensor, and Integrated Harvester–Sensor System—Demonstration of Concept

Single‐source energy harvesters that convert solar, thermal, or kinetic energy into electricity for small‐scale smart electronic devices and wireless sensor networks have been under development for decades. When an individual energy source is insufficient for the required electricity generation, multi‐source energy harvesting is indicated. Current technology usually combines different individual harvesters to achieve the capability of harvesting multiple energy sources simultaneously. However, this increases the overall size of the multi‐source harvester, but in microelectronics miniaturization is a critical consideration. Herein, an advanced approach is demonstrated to solve this issue. A single‐material energy harvesting/sensing device is fabricated using a (K0.5Na0.5)NbO3‐Ba(Ni0.5Nb0.5)O3–Δ (KNBNNO) ceramic as the sole energy‐conversion component. This single‐material component is able simultaneously to harvest or sense solar (visible light), thermal (temperature fluctuation), and kinetic (vibration) energy sources by incorporating its photovoltaic, pyroelectric, and piezoelectric effects, respectively. The interactions between different energy conversion effects, e.g., the influence of dynamic behavior on the photovoltaic effect and alternating current–direct current (AC–DC) signal trade‐offs, are assessed and discussed. This research is expected to stimulate energy‐efficient design of electronic devices by integrating both harvesting and sensing functions in the same material/component.

Visible-light triggered self-breathing-like dual-photoelectrode internal-driven self-powered sensor: Metal–ligand charge transfer (MLCT) induced signal-off strategy for the microcystin-LR assay

Developing new self-powered sensors is highly demanded for smart portable electronic devices. Herein, a novel visible-light-driven self-powdered aptasensor with a metal-ligand charge transfer (MLCT)-induced signal-off strategy was established for microcystin-LR (MC-LR) sensing. The aptasensor was based on a self-breathing-like dual photoelectrode photocatalytic fuel cell (PFC) that was assembled with visible-light responsive ternary NG-TiO2-Ag and NG-BiOBr nanocomposites as photoelectrodes. The device did not require aeration or a membrane in a single-compartment cell. The self-powdered PFC system exhibited a greater power output than previously-reported ones that used only TiO2. The photo-triggered self-bias between the photoelectrodes generated electron transfer and a power output in the external circuit. A self-powered aptasensor for MC-LR was constructed using an MC-LR-binding aptamer as the recognition element. The results showed an unexpected sequential decrease in power output, followed by the capture of MC-LR, which is different from earlier signal-on strategies. The inhibited output of the PFC after MC-LR capture was controlled by an MLCT-induced signal-off mechanism, which was confirmed by the UV–Vis absorption and fluorescence emission spectra. Furthermore, the power output of the self-powdered sensor depended on the MC-LR concentration. When used for ultrasensitive trace MC-LR detection, the self-powdered sensor showed a linear relationship from 1 pM to 316 nM and a detection limit of 0.33 pM. This work provides theoretical guidance for sensing strategies using self-powdered sensors and offers a rational device design for cost-effective electricity generation from renewable resources.

Matching design of high-performance electrode materials with different energy-storage mechanism suitable for flexible hybrid supercapacitors

The realization of advanced hybrid supercapacitors needs the optimal match of different types of high-performance electrode materials. Porous biomass carbon with high specific surface area of 2217.8 m2 g−1 and large specific capacity of 112.5 mAh g−1 (337 F g−1) is prepared from cornstalk. Battery-type Ni3Se2 nanoarray materials with ultra-long nanowire array structure and the specific capacity of 132.4 mAh g−1 are synthesized via a facile solvothermal method. Due to the structure and performance advantages of porous biomass carbon and Ni3Se2 nanoarrays, flexible hybrid supercapacitors are assembled by matching-design of electrode materials with different energy-storage mechanism. This full-cell flexible hybrid device has a wide voltage window of 0–1.6 V, superior energy density of 38.8 Wh kg−1, excellent mechanical flexibility and low-temperature resistance. Therefore, the current work not only shows a feasible designing-method for flexible hybrid supercapacitors, but also provides a promising candidate for small, flexible, and smart electronic device.

Corrigendum to “Synthesis and fabrication of self-sustainable triboelectric energy case for powering smart electronic devices” [Nano Energy, Volume 73, July 2020, 104774

Corrigendum to “Synthesis and fabrication of self-sustainable triboelectric energy case for powering smart electronic devices” [Nano Energy, Volume 73, July 2020, 104774

Conductive Ni3(HITP)2 MOFs thin films for flexible transparent supercapacitors with high rate capability

The flexible transparent supercapacitors have been considered as one of the key energy-storage components to power the smart portable electronic devices. However, it is still a challenge to explore flexible transparent capacitive electrodes with high rate capability. Herein, conductive Ni3(HITP)2 (HITP = 2,3,6,7,10,11-hexaiminotriphenylene) thin films are adopted as capacitive electrodes in flexible transparent supercapacitors. The Ni3(HITP)2 electrode possesses the excellent optoelectronic property with optical transmittance (T) of 78.4% and sheet resistance (Rs) of 51.3 Ω sq–1, remarkable areal capacitance (CA) of 1.63 mF cm−2 and highest scan rate up to 5000 mV s−1. The asymmetric Ni3(HITP)2//PEDOT:PSS supercapacitor (T = 61%) yields a high CA of 1.06 mF cm−2 at 3 μA cm−2, which maintains 77.4% as the current density increases by 50 folds. The remarkable rate capability is ascribed to the collaborative advantages of low diffusion resistance and high ion accessibility, resulting from the intrinsic conductivity, short oriented pores and large specific areas of Ni3(HITP)2 films.

A human-machine interactive hybridized biomechanical nanogenerator as a self-sustainable power source for multifunctional smart electronics applications

Biomechanical energy harvesting has been attracting increased attention for powering electronic devices and reducing battery dependency. Here, we report a human–machine interactive hybridized biomechanical nanogenerator (HMI-HBNG) including an electromagnetic generator (EMG) using a Halbach magnet array and an interdigitated electrode-based triboelectric nanogenerator (TENG). The Halbach magnet array enhances the magnetic flux density, increasing the output power of the EMG eightfold. Introducing a nanowire structure in a polytetrafluoroethylene (PTFE) film and incorporating a novel phase inversion technique for microstructure modifications in the nylon/11 film increase the energy harvesting efficiency of the TENG. The performance of the HMI-HBNG is investigated from different perspectives and shows a maximum output power density of 185 W/m2 across an optimum load resistance of 1.6 kΩ at 5 Hz under 20 m/s2 acceleration. In a human motion experiment, the HMI-HBNG charges a Li-ion battery (18 mAh) from 0 V to 3 V in approximately 10 s and operates multiple electronics devices simultaneously for 3 min. By using a customized power management circuit, the HMI-HBNG can provide a self-sustainable power source for driving multifunctional smart electronic devices, including Bluetooth computer mice, smartwatches, and smartphones. This work represents significant progress toward a self-powered system and practical power source.

Growth and magnetic properties of new lead-free (1 − x)Bi1/2Na1/2TiO3 + xBi(Ti1/2Co1/2)O3 solid solution materials

The new solid solution system of (1 − x)Bi1/2Na1/2TiO3 + xBi(Ti1/2Co1/2)O3 materials was fabricated using the sol–gel method. The structural studies via X-ray diffraction and Raman scattering indicated that Bi(Ti1/2Co1/2)O3 materials were well dissolved into host Bi1/2Na1/2TiO3 materials to follow the rhombohedral structure of host materials. The diffuse cations of Bi(Ti1/2Co1/2)O3 to random incorporation with host lattice to form as solid solution in host Bi1/2Na1/2TiO3 materials resulted in distortion lattice parameter and reduced the optical band-gap values from 3.06 to 2.32 eV for pure and 9 mol% Bi(Ti1/2Co1/2)O3 solute into host Bi1/2Na1/2TiO3 materials. The compensative diamagnetism and weak ferromagnetism of pure Bi1/2Na1/2TiO3 materials were tuned to ferromagnetism at room temperature as increasing the Bi(Ti1/2Co1/2)O3 amounts solute into host Bi1/2Na1/2TiO3 materials. The observation of the room-temperature ferromagnetism in Bi(Ti1/2Co1/2)O3-modified Bi1/2Na1/2TiO3 system was important to integrate the ferromagnetic properties in lead-free ferroelectric materials for further application in smart electronic devices which were required multifunctional materials.

Magnetic Properties of (1 − x)Bi0.5Na0.5TiO3 + xCaCoO3−δ Solid-Solution System

The (1 − x)Bi0.5Na0.5TiO3 + xCaCoO3−δ solid-solution system has been fabricated by a simple sol–gel route. X-ray diffraction analysis and Raman scattering measurements were performed to determine the structure of the solid-solution system. The samples were polycrystalline and had perovskite structure with rhombohedral symmetry. With increasing concentration of CaCoO3−δ solid solution in the host Bi0.5Na0.5TiO3, the optical bandgap reduced from 3.06 eV for pure Bi0.5Na0.5TiO3 to 2.15 eV for 9 mol.% CaCoO3−δ-modified Bi0.5Na0.5TiO3. This process also suppressed the photoluminescence of the host Bi0.5Na0.5TiO3. Weak ferromagnetism as well as diamagnetism were observed for pure Bi0.5Na0.5TiO3, changing to ferromagnetism and finally compensated ferromagnetism versus paramagnetism and/or antiferromagnetic-like behavior as the concentration of CaCoO3−δ was increased. Such introduction of ABO3 impurities containing alkaline-earth and transition metals into the host Bi0.5Na0.5TiO3 could therefore enhance the magnetic properties of this lead-free ferroelectric material to produce multiferroic materials for use in smart electronic devices.

Highly Conductive MXene Film Actuator Based on Moisture Gradients.

MXene (Ti3 C2 Tx ) is a new 2D material with both hydrophilicity and high electrical conductivity, and it has shown promise in smart electronic devices. Reported herein is a homogeneous MXene film actuator with high electrical conductivity triggered by moisture gradients. The actuator is highly sensitive to moisture and undergoes deformation, with the maximum bending angle as high as 155° at a relative humidity difference of 65 %. Several analysis methods show that the humidity drive and large deformation of the MXene film occur in situ by asymmetric expansion of the bilayer structure. The combination of deformation and electrical conductivity makes this film applicable to flexible excavators, electrical switches, and other fields, applications that are difficult to achieve directly by using other 2D materials. More importantly, this work further expands the new application range of MXene materials and provides new opportunities for building the next generation of high-conductivity smart actuators.

Highly Conductive MXene Film Actuator Based on Moisture Gradients

AbstractMXene (Ti3C2Tx) is a new 2D material with both hydrophilicity and high electrical conductivity, and it has shown promise in smart electronic devices. Reported herein is a homogeneous MXene film actuator with high electrical conductivity triggered by moisture gradients. The actuator is highly sensitive to moisture and undergoes deformation, with the maximum bending angle as high as 155° at a relative humidity difference of 65 %. Several analysis methods show that the humidity drive and large deformation of the MXene film occur in situ by asymmetric expansion of the bilayer structure. The combination of deformation and electrical conductivity makes this film applicable to flexible excavators, electrical switches, and other fields, applications that are difficult to achieve directly by using other 2D materials. More importantly, this work further expands the new application range of MXene materials and provides new opportunities for building the next generation of high‐conductivity smart actuators.

Anisotropic Conductive Hydrogels with High Water Content.

High water content is hard to be achieved in conductive hydrogels because a mass of conductive constituent is needed to form an internal conductive pathway. Here, we developed anisotropic electrically conductive hydrogels with high water content based on bacterial cellulose (BC). Polystyrene sulfonate (PSS) was grafted to the acryloyl chloride-modified BC to provide a template for the subsequent synthesis of poly(3,4-ethylenedioxythiophene) (PEDOT). The BC-g-PSS/PEDOT hydrogels obtained were electrically conductive owing to the immobilization of PEDOT on the surface of cellulose nanofibers. The hydrogels exhibited an electrical conductivity of 0.24 S cm-1. Further, they demonstrated suppleness in compression (compiled to external compression stress >2.8 MPa and recoverable), inherent high water content (∼95.0 wt %), and anisotropy (anisotropic index of 4.1 in conductivity) from BC. The incorporation of a thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) hydrogel into the BC-g-PSS/PEDOT hydrogel demonstrated a uniaxial thermoresponsive actuation with resistance change. The expected size and resistance change were only observed in the direction vertical to the cellulose nanofiber layers. These hydrogels could accommodate further developments in novel tissue engineering scaffolds, implantable biosensors, and smart soft electronic devices.

Adaptive Protection Strategy in a Microgrid Under Disparate Operating Modes

—Microgrids usually operate in grid-connected or islanded mode. Due to substantial variation in fault current, same protection coordination scheme cannot be applied in both modes. Moreover, network topology keeps on changing due to momentary events. In this paper, an adaptive protection strategy is proposed to avoid any miscoordination between numerical directional overcurrent relays under a fault instance. Through this scheme, the relay settings can be updated online as per the operating mode and prevailing topology. The proposed tactic employs a central protection center with data storage and programming capability, smart electronic devices and communication channels to acquire and transfer real-time data. The relay coordination problem is formulated as a non-linear optimization function, with coordination time interval constraints. The optimal relay settings under both operating modes are obtained through non-linear programming and hybrid genetic algorithm non-linear programming method. To handle contingencies of communication channel failure, a novel inclusive mode settings are also introduced to protect the system in both modes even with line or DG outages. The proposed adaptive approach is tested on a nine bus radial distribution system with DGs. It has been found that the proposed scheme provides reliable system protection under different operating scenario.

Synthesis and fabrication of self-sustainable triboelectric energy case for powering smart electronic devices

In recent times, Triboelectric Nanogenerators (TENG) have attained the focus of the scientific community due to its potential as a medium to harvest mechanical energy from the ambient environment. Human motion has been attributed as a source of mechanical energy to drive electronic devices and sensors through TENG. Based on the principles of single electrode TENG, we have developed a Triboelectricity based Stepping and Tapping Energy Case (TESTEC) which magnifies the prospect to power touch electronic devices by utilizing finger tapping and stepping motion. This novel case was constructed with two single electrode TENG operating through the triboelectric mechanism between human skin and Polyethylene terephthalate (PET) film on the front part and Nitrile Butadiene Rubber (NBR) and PET film on the back part. This cost effective device was further tested by attaching with a cell phone at variable load frequency, airgap and finger combinations where the output response increased with the increased frequencies (60–240 BPM) and air gap (1 cm–5 cm). Maximum output voltages of 14.8 V and 50.8 V were obtained for the front and back parts, respectively. Besides, maximum output powers were observed to be 3.78 W/m 2 at 0.46 MΩ and 6.21 W/m 2 at 1.02 MΩ, respectively. Also, the device was tested by integrating with conventional electronic components including capacitors, bridge rectifiers and 15 LEDs. Based on the results, a electrical circuit has been proposed to power touch cell phones. The device was further modified using Silver (Ag) nanoparticles in the front part. The modified TESTEC provided higher output response compared to the primary TESTEC. The TESTEC can be a self sustainable way to power touch electronic devices which can reudce the necessity to charge electronics devices in the conventional way. In this work, A cost-effective and self-sustainable energy case containing two single electrodes triboelectric nanogenerators has been designed and fabricated to power smart electronic devices by utilizing the mechanical energy generated while using the device or carrying the device. The device was thoroughly tested with real life parameters such as airgaps, load frequencies and finger combinations. Also, it was tested with bridge rectifiers, resistors, capacitors and LEDs to verify its compatibility with conventional electronic components and ability to power smart electronic devices. • PET and NBR based single electrode Triboelectric Nanogenerators have been developed. • Self-sustainable energy case to power smart electronics through tapping and stepping motion. • The output of the energy case was tested for variable load frequency, airgap and finger combination. • The maximum output voltage was recorded to be ~51 for the back part. • The device was further modified and tested using silver nanoparticles.

UV-light modulated Ti3C2Tx MXene/g-C3N4 heterojunction film for electromagnetic interference shielding

With the mushrooming of smart electronic devices, ultrathin Ti3C2Tx MXene based EMI shielding materials with long term durability have aroused much interest. Herein, 2D Ti3C2Tx/g-C3N4 heterojunction films were firstly assembled using cellulose nanofibrils (CNF) as green binder via a solution-based pressured-filtration process. The heterojunction film with Ti3C2Tx/g-C3N4 mass ratio of 5:1 (28.20 µm in thick) exhibited distinguished performance with EMI shielding effectiveness of 42.99 dB in X-band and high tensile strength of 23.85 MPa. Specially, the generation of photo-electrons from g-C3N4 nanosheets reduced TiO2 into lower valence states under 365 nm UV light-irritation, resulting in lower loss on electrical conductivity as well as EMI shielding performance compared to their unilluminated counterparts. The reduction on TiO2 offered by the g-C3N4 enables the heterojunction film to be considered as a promising alternative EMI shielding material for future potential applications, because it can run long time just need UV light modulation.