Small Electronic Devices Research Articles

Multi-functional piezoelectric nanogenerator based on relaxor ferroelectric materials (BSTO) and conductive fillers (MWCNTs) for self-powered memristor and optoelectronic devices

Nowadays self-charging memristors and photodetectors open the path for future research into energy-autonomous electronics which hold the promise of enabling exceptionally efficient applications in memory storage, small portable electronics, neuromorphic computing, and optoelectronics devices. Hence, in the recent era, much research work has been focused on the development of nanogenerators for technological applications. In this regard, the main aim of the present study is to develop a multi-functional piezoelectric nanogenerator based on relaxor ferroelectric materials having three-phase MWCNTs/BSTO/PVDF nanocomposites. BSTO and CNT fillers promote >80 % electroactive phase nucleation in PVDF, making it appropriate for piezoelectric energy harvesting devices. Incorporating conductive fillers (CNTs) and dielectric fillers (BSTO) into the PVDF matrix enhances the piezoelectric nanogenerator's dielectric, ferroelectric, and output performance. PENG based on an optimized BSTO-CNTs-PVDF composite (with 20 % BSTO and 0.20 % CNTs loading) produced an output power of 31.5 µW with a high open-circuit voltage of 42 V and a short-circuit current of 9 µA, it demonstrates enough capability to power up small portable electronic devices. This work can also be used for a realistic technique for generating self-powered memristors and photodetectors for extremely efficient memristive neural networks and optoelectronics devices. Demonstration of power generation of the prepared device by different activities is demonstrated.

Enhancing Digital Forensic Investigation: A Focus on Compact Electronic Devices and Social Media Metadata

The rise of portable electronic devices and social media has led to new criminal activities, necessitating advancements in digital forensics. This paper introduces Small-Scale Digital Device Forensics (SSDDF), focusing on the forensic examination of miniature digital devices often used in crimes. SSDDF addresses the challenges posed by these devices, particularly in extracting and analyzing data from them. A key aspect of this research is exploring ontology in social media forensics, particularly within the Android operating system. This involves extracting digital evidence like user accounts, messages, and images from social media platforms. While the paper primarily focuses on social media data, it acknowledges the importance of the devices used in crimes. The integration of SSDDF and the analysis of Android system structures are highlighted as key advancements in digital forensic methodologies. These enhancements are expected to improve the process of collecting and analyzing digital evidence from both compact electronic devices and social media platforms. The study offers significant contributions to the field of digital forensics. It provides new strategies for more efficient and effective forensic investigations, especially in the context of extracting and analyzing digital evidence from small electronic devices and social media, thus paving the way for more robust digital evidence handling in future forensic inquiries.

Optical Vivaldi Antenna Array for Solar Energy Harvesting

In this paper, we try to find the best solution for our energy harvesting application by designing an efficient optical antenna which receives the solar radiation and converts it from AC to DC by integrating a rectifier. This work consists of designing a Vivaldi optical antenna with a maximum electric field captured in its gap. We also examine the use the optical array(double, four and eight) in order to increase the captured electric field concentrated in the common gap, compared to the single structure . Feeding lines are used to ride the captured electric field from the gap of each single antenna to a common gap. These innovative systems are small electronic devices often consisting of a low-power computer, wireless sensors, an antenna and capable of communicate with their environment. These devices also have an on-board energy source in the form of cells or batteries that require maintenance operations. periodic replacement or recharging, which can hinder the mobility and deployment of these communicating systems for the greatest number. This is the reason why we Today, we also note the very strong interest in improving energy autonomy and even the complete independence of these systems with respect to on-board sources.

The Influence of Gadget Use on The Development of Social Interaction in Children Aged 5–6 Years

Various studies and child development experts highlight the risks of using gadgets in early childhood. A gadget is a small electronic device with various special functions that could potentially influence children’s developments. The research method used was quantitative, with a type of correlation research aimed to determine the relationship between variables of gadget use and social interaction development. The data collection technique employed a SAS (Smartphone Addiction Scale) questionnaire sheet to measure the use of gadgets and utilized Ages and Stages Questionnaires: Social Emotional (ASQ: SE) second edition to measure social interaction. The samples involved were children aged 5–6 years, totaling 39 children, 18 boys and 21 girls. The sampling technique used was purposive sampling, which used appropriate categories or criteria to be studied in selecting the sample, namely children aged 5 -6 years. This research revealed that using gadgets influenced the development of social interactions in early childhood by the sig. value of -0.500 indicating the correlation. Children use gadgets because they are more interesting, responsive, and full of challenges than playing with friends in the surrounding environment. Based on the results of this research, the implication is providing parenting to people regarding the impact of gadget use on social interactions.

Lignocellulosic Biomass for the Fabrication of Triboelectric Nano-Generators (TENGs)—A Review

Growth in population and increased environmental awareness demand the emergence of new energy sources with low environmental impact. Lignocellulosic biomass is mainly composed of cellulose, lignin, and hemicellulose. These materials have been used in the energy industry for the production of biofuels as an eco-friendly alternative to fossil fuels. However, their use in the fabrication of small electronic devices is still under development. Lignocellulose-based triboelectric nanogenerators (LC-TENGs) have emerged as an eco-friendly alternative to conventional batteries, which are mainly composed of harmful and non-degradable materials. These LC-TENGs use lignocellulose-based components, which serve as electrodes or triboelectric active materials. These materials can be derived from bulk materials such as wood, seeds, or leaves, or they can be derived from waste materials from the timber industry, agriculture, or recycled urban materials. LC-TENG devices represent an eco-friendly, low-cost, and effective mechanism for harvesting environmental mechanical energy to generate electricity, enabling the development of self-powered devices and sensors. In this study, a comprehensive review of lignocellulosic-based materials was conducted to highlight their use as both electrodes and triboelectric active surfaces in the development of novel eco-friendly triboelectric nano-generators (LC-TENGs). The composition of lignocellulose and the classification and applications of LC-TENGs are discussed.

A hybrid nanogenerator based on wind energy harvesting for powering self-driven sensing systems

The increase in energy demand makes it urgent to explore green energy sources. And wind energy is one of the most promising renewable energy sources. In this paper, a rotating hybrid nanogenerator with a combination of a direct-current triboelectric nanogenerator (DC-TENG) and an electromagnetic generator (EMG) is designed; the design concept is to harvest wind energy. First, an optimized ternary DC-TENG is designed based on the ternary dielectric triboelectrification effect. A soft contact structure is designed, which can effectively increase the frictional area as well as reduce the frictional resistance. Then, by introducing the EMG unit, the output power of the device and the speed of charging the capacitor are increased. The high output voltage of the DC-TENG and the high output current of the EMG complement each other to produce excellent power output. At 180 rpm/min, the output power of DC-TENG and EMG can reach 1.78 mW and 215 mW, respectively. With a simple power management circuit design, the device is successfully implemented to power small electronic devices. By charging a suitable capacitor, the device can be used as a power supply to power the sensor. Together with the sensor and power management circuit, it forms a self-powered sensing system that can drive the sensor for continuous operation. This work provides a simple, convenient, and reliable design that offers new insights into energy harvesting in nature.

Portable IoT-Based Disinfection Box

The COVID-19 pandemic is an ongoing global health event that began in 2019. It is caused by a novel strain of coronavirus known as SARS-CoV-2. Bacteria and viruses can cause illness in human. Therefore, a Portable IoT-based Disinfection Box is developed in this work to disinfect small electronic devices such as smartphone, smartwatch or even a 13-inch tablet, that may come into contact with bacteria and viruses. There are three special features of this Disinfection Box which are the timer itself, Web Interface Monitoring, portable and spacious with dimensions of 29 × 18 × 14 cm3. The ESP32 Wi-Fi module with NodeMCU-32S Base module as a microcontroller is used in this work and it controls the 2-channel Relay in order to turn ON and OFF the UV-C LED light strip. Besides that, it is also connected to the LCD display with I2C module to display the real-time of disinfection process. The Dashboard of Arduino IoT Cloud allows the user to control and monitor the operation of disinfection process. When a small electronic device is placed inside the Disinfection Box, UV-C LED light strip is turned on to begin the disinfection process. The effectiveness of the UV-C LED light strip is investigated by using the Petri dish with agar. It is shown from the experimental procedures that 10-minute disinfection time provided by the Disinfection Box is sufficient to disinfect small electronic devices such as smartphone and smartwatch. This is based on the great reduction of bacteria colonies on the agar in Petri dish after being kept in a dark place with room temperature for 4 days.

Asymmetric GO-PPy based energy generator via synergistic flowing potential and ionovoltaic effect

Harvesting energy from ambient water, a renewable technology of generating electrical energy, promises to relieve the worldwide energy shortage. However, most of the electricity from ambient water is flowing potential, which has a short duration and is greatly affected by external conditions. Herein, a graphene oxide-polypyrrole-nonwoven fabric (GO-PPy-NWF) with asymmetric structure based water-induced energy generator is developed to harvest electricity via synergistic flowing potential and ionovoltaic effect. Electric power of ∼0.86 V and ∼40 μA can be harvested for ∼40 min with 0.1 mL brine or seawater infiltrating into the generator. Moreover, under one sun, the GO-PPy-NWF achieves electric power up to ∼0.93 V due to rapid evaporation. The GO-PPy-NWF harvests electricity by water to light up light emitting diodes (LEDs) and small electronic devices, showing good practicability prospects with flexibility, low cost and sustainability.

A hybrid piezoelectric-electromagnetic energy harvester used for harvesting and detecting on the road

At present, some piezoelectric energy harvesters (PEH) have been widely used in various small wireless electronic devices and micro intelligent sensing devices for self-power supply, but PEH still needs to be further improved in the effective acquisition of road vibration energy at low frequency (<10 Hz), especially at ultra-low frequency (<5 Hz) and broadening the capture energy band. Based on this, this paper proposes a hybrid piezo-electromagnetic road vibration energy harvesting device -TPEH (Triple piezoelectric energy harvester) suitable for road deceleration belts. Spring is introduced as the key to improve the efficiency of energy harvesting. Firstly, the vibration environment of the deceleration belts is surveyed, and then the influence of different K, frequencies, vehicle types and impedance on the energy capture effect is observed in the experiment. The experimental results show that: first of all, K = 20 N/kg main spring has the best resilience; Secondly, with the increase of excitation frequency from 0 Hz to 10 Hz, the maximum peak voltage of TPEH increases from 5.7V to 31.2V, and reaches the full bandwidth in the low frequency range of 0–10 Hz, especially the frequency band widening in the range of 0–1 Hz has ma de a breakthrough. Then, the total output power of TPEH reaches a maximum of 10.29 mW under the optimal load condition of 10 kΩ. Finally, TPEH is applied to the speed strip of a local road section. Through reasonable distribution of vibration signals, TPEH could accurately wireless communication module.

Social Media Metadata Forensic Ontology Model

The escalating use of compact electronic gadgets like smartphones and smartwatches, along with social media platforms, has led to a new dimension of criminal activities. Advancements in digital forensics, which investigates digital evidence, have become noteworthy. Researchers David Christopher Harrill and Richard P. Mislan devised Small-Scale Digital Device Forensics (SSDDF) for examining miniature digital devices used in criminal undertakings. Edlira Kalemi and Sule Yildirim-Yayilgan demonstrated the application of ontology in social media forensics, deciphering Android system frameworks related to social media data extraction. However, their investigations mainly focused on social media, overlooking the role of gadgets used by criminals and victims. Extracting digital data from these devices remains pivotal for securing relevant evidence from social media. Notwithstanding, incorporating SSDDF and understanding Android system structures have significantly contributed to digital forensic methodologies. These enhancements can bolster the investigation process, capturing and analyzing critical digital evidence from compact electronic appliances and social media platforms. The advent of SSDDF and elucidating Android system structures have offered invaluable inputs to digital forensics, enhancing efficacy in amassing significant evidence from small electronic devices and social media platforms.

Sandwich-type double-layer piezoelectric nanogenerators based on one- and two-dimensional ZnO nanostructures with improved output performance

Piezoelectric nanogenerators (PENGs) have attracted great interest owing to their broad range application in environmental mechanical energy harvesting to power small electronic devices. In this study, novel flexible and high-performance double-layer sandwich-type PENGs based on one-dimensional (1-D) and two-dimensional (2-D) zinc oxide (ZnO) nanostructures and Ni foam as the middle layer have been developed. The morphology and structure of 1- and 2-D ZnO nanostructures have been studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD). To investigate the effect of structural design on the piezoelectric performance, single-layer PENGs were also fabricated. The piezoelectric output of all prepared PENGs were evaluated under different human impacts at various forces and frequencies. The double-layer designed PENGs showed a two times larger voltage output compared to the single-layer PENGs, and the use of Ni foam as middle-layer and of 2-D ZnO nanosheets (compared to 1-D nanorods) was also found to increase the performance of the designed PENGs. The working mechanism of the prepared PENGs is also discussed. The design of nanogenerators as double-layer sandwich structures instead of two integrated single-layer devices reduces the overall preparation time and processing steps and enhances their output performance, thus opening the gate for widening their practical applications.

Design and Development of RF Energy Harvesting Module for Low Power Device using Propulsion Concepts in Renewable Energy

Energy harvesting is the need of the hour to operate small, portable and low power electronic devices for self-reliance. We focus our research on radio frequency energy harvesting. We have designed micro strip patch antenna to operate at 2.4GHz. We have analysed the capture of ambient radio frequency energy at various physical locations. We have successfully demonstrated the RF energy harvesting technique proposed for operating devices like LED, scientific calculator and battery charging. In this paper we have verified the RF energy harvesting technique through Hardware implementation.

Non-thermal plasma disinfecting procedure is harmless to delicate items of everyday use

Non-thermal plasma (NTP) is a well-known decontamination tool applicable for a wide range of microorganisms and viruses. Since the recent COVID-19 pandemic highlighted the need to decontaminate all daily used items, it is highly desirable to address the applicability of NTP, including its possible harmful effects. To the best of our knowledge, a comprehensive characterization of NTP effects on sensitive materials is still lacking. We investigated the potential damage to common materials of daily use inflicted by air atmospheric NTP generated in Plasmatico v1.0. The materials tested were paper, various metals, and passive and active electronic components modelling sensitive parts of commonly used small electronic devices. The NTP-exposed paper remained fully usable with only slight changes in its properties, such as whitening, pH change, and degree of polymerization. NTP caused mild oxidation of copper, tinned copper, brass, and a very mild oxidation of stainless steel. However, these changes do not affect the normal functionality of these materials. No significant changes were observed for passive electronic components; active components displayed a very slight shift of the measured values observed for the humidity sensor. In conclusion, NTP can be considered a gentle tool suitable for decontamination of various sensitive materials.

Tensegrity triboelectric nanogenerator for broadband blue energy harvesting in all-sea areas

The integration of high-density friction layer units is a promising approach for achieving high output in triboelectric nanogenerators (TENGs). Yet, the synchronization and sufficient contact separation of these high-density layer units are inherently challenging due to the cumulative impact of gravity. Herein, a tensegrity structure was applied and effectively organized the high-density stacked TENG units into an ordered whole, thereby proposing the T-TENG. Along with achieving orderly contact and separation of high-density friction layers, the T-TENG effectively reduced the device's height (up to 52%) and improved the friction layer surface area density (up to 1.07 cm−1). Significantly, the built-in prestress modulation not only enhances the device's load-bearing capacity but also enables ease in changing the T-TENG's response frequency by adjusting the prestress value. This is especially suitable for efficiently capturing omnidirectional wave energy in all-sea areas with frequency variations. The working mechanism and output influencing parameters of T-TENG were systematically expounded, and it demonstrated a maximum output voltage of up to 1020 V and output charge per unit time of 0.816 mC/min, sufficient to light up to 1512 LEDs directly. Moreover, customization of low-loss gas discharge tubes to amplify outputs allows T-TENG to harvest wave energy for power supply to small electronic devices such as water quality testing pens and Bluetooth modules when placed over water bodies. This work provides a foundational model to develop high-density friction layers and high-output TENGs.

Molecular Catalysts for OER/ORR in Zn–Air Batteries

Zn–air batteries are becoming the promising power source for small electronic devices and electric vehicles. They provide a relatively high specific energy density at relatively low cost. This review presents exciting advances and challenges related to the development of molecular catalysts for cathode reactions in Zn–air batteries. Bifunctional electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) play the main role in improving performance of reversible fuel cell and metal–air batteries. The catalyst development strategies are reviewed, along with strategies to enhance catalyst performance by application of magnetic field. Proper design of bifunctional molecular ORR/OER catalysts allows the prolongment of the battery reversibility to a few thousand cycles and reach of energy efficiencies of over 70%.

Design of a multicylinder crank-slider wind energy harvester utlizing Faraday's law of electromagntic induciton

Advancement in smart electronic devices such as smartphones, smart watches, tablets have impacted the requirement of supplying continuous energy for powering and functioning of these devices. There have been several research studies performed on harvesting energy from mechanical vibrations, wind, fluid flow, solar and geothermal etc. using various mechanisms. Piezoelectric mechanism provides high power density of energy conversion from mechanical vibrations or wind into electric voltage or charge, however, due to the lower power output of these devices, many devices must be summoned in order to generate actual usable power for small scale electronic devices. In this paper, we have designed, developed, and extensively tested a multicylinder wind energy harvester that converts rotational motion into linear motion which further converts it into electric voltage using Faraday's law of electromagnetic induction. The multicylinder design and modified crank allow the device to output higher power while operating at lower wind speeds such as 2.4 m/s. Furthermore, this device included a rectifier to convert from AC to DC, a capacitor to clean the output signal, and a 5 V regulator that can be used to charge a USB connected smartphone or other smart devices. Under a regulated low wind speed of 2.4 m/s and across a 305 Ω load, the device had a rotational frequency of 0.76 Hz and a power output of 1.2 mW whereas at the wind speed of 4.9 m/s the rotational frequency was 7.25 Hz and the output 421.9 mW. At a rotational frequency of 6 Hz the device was used to charge a 3.7 V 46 mAh smart watch at 1% charge in 1.4 min. We also used an optimized 305 Ω load in wind speeds reaching 10.1 m/s in real world conditions at which point the harvesters' output peaked at 1.21 W resulting in a power density of 19.98 W/m3. Authors believe that these results are promising for understanding, investigating, and providing continuous power solutions to small scale smart electronic devices.

Investigation of active cell balancing performance for series connected lithium‐ion cells in electric vehicle applications

AbstractLithium‐ion batteries have a very wide application range. They can power up small electronic devices such as smart watches to larger electric vehicles. Due to its varied range of applications, they come in different packaging and in such battery packs, even when individual cell voltage exceeds by a few milli‐volts above 4.2 V, it may result in thermal runaway and explode the cell. During discharge cycle, cell imbalances hinder the use of battery to its full capacity. This in turn decreases the battery lifetime. The individual battery cells should be equalized on a regular basis to keep the imbalances to a minimum and to have a good battery life. The process of balancing the individual cell charges by measuring the cell state of charge (SoC) and its voltage in a battery pack is known as cell balancing. This paper details an active cell balancing technique that uses a buck converter for balancing a series connected battery pack of lithium‐ion cells. A buck converter along with a pair of MOSFET switches for each cell, one turned on for charging the cell and the other one turned on while discharging the cell is used in this experiment. An algorithmic model suitable for reconfigurable battery systems that measures the individual cell voltages and is developed for balancing a pack of series connected Li‐ion battery cells. The developed model is simulated using MATLAB for verifying its performance. A state of charge of 25% is maintained across the cells and when SoC value drops below this even a difference of 0.02% is sensed by the algorithm to initiate balancing function. This balancing is found to take 275 ms to balance three 3.7 V batteries and thus the model is found to respond faster. The results show that this method can self‐adaptively attain satisfactory performance within a limited equalizing period.

Reconfigurable dual‐band wireless power transfer (RDB‐WPT) system using meander line for near‐field WPT applications

SummaryIn this work, the reconfigurable dual‐band wireless power transfer (RDB‐WPT) system is proposed. The studied system allows to transfer power or data in two frequency bands. The first band is tuned from 1.4 to 1.7 GHz while the second band is fixed at 2.17 GHz. The receiver circuit (Rx) is identical to the transmitter circuit (Tx), and they are coupled in back‐to‐back. The feed line is extended with a stub for matching, and it is built on the top layer. The meander line and the rectangular DGS are placed on the ground. The prototype is fabricated with a compact size of 30 × 15 mm2 to be used in small portable electronic devices. The measured efficiencies are 95% at the average of the tuned band and 92% at 2.17 GHz. Good agreements are achieved between the simulation, theoretical studies, and measurements.

Self-Assembly of Polymer-Modified FePt Magnetic Nanoparticles and Block Copolymers.

The fabrication of nanocomposites containing magnetic nanoparticles is gaining interest as a model for application in small electronic devices. The self-assembly of block copolymers (BCPs) makes these materials ideal for use as a soft matrix to support the structural ordering of the nanoparticles. In this work, a high-molecular-weight polystyrene-b-poly(methyl methacrylate) block copolymer (PS-b-PMMA) was synthesized through anionic polymerization. The influence of the addition of different ratios of PMMA-coated FePt nanoparticles (NPs) on the self-assembled morphology was investigated using transmission electron microscopy (TEM) and small-angle X-ray scattering (SAXS). The self-assembly of the NPs inside the PMMA phase at low particle concentrations was analyzed statistically, and the negative effect of higher particle ratios on the lamellar BCP morphology became visible. The placement of the NPs inside the PMMA phase was also compared to theoretical descriptions. The magnetic addressability of the FePt nanoparticles inside the nanocomposite films was finally analyzed using bimodal magnetic force microscopy and proved the magnetic nature of the nanoparticles inside the microphase-separated BCP films.

Harnessing Energy for Wearables: A Review of Radio Frequency Energy Harvesting Technologies

Wireless energy harvesting enables the conversion of ambient energy into electrical power for small wireless electronic devices. This technology offers numerous advantages, including availability, ease of implementation, wireless functionality, and cost-effectiveness. Radio frequency energy harvesting (RFEH) is a specific type of wireless energy harvesting that enables wireless power transfer by utilizing RF signals. RFEH holds immense potential for extending the lifespan of wireless sensors and wearable electronics that require low-power operation. However, despite significant advancements in RFEH technology for self-sustainable wearable devices, numerous challenges persist. This literature review focuses on three key areas: materials, antenna design, and power management, to delve into the research challenges of RFEH comprehensively. By providing an up-to-date review of research findings on RFEH, this review aims to shed light on the critical challenges, potential opportunities, and existing limitations. Moreover, it emphasizes the importance of further research and development in RFEH to advance its state-of-the-art and offer a vision for future trends in this technology.