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Organic solar cells (OSCs) have emerged as a promising technology for renewable energy generation due to their low cost, lightweight, flexibility, and compatibility with roll-to-roll manufacturing. However, OSCs still face challenges in achieving high power conversion efficiency (PCE) due to various factors, including recombination loss. In this study, we investigated the effect of introducing a layer of eight atomic percent gadolinium-doped zinc oxide (Zn0.92Gd0.08O) between the poly(3-hexylthiophene) (P3HT): [6,6]-phenyl butyric acid methyl ester (PCBM) active layer and the fluorine-doped tin oxide (FTO) electrode of the OSC. The reference cell, which has an Au/P3HT:PCBM/ZnO/FTO structure, exhibits a PCE of 0.52%. Remarkably, when the Zn0.92Gd0.08O layer was inserted (Au/P3HT:PCBM/Zn0.92Gd0.08O/FTO), the PCE increased significantly to 3.42%, which is more than six times the increase. Through further analysis, we present that the insertion of the Zn0.92Gd0.08O layer induces spin polarization in the P3HT:PCBM layer, leading to enhanced charge transport and reducing the recombination rate. Based on the findings, it can be concluded that the Zn0.92Gd0.08O film can potentially improve OSC performance. [ABSTRACT FROM AUTHOR]

Lithium-ion battery is a type of rechargeable battery. A lithium-ion battery consists of several components, such as electrodes (anode and cathode), separators, and electrolytes. One factor that can affect a battery's performance is the quality of the electrodes. The commonly used anode consists of graphite powder. Currently, there is nanotechnology, namely the application of technology to make materials on the nanoscale (1-100 nm). The advantage of nanoparticle technology is its openness to be combined with other technologies, opening up opportunities to produce more perfect delivery systems. In this research, the production of lithium-ion batteries was carried out by adding nanoparticles as an anode. The nanoparticles used result from arc discharge synthesis with varying currents of 40A and 70A. The test results show that current variations in the arc-discharge synthesis process in the manufacture of lithium-ion battery anode nanoparticles affect the performance of lithium-ion batteries. Batteries using 70A nanoparticle anodes have a higher specific capacity than batteries using 40A nanoparticle anodes during chargedischarge. However, the specific capacity of the battery with nanoparticle anode is lower than that of the battery with graphite anode. When charging, the time needed for a battery that uses a 70A nanoparticle anode is shorter than a battery that uses a graphite anode and 40A nanoparticles. When discharging a battery that uses a 40A nanoparticle anode has a shorter time compared to a battery that uses a 70A nanoparticle and graphite anode.

The study focuses on optimizing standalone PV-battery systems for LED street lighting in Magetan Regency, Indonesia, emphasizing the importance of PV panels and lithium battery selection for energy efficiency. Minimizing energy not captured leads to effective, sustainable, and eco-friendly street lighting, reducing energy waste and promoting a greener urban environment. The optimization process involves choosing the appropriate PV panel size, battery capacity, and solar charge controller to maximize energy capture while meeting load requirements and design constraints. Solar resource assessment using PVGIS ensures system feasibility analysis. Simulation results reveal optimized PV panel peak power (200 Wp), battery capacity (1002 Wh), and a 16.67A MPPT solar charge controller. The average energy not captured is 144.21 Wh per month, showcasing the system’s efficiency. The discussion emphasizes the significance of this optimized configuration in enhancing energy capture and storage capacity, resulting in reliable and eco-friendly street lighting solutions.

This research develops an automatic feeder vessel for catfish farming. The aim is to increase the efficiency of feeding. In trials, the ship produced 113 grams of feed in 10 seconds and 716 grams in 60 seconds. Ship speed and radius affect GPS accuracy. The implementation of automatic feeding vessels in ponds worked well, following routes, providing feed according to the program, and transmitting data via IoT. This research contributes to overcoming the problem of equal distribution of feed in catfish farming with automatic feeders to increase the efficiency and productivity of aquaculture.

An induction motor's speed can be managed in a variety of ways using a Variable Frequency Drive (VFD). In this study, the speed control of an induction motor will be controlled by applying Indirect Field Oriented Control (IFOC) combined with Linear Quadratic Gaussian (LQG). Conventional LQG control is a linear controller; therefore, if the system's dynamic is high and over the linear boundary, the LQG performance will not be optimal. Therefore, Adaptive LQG (ALQG) is proposed. Fuzzy logic is used as an adaptive algorithm with low complexity and ease of implementation. The significance of this study lies in its endeavor to tackle the challenges associated with nonlinearities and high dynamics in induction motor control. The average performance of speed variation and load variation tests proves that ALQG is superior in terms of settling time and undershooting than PID and LQG. PID has the highest overshoot with the smallest Integral Absolute Error (IAE). In comparison, ALQG is superior to conventional LQG in terms of IAE with 3.59% lower. [ABSTRACT FROM AUTHOR]

The high demand for hydrogen has led to the development of various production methods. This study examines the use of synthetic and natural catalysts in the generation of hydrogen and biohydrogen. A bibliographic analysis was conducted using the VOSviewer and ScientoPy tools. The research focuses on hydrogen synthesis, purification, separation, and storage, based on the findings. Hydrogen and biohydrogen can be produced through processes such as reforming, decomposition, hydrolysis, gasification, photolysis, and fermentation. The most studied approach is natural gas steam reforming, using Ni and Ce as catalysts and Al₂O₃, Al₂O₄, and BaTiO₃ as support materials, resulting in a high turnover frequency (TOF) of 2880 h−1 and an average stability of 100 h. In contrast, ammonia borane (AB) hydrolysis with Pt/Co₃O₄ catalysts may achieve a high TOF of 15 times faster than steam methane reforming (SMR). Additionally, HY‐zeolite containing nickel has a maximum stability of 578 h. Enhancing hydrogen and biohydrogen generation could be achieved by incorporating two or more metals that work synergistically and by building hierarchical structures in zeolite. In photocatalysis, it is important to design catalysts that improve light absorption. Using activated natural zeolites in the gasification process (conventional, supercritical, or hydrothermal) requires various raw materials and advanced chemical processes, which poses challenges for future work. [ABSTRACT FROM AUTHOR]

In this digital age, most aspects of life require an electric supply. The availability of electrical power is very critical to maintaining the continuity of the system in various applications. To maintain system continuity, the Energy Monitoring and Control of an Automatic Transfer Switch (ATS) between the Grid and Solar Panel is proposed. The system consists of an Automatic Transfer Switch, Home Solar Power Plant, and Automatic Charging. The function of the monitoring system is to monitor the voltage, current, and power across the device, the operation mode of the ATS, and the State of Charge (SoC) of the battery. The control system is to control the operation mode of ATS according to the energy source selected by the user on the Internet of Things (IoT) interface. The results show that the system can successfully monitor solar panel conditions, AC output, and battery's State of Charge through Blynk IoT. The ATS works automatically with a switching delay of 20ms to 26ms, while on the user's command, the average switching delay is 303.33ms to activate the relay and 185ms to deactivate the relay. [ABSTRACT FROM AUTHOR]

Three-phase induction motors are the main drivers of the industrial world because of their low price and good reliability. However, this type of motor does not have built-in speed control. These problems can be overcome by utilizing the Variable Frequency Drive (VFD) inverter. This research investigates the induction motor's characteristics in every load condition and combines a VFD inverter with an external speed controller based on Arduino. The motor is mounted on a Prony brake testbed frame to measure the motor's torque and mechanical power. The test results show the highest torque value obtained is 0.57 Nm, and the highest output power value is 0.042 kW. The motor cannot maintain the setpoint speed after loading in the open-loop control system. Meanwhile, the closed-loop control system has been successfully implemented, and the motor can return the speed to the setpoint value after loading, with an average settling time of 14.67 seconds. [ABSTRACT FROM AUTHOR]

This work presents a design and implementation an information system called LoRa-Building Energy Management System (Lo-BEMS). This research proposes an engaging data transmission (read and write), that combines the HTTP and MQTT protocols using third party broker that has monitor and control features for energy usages. Data retrieving uses single LoRa modulation and delivery to the Application Programming Interface (API) in Laravel Framework will then be stopped by the system and stored in the database. The development of this system uses the Rapid Application Development (RAD) method and the Laravel Frameworks. The black-box, UAT, and performance validation test results showed that the information system was running properly and following the objectives. [ABSTRACT FROM AUTHOR]

Trivalent metal-doped TiO2 thin films have been extensively investigated in gas sensor applications. The trivalent metal dopants are Al, Y and Gd. The trilayer fabrication of a gas sensor consists of a thin film, sputtered TiO2 and Au nanoparticles. The characteristics of the gas sensing properties are strongly correlated with the annealing temperature, film thickness, type of doping and deposition method. The subsequent properties are presented - the crystalline structure, grain size, roughness, strain, stress and defects. Thin films have been developed with concentrations of O2 gas up to 10 sccm. A response time for O2 gas in milliseconds was obtained at room temperature. Al doped TiO2 thin film have a faster response time operating at room temperature compared with other thin films. Oxygen vacancy defects also contribute to the speed of the response time for a gas sensor. [ABSTRACT FROM AUTHOR]

This work addresses the design, fabrication, and implementation of an RF energy harvester 2.45 GHz using a compact rectenna. Our proposed rectenna focuses on development of an antenna array and rectifier circuit. The proposed rectenna is fabricated using FR4 substrate with its overall size of 12.24 cm × 18.17 cm with a thickness of 1.6 mm. The measured results show that a 10 dB bandwidth covering in 2374-2549 MHz (175 MHz) with center frequency 2415 MHz at S11 of −18.2 dB. There is a bandwidth enhancement of 57.6% compared to the single antenna. Gaining of the antenna array is 6 dB that is double a single antenna gain. Spatial diversity technique in antenna array yields a bigger antenna gain thereby increasing the received power level. Experimental measurements are carried out that the rectenna is placed indoor (LOS) at 5 m and outdoor (NLOS) at 15 m. Furthermore, we also explore the rectifier circuit that to maximize the output voltage. The received RF power that transmitted from WiFi router is −55 dBm (0.15 nW/cm2) at 5 m and −59 dBm (0.06 nW/cm2) at 15 m, respectively. The output voltages are achieved that 1092.5 mV at a distance of 5 m (LOS) and 5.48 mV at a distance of 15 m (NLOS). The highest RF-DC conversion efficiency of our proposed rectenna reaches 77.6%. The rectenna potentially meets all requirements to power up the IoT applications. [ABSTRACT FROM AUTHOR]

Solution processible poly(4-vinylphenol) is employed as a transistor dielectric material for low cost processing on flexible substrates at low temperatures. A 6,13-bis (triisopropylsilylethynyl) (TIPS) pentacene–graphene hybrid semiconductor is drop cast to fabricate bottom-gate and bottom-contact field-effect transistor devices on flexible and glass substrates under an ambient air environment. A few layers of graphene flakes increase the area in the conduction channel, and form bridge connections between the crystalline regions of the semiconductor layer which can change the surface morphology of TIPS pentacene films. The TIPS pentacene–graphene hybrid semiconductor-based organic thin film transistors (OTFTs) cross-linked with a poly(4-vinylphenol) gate dielectric exhibit an effective field-effect mobility of 0.076 cm2 V−1 s−1 and a threshold voltage of −0.7 V at Vgs = −40 V. By contrast, typical TIPS pentacene shows four times lower mobility of 0.019 cm2 V−1 s−1 and a threshold voltage of 5 V. The graphene/TIPS pentacene hybrids presented in this paper can enhance the electrical characteristics of OTFTs due to their high crystallinity, uniform large-grain distribution, and effective reduction of crystal misorientation of the organic semiconductor layer, as confirmed by x-ray diffraction spectroscopy, atomic force microscopy, and optical microscopy studies. [ABSTRACT FROM AUTHOR]

High-performance pentacene-based thin-film transistors and inverters with solution-processed barium titanate (BTO) insulators are demonstrated. The current–voltage characteristics of the transistors show high mobility of 9.53 \cm^2\V^-1\s^-1 at smaller VG = -\3.5\ \V and VD = -\5\ \V, a low threshold voltage of -1.5 V, and a subthreshold slope of 599 mV/dec. Large grain and small crystalline sizes are observed from atomic force microscopy images and X-ray diffraction analysis of pentacene films. The results are verified through Raman spectroscopy and a theoretical Marcus–Hush equation to understand the higher intermolecular coupling, resulting in easier carrier transports in pentacene molecules. In order to investigate the behavior of high-permittivity materials of BTO insulators in a logic circuit, simple and low-operating-voltage inverters are fabricated, and the gain is approximately 8.76 under a small operating voltage range from 0 to -5 V. [ABSTRACT FROM PUBLISHER]

Barium-doped \TiO2 films deposited on GaN layers at low temperature through a simple liquid phase deposition method is investigated. The use as a gate dielectric in AlGaN/GaN metal–oxide–semiconductor high-electron mobility transistors (MOSHEMTs) is also demonstrated. The electrical characteristics of the MOS structure on n-doped GaN show that the leakage current density is about \5.09 \times \10^-9\ \A/cm^2 at 1 MV/cm, and the breakdown field is more than 13 MV/cm. The maximum drain current density of the AlGaN/GaN MOSHEMTs is higher than that of HEMTs, in which a wider gate voltage swing and a lower subthreshold swing (110 mV/decade) are obtained. The gate leakage current density is significantly improved, and the gate pulse measurement shows that the current collapse is more suppressed for MOSHEMTs. [ABSTRACT FROM PUBLISHER]

Pentacene-based organic thin-film transistors with solution-processed barium zirconate titanate dielectric layers are demonstrated. According to the programming/erasing operations, the devices exhibited memory characteristics, such as reversible threshold voltage shifts and nondestructive readout. In addition, the reliability of the memory devices was confirmed by data retention time and repeated switching cycles' endurance testing. In addition, the possible mechanism of the memory effect was also discussed. These results suggest that the devices could potentially be applied to nonvolatile memory applications in organic electronics. [ABSTRACT FROM AUTHOR]

Pentacene-based organic thin-film transistors (OTFTs) with solution-processed barium titanate (\Ba1.2\Ti0.8\O3) as a gate insulator are demonstrated. The electrical properties of pentacene-based TFTs show a high field-effect mobility of 8.85 \cm^2 \cdot \V^-1 \cdot \s^-1, a low threshold voltage of -1.89 V, and a low subthreshold slope swing of 310 mV/decade. The chemical composition and binding energy of solution-processed barium titanate thin films are analyzed through X-ray photoelectron spectroscopy. The matching surface energy on the surface of the barium titanate thin film is 43.12 \mJ \cdot \m^-2, which leads to Stranski–Krastanov mode growth, and thus, high mobility is exhibited in pentacene-based TFTs. [ABSTRACT FROM AUTHOR]

Pentacene-based organic thin-film transistors with solution-process hafnium oxide (HfO∞) as gate insulating layer have been demonstrated. The solution-process HfO∞ could not only exhibit a high-permittivity (K = 11) dielectric constant but also has good dielectric strength. Moreover, the root-mean-square surface roughness and surface energy (γS) on the surface of the HfO∞ layer were 1.304 nm and 34.24 mJ/cm2, respectively. The smooth, as well as hydrophobic, surface of HfO∞ could facilitate the direct deposition of the pentacene film without an additional polymer treatment layer, leading to a high field-effect mobility of 3.8 cm2/(V ∙ s). [ABSTRACT FROM AUTHOR]