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This paper presents innovations in green electronic and computing technologies. The importance and the status of the main subjects in green electronic and computing technologies are presented in this paper. In the last semicentennial, the planet suffered from rapid changes in climate. The planet is suffering from increasingly wild storms, hurricanes, typhoons, hard droughts, increases in seawater height, floods, seawater acidification, decreases in groundwater reserves, and increases in global temperatures. These climate changes may be irreversible if companies, organizations, governments, and individuals do not act daily and rapidly to save the planet. Unfortunately, the continuous growth in the number of computing devices, cellular devices, smartphones, and other smart devices over the last fifty years has resulted in a rapid increase in climate change. It is severely crucial to design energy-efficient "green" technologies and devices. Toxic waste from computing and cellular devices is rapidly filling up landfills and increasing air and water pollution. This electronic waste contains hazardous and toxic materials that pollute the environment and affect our health. Green computing and electronic engineering are employed to address this climate disaster. The development of green materials, green energy, waste, and recycling are the major objectives in innovation and research in green computing and electronics technologies. Energy-harvesting technologies can be used to produce and store green energy. Wearable active sensors and metamaterial antennas with circular split ring resonators (CSSRs) containing energy-harvesting units are presented in this paper. The measured bandwidth of the matched sensor is around 65% for VSWR, which is better than 3:1. The sensor gain is 14.1 dB at 2.62 GHz. A wideband 0.4 GHz to 6.4 GHz slot antenna with an RF energy-harvesting unit is presented in this paper. The Skyworks Schottky diode, SMS-7630, was used as the rectifier diode in the harvesting unit. If we transmit 20 dBm of RF power from a transmitting antenna that is located 0.2 m from the harvesting slot antenna at 2.4 GHz, the output voltage at the output port of the harvesting unit will be around 1 V. The power conversion efficiency of the metamaterial antenna dipole with metallic strips is around 75%. Wearable sensors with energy-harvesting units provide efficient, low-cost healthcare services that contribute to a green environment and minimize energy consumption. The measurement process and setups of wearable sensors are presented in this paper. [ABSTRACT FROM AUTHOR]

Organic electroactive materials, particularly semiconducting polymers, are at the forefront of emerging organic electronics. Among the plethora of unique features, the possibility to formulate inks out of these materials is particularly promising for the large‐scale manufacturing of electronics at lower cost on a variety of soft substrates. While solution deposition of semiconducting materials is promising for developing printed electronics, the environmental footprint of the materials and related devices needs to be considered to achieve sustainable manufacturing. Towards the development of greener printed electronics, this work investigates the utilization of a non‐toxic, environmentally‐friendly solvent, namely branched polyethylene (BPE), to formulate semiconducting inks. Focusing on a diketopyrrolopyrrole‐based (DPP) semiconducting polymer, shellac as dielectric, and BPE as the solvent, solutions were prepared in different concentrations and their rheological properties were characterized. Then, printing on polyethylene terephthalate (PET) substrates using two different techniques was performed to fabricate organic field‐effect transistors (OFETs). Both printing techniques yielded OFETs with good performance and device characteristics, averaging approximately 10−2 and 10−4 cm2 V−1 s−1, respectively, for slot‐die coating and direct‐ink writing deposition. Notably, despite some difference in threshold voltages, OFETs produced via slot‐die coating and direct‐ink writing showed comparable charge mobilities to previously reported OFETs prepared from similar materials, particularly those prepared on silicon dioxide wafers. Overall, this work confirms the suitability of BPE to formulate semiconducting inks to develop printed electronics in a greener manner. The printing methodology developed in this work also open new avenues for the design of functional printed electronics and related technologies. [ABSTRACT FROM AUTHOR]

Extensive research into green technologies is driven by the worldwide push for eco‐friendly materials and energy solutions. The focus is on synergies that prioritize sustainability and environmental benefits. This study explores the potential of abundant, non‐toxic, and sustainable resources such as paper, lignin‐enriched paper, and cork for producing laser‐induced graphene (LIG) supercapacitor electrodes with improved capacitance. A single‐step methodology using a CO2 laser system is developed for fabricating these electrodes under ambient conditions, providing an environmentally friendly alternative to conventional carbon sources. The resulting green micro‐supercapacitors (MSCs) achieve impressive areal capacitance (≈7–10 mF cm−2) and power and energy densities (≈4 μW cm‐2 and ≈0.77 µWh cm−2 at 0.01 mA cm−2). Stability tests conducted over 5000 charge–discharge cycles demonstrate a capacitance retention of ≈80–85%, highlighting the device durability. These LIG‐based devices offer versatility, allowing voltage output adjustment through stacked and sandwich MSCs configurations (parallel or series), suitable for various large‐scale applications. This study demonstrates that it is possible to create high‐quality energy storage devices based on biodegradable materials. This development can lead to progress in renewable energy and off‐grid technology, as well as a reduction in electronic waste. [ABSTRACT FROM AUTHOR]

Among the solid‐state lighting technologies, OLEDs occupy a prominent position for the high efficiencies associated with the low CO2 emissions. In line with the recent studies aimed at designing sustainable and biodegradable devices, herein we report on the synthesis of a series of iridium(III) complexes featuring, as β‐diketone ligands, curcumin and 6‐dehydrogingerdione, two natural compounds found in the rhizome of Curcuma longa and Zingiber officinale. To improve the solubility of both the ligands and prevent the aggregation of the complexes, oleoyl residues were inserted on the phenolic −OH groups. The resulting complexes exhibited a green emission with quantum yields as high as 2.8 % (relative to fluorescein). OLED devices were fabricated by using, as emitting layer, a host‐guest blend of the iridium complex in 4,4'‐bis(N‐carbazolyl)‐1,1'‐biphenyl (CBP). The morphological analysis revealed that thin films of the emitting layer were homogeneous. The devices fabricated with iridium complexes from 6‐dehydrogingerdione exhibited higher luminance, efficiency and power efficiency with respect to the corresponding devices obtained from curcumin; also the functionalization of the β‐diketone unit with the oleoyl residue proved to increase significantly the performance of the device. Overall, these data suggest that aggregation is a key factor that compromise the performances of the corresponding OLEDs. [ABSTRACT FROM AUTHOR]

Papertronics introduce a sustainable, cost‐effective revolution in electronics, especially for the Internet of Things. This research overcomes the traditional challenges of paper's porosity, which has impeded electronic component fabrication and performance. A novel approach that harnesses paper's natural capillary action, combined with hydrophobic wax patterning, to achieve precise vertical integration of electronic components is introduced. This method marks a significant departure from conventional surface deposition techniques. This study demonstrates the successful creation of tunable resistors, capacitors, and field‐effect transistors, embedded within a single sheet of paper. Contrary to previous assumptions that impeded the use of paper, its rough and porous texture as a strategic advantage, facilitating the precise fabrication of intricate electronic components is leveraged. Machine learning algorithms play an important role in predicting and enhancing the performance of these papertronic components. This innovation facilitates the development of compact printed circuit boards with increased circuit density, enabling the integration of diverse analog and digital circuits in either single or multi‐layer paper formats. The resulting papertronic systems exceed performance benchmarks, offering eco‐friendly disposal through biodegradability or incineration. These breakthroughs establish papertronics as a feasible, eco‐friendly alternative in the electronics industry, permitting widespread adoption and continuous innovation in sustainable electronic solutions. [ABSTRACT FROM AUTHOR]

The underutilization of digestate-derived polymers presents a pressing environmental concern as these valuable materials, derived from anaerobic digestion processes, remain largely unused, contributing to pollution and environmental degradation when left unutilized. This study explores the recovery and utilization of biodegradable polymers from biomass anaerobic digestate to enhance the performance of solar photovoltaic (PV) cells while promoting environmental sustainability. The anaerobic digestion process generates organic residues rich in biodegradable materials, often considered waste. However, this research investigates the potential of repurposing these materials by recovering and transforming them into high-quality coatings or encapsulants for PV cells. The recovered biodegradable polymers not only improve the efficiency and lifespan of PV cells but also align with sustainability objectives by reducing the carbon footprint associated with PV cell production and mitigating environmental harm. The study involves a comprehensive experimental design, varying coating thickness, direct normal irradiance (DNI) (A), dry bulb temperature (DBT) (B), and relative humidity (C) levels to analyze how different types of recovered biodegradable polymers interact with diverse environmental conditions. Optimization showed that better result was achieved at A = 8 W/m2, B = 40 °C and C = 70% for both the coated material studied. Comparative study showed that for enhanced cell efficiency and cost effectiveness, EcoPolyBlend coated material is more suited however for improving durability and reducing environmental impact NanoBioCelluSynth coated material is preferable choice. Results show that these materials offer promising improvements in PV cell performance and significantly lower environmental impact, providing a sustainable solution for renewable energy production. This research contributes to advancing both the utilization of biomass waste and the development of eco-friendly PV cell technologies, with implications for a more sustainable and greener energy future. This study underscores the pivotal role of exploring anaerobic digestate-derived polymers in advancing the sustainability and performance of solar photovoltaic cells, addressing critical environmental and energy challenges of our time.Please confirm if the author names are presented accurately and in the correct sequence (given name, middle name/initial, family name). Author 7 Given name: [Ashok] Last name [Kumar Yadav]. Also, kindly confirm the details in the metadata are correct.correct [ABSTRACT FROM AUTHOR]

Investigating biodegradable and biocompatible materials for electronic applications can lead to tangible outcomes such as developing green-electronic devices and reducing the amount of e-waste. The proposed emulsion-based conducting ink formulation takes into consideration circular economy and green principles throughout the entire process, from the selection of materials to the production process. The ink is formulated using the biopolymer polylactic acid dissolved in a sustainable solvent mixed with water, along with conductive carbon nanotubes (CNTs) and silver flakes as fillers. Hybrid conductive fillers can lower the percolation threshold of the ink and the production costs, while maintaining excellent electrical properties. The coating formed after the deposition of the ink, undergoes isothermal treatment at different temperatures and durations to improve its adhesion and electrical properties. The coating's performance was evaluated by creating an eight-finger interdigitated sensor using a Voltera PCB printer. The sensor demonstrates exceptional performance when exposed to various loading and unloading pressures within the 0.2–500.0 kPa range. The results show a consistent correlation between the change in electrical resistance and the stress caused by the applied load. The ink is biodegradable in marine environments, which helps avoiding its accumulation in the ecosystem over time. [ABSTRACT FROM AUTHOR]

Electronics and mechatronics waste is an exponentially increasing environmental issue, especially for wearable devices, due to their widespread diffusion into society and short life cycle. To promote their enormous benefits (e.g., in assisting visually impaired individuals) in a sustainable way, biobased and/or biodegradable organic materials should be used instead of traditional components. This manuscript presents a multidisciplinary approach, which bridges materials science and mechatronics, to propose the first ECO‐friendly wearable vibroTACtile device (Eco‐Tac). The design of Eco‐Tac includes integration on a cotton t‐shirt through a novel biodegradable conductive ink forming electrical tracks, a flexible commercially available solar panel, and the vibrotactile haptic device itself. The ink comprises a green solvent, anisole, a soft polybutylene adipate terephthalate biodegradable binder, and conductive nanocarbon materials. The device case is a biodegradable biocomposite. As such, the feasibility of using a sustainable energy source to supply power to the device and the possibility of using biodegradable materials in its manufacturing are demonstrated. An experiment with 20 blindfolded subjects is conducted, reporting the device's potential for assistance in manipulation tasks. Overall, the results of this work represent the first significant step toward the creation of wearable and sustainable haptic devices with green electronics and mechatronics approaches. [ABSTRACT FROM AUTHOR]

The biodegradable electronics are on the rise, not just due to their role in medical implants, but also because of their eco‐friendly attributes. A variety of methods, including transfer printing, have been employed to integrate inorganic electronics onto biodegradable polymer substrates. However, the use of expensive materials, multiple intermediary steps, and labor‐intensive procedures can undermine their environment‐friendly benefits. Here, a straightforward yet efficient fabrication method is introduced for creating high‐performance biodegradable electronic devices. This method leverages the controlled adhesion between the biodegradable device and substrate using self‐assembled monolayers of octadecyltrichlorosilane. Mechanical and thermal analyses based on scratch tests and time‐domain thermoreflectance quantify the adhesion by adjusting the packing density of octadecyltrichlorosilane. Controlled adhesion allows the photolithography process without delamination while facilitating easy delamination during transfer printing. The authors demonstrate the direct fabrication of electronics consisted of inorganic materials (Mg, Zn, SiO2, Si nanomembrane) on wafers and transfer‐printing onto polymer substrates via a single transfer step. This streamlined approach enables wafer‐scale fabrication of biodegradable electronics, highlighting its potential for mass manufacturing. Pilot conceptual demonstration of mass‐produced edible hydration sensors and their application in salivation measurement through in vivo model show the potential capability of proposed fabrication method in the use of practical level. [ABSTRACT FROM AUTHOR]

With the increase in demand for low-carbon technology, green raw materials, and comfortable heating, academia and industry have paid considerable attention to cellulose-based electrothermal composites. This attention owes to the fact that cellulose is a versatile, abundant, low-cost, and sustainable material with beneficial properties. Here, we develop a novel strategy for fabricating flexible, transparent electrothermal heaters that are composed of both silver nanowire (AgNW)/poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) electrothermal composites and a regenerated cellulose (RC) matrix. The AgNWs were spin-coated onto glass substrates and easily transferred onto an RC surface through the coagulation and regeneration of the cellulose solution. PEDOT:PSS was coated onto the AgNW-coated RC matrix to improve the electrical and electrothermal properties of the film heaters. The PEDOT:PSS/AgNW/RC composite films demonstrated an excellent optical transmittance of 73.8% at 550 nm and a low sheet resistance of 11.2 Ω/sq. These composite heaters also exhibited a rapid heating response, uniform heat distribution, excellent heat generation, and robust structural stability. These electrothermal composites made from earth-abundant, low cost, and recyclable materials have great potential for green, flexible, transparent film heaters. [ABSTRACT FROM AUTHOR]

Sensors and transducers enable the robots' movements and interactions with humans and the environment. Particularly, tactile and motion sensors, even those inspired by the human skin, often miss many of its essential features. Indeed, the materials that constitute such sensors are often rigid and lack self‐healing and biodegradability. Furthermore, the large‐scale diffusion of these technologies propelled by robots spread in many aspects of the lives, from industrial to household settings, contributes heavily to the electronic and robotic waste problem. Recycling strategies for materials for robotics sensors are thus pivotal for future development. This work proposes self‐healable, recyclable, and biodegradable electrically conductive coatings. These coatings are based on conductive inks that combine graphene nanoplatelets and carbon nanofibers with a soft biodegradable vitrimer binder and are realized by spray coating. The use of the vitrimer ensures satisfying adhesion to diverse substrates, flexibility, conformability, self‐healing, and recyclability of the conductive coating. This material is a sustainable alternative to standard conductive inks for flexible electronics and soft robotics. Indeed, tests for the live monitoring of SoftHand3, the grasping system of many worldwide diffused robots, have yielded promising results. The use of biodegradable ingredients and the possibility of recycling makes it an appealing material to face the sustainability issue of today's electronics and robotics. [ABSTRACT FROM AUTHOR]

In light of the growing concern for environmental protection and the alarming amount of waste produced due to hygiene regulations, this study suggests a biodegradable and eco-friendly solution that could make a significant contribution to the preservation of our planet. The developed solution was based on a polyhydroxybutyrate/polyhydroxyvalerate biopolymer, which has been tested regarding its physicochemical parameters and possible use in printed electrically conductive structures. Graphene nanoplatelets have been used as the conductive functional phase, due to literature reports of their potential use in biomedical applications and due to the potential of providing cytocompatibility in electrical structures by carbon nanomaterials. Prepared composites have been spray-coated onto PET film and paper substrates and then subjected to electrical, adhesion and optical measurements. In order to establish the conductivity of the developed composite, its resistance, layer thickness and surface topography were measured. Optical parameters have been specified using scanning electron microscopy (SEM) imaging and spectrophotometry. The conducted research opens a wide path for the use of the polyhydroxybutyrate/polyhydroxyvalerate biopolymer with graphene nanoplatelets in biomedical applications, ensuring good conductivity, biocompatibility and stability. [ABSTRACT FROM AUTHOR]

Despite advances in soft, sticker‐like electronics, few efforts have dealt with the challenge of electronic waste. Here, this is addressed by introducing an eco‐friendly conductive ink for thin‐film circuitry composed of silver flakes and a water‐based polyurethane dispersion. This ink uniquely combines high electrical conductivity (1.6 × 105 S m−1), high resolution digital printability, robust adhesion for microchip integration, mechanical resilience, and recyclability. Recycling is achieved with an ecologically‐friendly processing method to decompose the circuits into constituent elements and recover the conductive ink with a decrease of only 2.4% in conductivity. Moreover, adding liquid metal enables stretchability of up to 200% strain, although this introduces the need for more complex recycling steps. Finally, on‐skin electrophysiological monitoring biostickers along with a recyclable smart package with integrated sensors for monitoring safe storage of perishable foods are demonstrated. [ABSTRACT FROM AUTHOR]

Green electronics made from degradable materials have recently attracted special attention, because electronic waste (e‐waste) represents a serious threat to the environment and to human health worldwide. Among the novel materials used for sustainable technologies, nanocelluloses containing at least 1D in the nanoscale range (1–100 nm) have been widely exploited for various industrial applications owing to their inherent properties, such as biodegradability, mechanical strength, thermal stability, and optical transparency. This review highlights recent advances in research on the development of patterns for conductive material on nanocellulose substrates for use in high‐performance green electronics. The advantages of nanocellulose substrates compared to conventional paper substrates for advanced green electronics are discussed. Importantly, this review emphasizes various fabrication strategies for producing conductive patterns on different types of nanocellulose‐based substrates, such as cellulose nanofiber (CNF), (2,2,6,6‐tetramethylpiperidin‐1‐yl)oxyl(TEMPO)‐oxidized CNF, regenerated cellulose, and bacterial cellulose. In the latter part of this review, emerging engineering applications for green electronics such as circuits, transistors/antennas, sensors, energy storage systems, and electrochromic devices are further discussed. [ABSTRACT FROM AUTHOR]

Four pinaceae pine resins analyzed in this study: black pine, shore pine, Baltic amber, and rosin demonstrate excellent dielectric properties, outstanding film forming, and ease of processability from ethyl alcohol solutions. Their trap‐free nature allows fabrication of virtually hysteresis‐free organic field effect transistors operating in a low voltage window with excellent stability under bias stress. Such green constituents represent an excellent choice of materials for applications targeting biocompatibility and biodegradability of electronics and sensors, within the overall effort of sustainable electronics development and environmental friendliness. [ABSTRACT FROM AUTHOR]

Printing technologies have emerged as a viable method for the fabrication of various electronic components, including sensors, actuators, energy harvesters, thin-film transistors and circuits, as well as antennas. However, printing processes have limitations in terms of surface roughness and thickness. Printing conductive structures on novel substrates, such as cellulose-based sustainable paper, also leads to further challenges linked to the high surface porosity and ink carrier absorption. Herein, the variability of paper-based printed antenna performance due to different printing processes, ink carrier absorption, and temperature is investigated. The resonance frequency and gain of different printed antennas (e.g., screen, inkjet, and dispense-printed) are compared in terms of surface roughness, thickness, and resonance frequency. Screen-printed antennas show better performance compared to other printed antennas. The results show that the resonance frequency of antenna shifts 20, 30, and 50 MHz for screen printed, dispense printed, and inkjet printed respectively, from the nominal 2.6 GHz. In the case of the inkjet-printed antenna, a clear effect of skin depth is observed, due to the 0.91 μm thickness. Furthermore, it is demonstrated that the permittivity/dielectric constant of the paper substrate is significantly influenced by ink carrier absorption and temperature variance. [ABSTRACT FROM AUTHOR]

This article reviews the recent advances in the field of batteryless near-field communication (NFC) sensors for chemical sensing and biosensing. The commercial availability of low-cost commercial NFC integrated circuits (ICs) and their massive integration in smartphones, used as readers and cloud interfaces, have aroused great interest in new batteryless NFC sensors. The fact that coil antennas are not importantly affected by the body compared with other wireless sensors based on far-field communications makes this technology suitable for future wearable point-of-care testing (PoCT) devices. This review first compares energy harvesting based on NFC to other energy-harvesting technologies. Next, some practical recommendations for designing and tuning NFC-based tags are described. Power transfer is key because in most cases, the energy harvested has to be stable for several seconds and not contaminated by undesired signals. For this reason, the effect of the dimensions of the coils and the conductivity on the wireless power transfer is thoroughly discussed. In the last part of the review, the state of the art in NFC-based chemical and biosensors is presented. NFC-based tags (or sensor tags) are mainly based on commercial or custom NFC ICs, which are used to harvest the energy from the RF field generated by the smartphone to power the electronics. Low-consumption colorimeters and potentiostats can be integrated into these NFC tags, opening the door to the integration of chemical sensors and biosensors, which can be harvested and read from a smartphone. The smartphone is also used to upload the acquired information to the cloud to facilitate the internet of medical things (IoMT) paradigm. Finally, several chipless sensors recently proposed in the literature as a low-cost alternative for chemical applications are discussed. [ABSTRACT FROM AUTHOR]

A green textile‐based conductor with controllable electrical resistance change with deformation and transiency (i.e., dissolution in water) will be the holy grail in wearable electronics since it can satisfy divergent needs with a single solution and be sustainable simultaneously. Nevertheless, designing such material is challenging since opposite requirements shall be satisfied. To solve such a problem, cotton is functionalized using conductive inks made of graphene or carbon nanofiber, a biodegradable polyvinyl alcohol binder, and environmentally friendly solvents. The electrical resistance shows an anisotropic response to bending depending on the composition of the coating and the stress direction, functioning either as a deformable compliant electrode or a tunable piezoresistor. Indeed, it can withstand thousands of bending cycles with a change in resistance of less than 5% or change its resistance by many orders of magnitude with the same deformation thanks to the combination of cotton twill and different nanofillers. A simple modification in the binder composition adding waterborne polyurethane allows the coating to go from entirely transient in water within minutes to withstanding simulated washing cycles for hours without losing its electrical conductivity. This green versatile conductor may serve opposing needs by altering the material composition and the deformation direction. [ABSTRACT FROM AUTHOR]

The Internet of Things (IoT) is gaining more and more popularity and it is establishing itself in all areas, from industry to everyday life. Given its pervasiveness and considering the problems that afflict today's world, that must be carefully monitored and addressed to guarantee a future for the new generations, the sustainability of technological solutions must be a focal point in the activities of researchers in the field. Many of these solutions are based on flexible, printed or wearable electronics. The choice of materials therefore becomes fundamental, just as it is crucial to provide the necessary power supply in a green way. In this paper we want to analyze the state of the art of flexible electronics for the IoT, paying particular attention to the issue of sustainability. Furthermore, considerations will be made on how the skills required for the designers of such flexible circuits, the features required to the new design tools and the characterization of electronic circuits are changing. [ABSTRACT FROM AUTHOR]

The growing usage and consumption of electronics‐integrated items into the daily routine has raised concerns on the disposal and proper recycling of these components. Here, a fully sustainable and green technology for the fabrication of different electronics on fruit‐waste derived paper substrate, is reported. The process relies on the carbonization of the topmost surface of different cellulose‐based substrates, derived from apple‐, kiwi‐, and grape‐based processes, by a CO2 laser. By optimizing the lasing parameters, electronic devices, such as capacitors, biosensors, and electrodes for food monitoring as well as heart and respiration activity analysis, are realized. Biocompatibility tests on fruit‐based cellulose reveal no shortcoming for on‐skin applications. The employment of such natural and plastic‐free substrate allows twofold strategies for electronics recycling. As a first approach, device dissolution is achieved at room temperature within 40 days, revealing transient behavior in natural solution and leaving no harmful residuals. Alternatively, the cellulose‐based electronics is reintroduced in nature, as possible support for plant seeding and growth or even soil amendment. These results demonstrate the realization of green, low‐cost and circular electronics, with possible applications in smart agriculture and the Internet‐of‐Thing, with no waste creation and zero or even positive impact on the ecosystem. [ABSTRACT FROM AUTHOR]

Increasing environmental concerns raised by the accumulation of electronic waste draws attention to the development of sustainable materials for short‐lived electronics. In this framework, printed capacitive humidity sensors and temperature resistive detectors composed exclusively of biodegradable materials: shellac, carbon‐derived particles, and egg‐albumin are reported. The sensor platform comprises interdigitated electrodes serving as a capacitive transducer for humidity sensing, and a serpentine used as a resistive temperature detector. Both the interdigitated and serpentine electrodes are manufactured by screen‐printing carbon ink on a shellac substrate. The humidity sensors are constructed by drop‐coating egg albumin on the interdigitated carbon electrodes and the temperature detector is prepared by encapsulating the serpentine design with shellac. Shellac is shown to be a biodegradable alternative to hydrophilic cellulose‐derived substrates, with the capacitive humidity sensors demonstrating a sensitivity of 0.011% RH−1. The response and recovery times on shellac are 12 and 20 times faster than on cellulose‐based substrate, and the serpentine resistive temperature detectors have a temperature coefficient of 5300 ppm K−1. At the end of their service‐life, the sensors produced are home compostable and can be environmentally friendly disposed, potentially enabling their future use for sustainable and environmentally friendly smart‐packaging, agricultural sensing, or point‐of‐care testing. [ABSTRACT FROM AUTHOR]

Sunflower‐inspired sun‐tracking systems have been arousing intensive investigations owing to their benefits to improve the efficiency of solar energy collection. Photodetector based on photosensitive semiconductors is a mainstream choice in the sun‐tracking system, which directs solar collectors always facing the sun. However, photosensitive semiconductors to date have usually hidden the disadvantages of environmental pollution after disposal. As for these problems, this work develops a green ionic liquid‐based photodetector, which displays reliable electrical feedback in response to sunlight. This liquid sunlight detector can be readily recycled with less laborious and costly operations. It obeys a light sensing mechanism of photothermal conversion, so it does not involve the problems related to dark current and light saturation. As a practical demonstration, the ionic liquid‐based photodetector is assembled into a sun‐tracking system, which successfully pursues the moving sun in a real time. When such a sun‐tracking system is in tandem with optical fiber concentrator, sunlight can be efficiently collected and transported to desired position. [ABSTRACT FROM AUTHOR]

Hydroxypropyl cellulose (HPC) is a commercially available and biodegradable cellulose derivative, which is known to self‐assemble into chiral nematic liquid crystal phases in water. These features, including liquid crystal‐induced selective reflections in the visible range, make HPC an ideal biopolymer host material for dynamic structural color‐shifting materials. Herein, HPC is used as a starting matrix material and found that, by adding carbon nanotubes (CNT) to an aqueous dispersion of HPC, the color saturation can be improved without influencing the structural color formation and simultaneously conferring electrical conductivity to the material. Additionally, up to 0.4 wt% of cellulose nanofibrils (CNF) can be added to control and tune the rheological properties of the suspension allowing for 3D printability while also maintaining the structural colors. The HPC‐CNT‐CNF printed composite materials show application for flexible color‐changing devices in the form of a dual readout optical and resistive strain sensor and is used as the active material in a dynamic seven‐segment color display. This multipurpose color‐changing material has the potential to be used in the creation of eco‐friendly visual intelligent devices and biodegradable user interfaces and, as such, contributes to the advancement of the field of sustainable and green electronics. [ABSTRACT FROM AUTHOR]

Nature and its biodiversity provide academics with a plethora of research topics, including the development of dielectric layers based on natural compounds that do not require any purification process for use in electronic equipments. Nevertheless, the properties of natural substances must then be investigated, and a suitable low-cost coating technique must be established. This study looks at the physicochemical behavior of khaya gum (KG) which is a biopolymer derived from khaya Senegalese tree exudates. In the form of powder, X-ray diffraction and scanning electron microscopy analyses of khaya gum revealed an amorphous structure and a slightly rough surface morphology with apparent wrinkles, respectively. The presence of oxides such as Al2O3, CaO, SiO2, as well as a high concentration of CuO, were disclosed by X-ray fluorescence data. Furthermore, tiny amounts of strontium, rubidium, molybdenum, chlorine, cadmium, and others elements were detected in KG. Several functionalities were qualitatively identified using Fourier Transform Infrared Spectroscopy. In the form of thin film, the absorption rate is low and the light transmittance exceeds 80%. The optical band gap was found to be around 4.15 eV. In regards of KG film dielectric properties, the capacitance frequency dependence exhibits conventional polar polymer dielectric behavior. At 1 kHz and room temperature, the estimated dielectric permittivity is between 6 and 10. These findings are intriguing, and they can be improved by combining different gum types for various applications in green opto-electronic systems. Highlights: A process was set up to deposit khaya gum films. Khaya film is found especially composed by copper, silicon and calcium oxides. A high optical band gap was deduced indicating high stability under illumination. Increasing temperature enhances conductivity and dielectric polarization. [ABSTRACT FROM AUTHOR]

Electronic devices with biomaterials have paved a way toward "green electronics" to create a sustainable future. Memristors are drawing growing attention with integrated sensing, memory, and computing for future artificial intelligence applications. Biomaterial is an emerging class of memristive materials (the device is called as biomemristor) for transient and/or biodegradable purpose. Importantly, several unique features such as faithful synaptic behaviors, bimodal switching, and biovoltage operations are observed in biomemristors. Moreover, the biomemristors are suitable for human‐related applications due to the inherent biocompatibility of biomaterials and flexibility of the device with ultrathin thickness. These features make the biomemristors promising for biorealistic neuromorphic applications. Herein, the state of the art of biomemristors are comprehensively summarized and systematically discussed with particular attention on their unique biorealistic features. Challenges and prospects toward the further development of biomemristors are also provided and discussed. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) are a new class of energy harvesting devices that have the potential to become a dominating technology for producing renewable energy. The versatility of their designs allows TENGs to harvest mechanical energy from sources like wind and water. Currently used renewable energy technologies have a restricted number of materials from which they can be constructed, such as metals, plastics, semiconductors, and rare‐earth metals. These materials are all non‐renewable in themselves as they require mining/drilling and are difficult to recycle at end of life. TENGs on the other hand can be built from a large repertoire of materials, including materials from bio‐based sources. Here, a TENG constructed fully from wood‐derived materials like lignin, cellulose, paper, and cardboard, thus making it 100% green, recyclable, and even biodegradable, is demonstrated. The device can produce a maximum voltage, current, and power of 232 V, 17 mA m–2, and 1.6 W m–2, respectively, which is enough to power electronic systems and charge 6.5 µF capacitors. Finally, the device is used in a smart package application as a self‐powered impact sensor. The work shows the feasibility of producing renewable energy technologies that are sustainable both with respect to their energy sources and their material composition. [ABSTRACT FROM AUTHOR]

TEMPO‐oxidized nanofibrillated cellulose (ONFC) with charged carboxyl groups is introduced for the efficient exfoliation of two‐dimensional (2D) MoS2/graphene composites. As an effective dispersant agent, ONFC can be easily absorbed between the adjacent layers, so as to prevent the accumulation of the exfoliated nanosheets. With the assistance of charged ONFC, the exfoliated MoS2/graphene is gradually increased in the aqueous dispersions with the elongated sonication time. After dewatering, self‐standing MoS2/Graphene/ONFC/CNTs composite films are rationally constructed using ONFC as flexible fibrous skeleton, and CNTs/graphene as 1D/2D interpenetrating electrical networks. Ultrathin MoS2 nanosheets anchored on the 1D/2D heterogeneous networks is directly acted as an ideal paper‐anode for lithium‐ion batteries (LIBs) without using traditional metallic current collector. The self‐standing flexible electrode materials based on natural cellulose will promote the future green electronics with high flexibility, miniaturization, and increased portability. [ABSTRACT FROM AUTHOR]

Edible electronics will facilitate point‐of‐care testing through safe devices digested/degraded in the body/environment after performing a specific function. This technology, to thrive, requires a library of materials that are the basic building blocks for eatable platforms. Edible electrical conductors fabricated with green methods and at a large scale and composed of food derivatives, ingestible in large amounts without risk for human health are needed. Here, conductive pastes made with materials with a high tolerable upper intake limit (≥mg kg−1 body weight per day) are proposed. Conductive oleogel composites, made with biodegradable and food‐grade materials like natural waxes, oils, and activated carbon conductive fillers, are presented. The proposed pastes are compatible with manufacturing processes such as direct ink writing and thus are suitable for an industrial scale‐up. These conductors are built without using solvents and with tunable electromechanical features and adhesion depending on the composition. They have antibacterial and hydrophobic properties so that they can be used in contact with food preventing contamination and preserving its organoleptic properties. As a proof‐of‐principle application, the edible conductive pastes are demonstrated to be effective edible contacts for food impedance analysis, to be integrated, for example, in smart fruit labels for ripening monitoring. [ABSTRACT FROM AUTHOR]

The development of polymer‐based conductive inks has gained increasing interest in the areas of printed and molded electronics. Graphene‐based materials are explored in this scope, reduced graphene oxide (rGO) being among the most used conductive filler components of the inks. Herein, rGO is doped with nitrogen to obtain N‐rGO; the replacement of oxygen atoms by nitrogen ones increases the electrical conductivity of graphene. Polymer‐based conductive inks reinforced with graphene are developed based on polyvinylpyrrolidone (PVP) as polymer binder and dihydrolevoglucosenone (Cyrene) as solvent, leading thus to environmentally friendly conductive inks. Screen‐printable inks are optimized in terms of viscosity and adhesion properties, leading to printed films with sheet resistance close to Rs = 1 kΩ sq−1, the graphene:PVP inks being also biocompatible and nontoxic. [ABSTRACT FROM AUTHOR]

The article titled "Revolutionizing Papertronics: Advanced Green, Tunable, and Flexible Components and Circuits" introduces a groundbreaking framework for papertronics, which combines biodegradability with flexibility. The framework utilizes functional inks, paper's capillary action, and hydrophobic wax to control flow, allowing for the creation of tunable electronic components and the integration of electronic circuits within paper. This new approach redefines the construction, performance, and utility of paper-based electronics. The authors of the article are Zahra Rafiee, Anwar Elhadad, and Seokheun Choi. [Extracted from the article]

This article presents the realization of a bandpass filter on a flexible biopolymer substrate with a suitable fabrication process. We used copper adhesive tape and laser structuring to fabricate the filter based on a quasi‐lumped microstrip structure. The filter characteristics are a central frequency of 2.45 GHz, a bandwidth of 20%, and insertion loss of 1.2 dB. It is demonstrated that the filter's performance remains almost constant under different bending, folding, and rolling conditions. The results show that the proposed bio‐sourced polymer is a good candidate for flexible green electronics and wearable applications. [ABSTRACT FROM AUTHOR]

This paper reports an unconventional approach for the formation of self‐healable and recyclable anisotropic conductive films (ACFs) using soft composites of gelatin hydrogels and liquid metals (LMs). The capsules of LMs dispersed inside the gelatin matrix can present satisfactory anisotropic conductance for electrical connections of vertically aligned, fine electrodes at room temperature by applying compressive pressures. The minimization of the capsule size as well as the softness of these LM‐gelatin hybrid ACFs enables high‐resolution integrations of deformable electronic systems, which can increase the integrity of freeform devices. In addition, the good fluidity of LMs and strong hydrogen bonding in gelatin enable these ACFs to be self‐healable at ambient conditions and even recyclable with no significant degradations in either their original electrical or mechanical properties. The utilization of these ACFs to integrate multiple interconnections of micro‐light‐emitting diode arrays on a soft elastomeric substrate demonstrates a stretchable display with its reliable operations during mechanical deformations, suggesting a promising strategy for next‐generation freeform and eco‐friendly green electronics. [ABSTRACT FROM AUTHOR]

Regenerated cellulose (RC)-based materials, a major biomass resource, have been widely used in various applications, owing to their degradability, sustainability, and green nature. Here, we constructed silver nanowire (AgNW)-based conductive microelectrodes on various RC substrates. The AgNW patterns on glass substrates fabricated by polyethylene glycol photolithography were transferred onto the RC hydrogel surface by the coagulation and regeneration of the cellulose solution. The dried AgNW-patterned RC films exhibited a high optical transmittance of 79% at 550 nm, an excellent tensile strength of 210 MPa, and excellent sheet resistance of 1.03 Ω/sq. Moreover, they exhibited good adhesion stability and excellent bending durability, compared to AgNW-coated/patterned polyethylene terephthalate films. After 5000 bending and 30 peeling test cycles, no significant increase in the sheet resistance was observed in the AgNW-patterned RC films. The AgNW-patterned RC films were converted into the AgNW-patterned RC hydrogel films by a spontaneous swelling process in an aqueous solution. This conductive hydrogel film can be used as important components, such as the membrane and coating in bioelectronics interfaced with biological systems. We anticipate that this approach combined with conductive AgNW patterns and ecofriendly RC substrates can render these microelectrodes suitable candidates in the development of next-generation green electronics and high-performance bioelectronics. [ABSTRACT FROM AUTHOR]

Plastics are now causing challenging environmental issues, especially electronic waste (E‐waste) and microplastics. While no single solution exists to address all these complex problems, superworms' ingestion behavior toward plastics provides an innovative way to reduce plastic pollutions. Here, it is demonstrated that poly(3,4‐ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)/montmorillonite (MMT) composites are biodegradable with versatile multifunctionalities originating from natural nacre‐inspired layered nanostructures. While their physical performances are modulated interdependently, eco‐biodegradability of the MMT/PEDOT:PSS composites are confirmed by the superworm's ingestion behaviors and their chemical changes after digestion. The electrically conductive composites with PEDOT:PSS also exhibit excellent mechanical properties, thermal stability, flame retardancy, long‐term water stability, flexibility, and electrochemical properties. Combined with these inherent multifaceted properties, the eco‐biodegradable features of the MMT/PEDOT:PSS composites open a new direction to use electronic materials for emerging eco‐friendly applications, including green‐electronics, bioelectronics, and edible‐electronics. [ABSTRACT FROM AUTHOR]

Photonic and electronic devices currently face challenges in terms of improved efficiency of energy harvesting and light emission, renewable energy and materials, and the development of eco‐friendly materials. Owing to the emergence of world‐wide concerns about environmental degradation and the ensuing regulations, demand for environmentally friendly technology has been increasing in recent years. As the current technology of creating electronics and photonics devices based on semiconductors heavily relies on processes that produce a series of hazardous chemicals, development of renewable and eco‐friendly materials has become immensely important. Two of the most promising materials in this respect are silk and paper, and this progress report will investigate their unique properties for both photonic and electronic applications. These two natural materials have been intensively studied in the last decades and have shown promising aspects for use in future green technologies. [ABSTRACT FROM AUTHOR]

Biodegradable or eco‐degradable electronics is an emerging field of technology capable of reducing the excessively increasing electronic waste originating from the rapid development of personalized and bio‐integrated devices and skin adhesive patches. Through an advantageous solution process, biodegradable conductive pastes can be employed in various applications of soft and flexible devices. Herein a biodegradable conductive paste composed of molybdenum (Mo) microparticles and polybutylene adipate terephthalate (PBAT) exhibiting excellent mechanical flexibility and stretchability is reported, while also demonstrating substantially superior mechanical and conductive properties compared with previously reported biodegradable polymer matrices such as poly butanedithiol 1,3,5‐triallyl‐1,3,5‐triazine‐2,4,6‐(1H,3H,5H)‐trione pentenoic anhydride (PBTPA) and Candelilla wax (CW) owing to the significant elongation of PBAT. Moderate dissolution in phosphate buffer saline (PBS) accomplishes its full biodegradability and programmable lifecycle. Tetraglycol (TG) enhances elongation and conductivity performance by acting as a lubricant and improving the dispersion of microparticles. The practical implications of the Mo/PBAT pastes are demonstrated in numerous biodegradable electronic applications such as electrodes, strain and temperature sensors, joule heaters, interconnectors, and freestanding radiofrequency (RF) coils. [ABSTRACT FROM AUTHOR]

Eco‐friendliness is becoming an indispensable feature for electrical and electronic equipment to thrive in the competitive market. This comprehensive review is the first to define eco‐friendly electronics in its multiple meanings: power saving devices, end‐of‐life impact attenuators, equipment whose manufacturing uses green processing, electronics that use materials that minimize environmental and health risks, designs that improve lifespan, reparability, etc. More specifically, this review discusses eco‐friendly technologies and materials that are being introduced to replace the well‐established ones. This is done for all material classes (metals, polymers, ceramics, and composites). Manufacturing, recycling, and final product characteristics are discussed in their various interconnected aspects. Additionally, the concept of consciously planned obsolescence is introduced to address the paradoxical relationship between durability and efficiency. The overall conclusions are that there is an important global trend to make electronics more eco‐friendly. However, matching the performance and stability of well‐established materials and technologies seems to be the main barrier to achieve it. These new implementations can have detrimental or beneficial net impacts on the environment. Assessing their net outcome is challenging because their impacts are frequently unknown and the current evaluation methods (and tools) are incapable of comprehensively quantifying these impacts and generating reliable verdicts. [ABSTRACT FROM AUTHOR]

Plastic‐based electronics fill the gaps in conventional rigid silicon‐based devices toward the applications in soft interfaces. However, people in the future should also consider their potential environmental impact if tons of non‐degradable plastics are applied. Silk fibroin is a superior substrate alternative for the development of "green" electronics; whereas, the brittleness of silk films is still a major limitation impeding their practical use. Different from the widely reported polyphasic composite approaches, here a trace‐ion‐assisted plasticization strategy is developed, and shape‐engineerable pure silk fibroin paper (PSFP) is prepared for the first time, which can be engraved and crumpled like a sheet of paper in the dry state. The PSFPs exhibit higher tensile fracture energy (14.4 ± 4 kJ m−2) than any typical plastic‐electronic‐substrates as far as it is known. The intrinsic brittleness of pure silk films is overcome, and the PSFP can be easily engineered to form periodic meshes, electronic prototypes, and kirigami‐based devices, which are beyond the reported regenerated silk films or silk composite films. Moreover, the scrape coating method employed here is simple, highly repeatable, and suitable for scaled production of low‐cost PSFP continuously. Collectively, the PSFP is generalizable to various shapes and devices, represents an ideal substrate alternative to plastic electronics. [ABSTRACT FROM AUTHOR]

The growing demand of disposable electronics raises serious concerns for the corresponding increase in the amount of electronic waste, with severe environmental impact. Organic and flexible electronics have been proposed long ago as a more sustainable and energy-efficient technological platform with respect to established ones. Yet, such technology is leading to a drastic increase of plastic waste if common approaches for flexible substrates are followed. In this scenario, biodegradable solutions can significantly limit the environmental impact, actively contributing to eliminate the waste streams (plastic or electronic) associated with disposal of devices. However, achieving suitably scalable processes to pattern mechanically robust organic electronics onto largely available biodegradable substrates is still an open challenge. In this work, all-organic and highly flexible field-effect transistors, inkjet printed onto the biodegradable and compostable commercial substrate Mater-Bi, are demonstrated. Because of the thermal instability of Mater-Bi, no annealing steps are applied, producing devices with limited carrier mobility, yet showing correct n-type behavior and robustness to bending and crumpling. The degradation behavior of the final system shows unaltered biodegradability level according to ISO 14851. These results represent a promising step toward sustainable flexible and large-area electronics, combining energy and materials efficient processes with largely available biodegradable substrates. [ABSTRACT FROM AUTHOR]

The paper presents a Scientometric analysis of publications of green electronics at global level during 1989 to 2014 as reflected web of science database. The study covers 7142 publications during the period. The study focused on author productivity, most used journals, sources, country, language etc.. It is found from the analysis that 92.31% of the articles were produced by multiple authors. It is found that the multi-author distribution is the most elevated contrast with single-author distribution. "Cederbaum LS" published highest number of articles for the study period. 91 percent of collaboration authors articles published during the study periods. Chinese Academy of Sciences had contributed the highest number of research publications. The USA country has the highest productivity and highest local and global citation scores measured. Physical Review B has emerged as the most preferred journal by authors for publication. [ABSTRACT FROM AUTHOR]

Here we report broad range, tunable and foldable paper-based passive components and filter circuits. Reported electronics fabricated through solvent-free garage fabrication techniques using inexpensive and off-the-shelf materials like graphite pencils, aluminum foil, copper tape, paper, and such Previously reported paper-based passive electronic circuits are single-valued and lack real-time tunability. Broad range passive components and tunable RC filter circuits fabricated through inexpensive, eco-friendly, and cleanroom-free fabrication techniques like hand drawing of graphite pencils on paper and garage fabrication techniques like cutting-pasting of readily available materials demonstrated expected functionalities with tunable cut-off frequencies. Cut-off frequencies of low and high pass filters are tunned from 15 to 190 kHz by penciling graphite flakes of different graphite content pencils. The paper-based passive electronic circuits showed robust performance against applied stress during bending and folding. To the best of our knowledge, no studies have been reported on tunable paper-based passive electronic circuits. These paper-based electronic components and circuits open pathways for green and foldable power electronics, flexible and foldable printed circuit boards and consumer electronics, touchpads, disposable security systems, soft robotics, and many more. [ABSTRACT FROM AUTHOR]

As the cost of electronics decreases, the demand for short‐term and single‐use applications, such as smart packaging, increases. Consequently, there is significant need for electronically active biodegradable materials to reduce the environmental impact of disposable electronic devices. A bilayer dielectric is developed based on environmentally friendly, low‐cost solution‐processable polymers, fabricated by thermally crosslinking a toluene diisocyanate‐terminated polycaprolactone (TPCL) layer with the hydroxyl groups of a poly(vinyl alcohol)/cellulose nanocrystal (CNC) blended dielectric (PVAC). Metal–insulator–metal (MIM) capacitors are fabricated and characterized under ambient and humid conditions. The incorporation of a TPCL layer in the bilayer dielectric results in a large reduction in moisture sensitivity when compared to neat PVAC without significantly altering the dielectric constant. When utilized as a dielectric in organic thin‐film transistors (OTFTs), the transistors prepared with the PVAC/TPCL dielectric have greater on/off ratios and hole mobilities, with reduced hysteresis compared to devices fabricated with PVAC. Furthermore, the fabricated OTFTs function at operating voltages six times lower when compared against a traditional silicon dioxide (SiO2) dielectric. The facile processing, combined with superior device performance, makes this green bilayer dielectric a promising candidate material for biodegradable disposable electronic applications. [ABSTRACT FROM AUTHOR]

Developing new energy technology is a significant challenge in the context of the energy crisis. As a novel energy conversion device to convert mechanical energy into electricity, the triboelectric nanogenerator (TENG) has attracted significant attention in the past few years. The choice of component materials directly affects the cost, environmental performance, output performance, and preparation process of a TENG. In recent years, cellulose paper has become an ideal material for fabricating a TENG due to its lightweight, biodegradability, low‐cost, high flexibility, environmental friendliness, porosity, and easy modification. Cellulose paper‐based TENG has become a hot topic in the field of green energy. This paper systematically summarizes the research progress of the cellulose paper‐based TENG. The advantages of cellulose paper as raw material to fabricate a TENG, followed by introducing the different roles of cellulose paper in paper‐based TENGs, are first discussed. Then the recent progress in energy storage, performance optimization methods, hybridization, and applications of cellulose paper‐based TENGs is successively elaborated. Finally, some perspectives and challenges for the future development of cellulose paper‐based TENG are discussed to provide guidance. [ABSTRACT FROM AUTHOR]

The development of green materials is an important part of corporate social responsibility. Companies need to use resources legitimately and have environmental protection responsibility. Forecasting the growth trend of green copper clad laminate (CCL) material is crucial for manufacturers of printed circuit boards and green CCLs. Early and accurate understanding of such trends in this industry can lead to the early acquisition of opportunities for related markets and technological development. Because historical data samples associated with green CCL are small and typically lack a normal distribution, employing conventional regression analysis or time series models for forecasting is not suitable for testing-related presumptions. To address this issue, this study adopts grey system theory (GST) and a fuzzy time series (FTS) model as forecasting methods. The results show that effective forecasting can be achieved by applying either a GM (1,1) α model or heuristic FTS model to the data of a small and non-normally distributed sample. [ABSTRACT FROM AUTHOR]

Natural biomaterials are potential candidates for the next generation of green electronics due to their biocompatibility and biodegradability. On the other hand, the application of biocomposite systems in information storage, photoelectrochemical sensing, and biomedicine has further promoted the progress of environmentally benign bioelectronics. Here, we mainly review recent progress in the development of biocomposites in data storage, focusing on the application of biocomposites in resistive random-access memory (RRAM) and field effect transistors (FET) with their device structure, working mechanism, flexibility, transient characteristics. Specifically, we discuss the application of biocomposite-based non-volatile memories for simulating biological synapse. Finally, the application prospect and development potential of biocomposites are presented. [ABSTRACT FROM AUTHOR]

This letter describes a single-transistor oscillator implemented on a paper substrate at the operating frequency of 24 GHz, based on a design procedure that makes it possible to overcome the limitations caused by thin high-loss substrates and package parasitics of commercial components. The commercial transistor adopted in the oscillator is led to instability by exploiting its parasitic gate inductance. The drain network compensates for the parasitic inductance of the transistor package and connects the oscillator circuit to a 50- $\Omega $ load resistance. Finally, an external inductor at the source terminal is used to resonate out the capacitive contribution of the circuit at the oscillation frequency. Overall, the active device appears in a quasi-common-drain stage. Experimental results on prototype show that the oscillator exhibits an output power of +6.2 dBm at 24 GHz, with a dc power consumption of 72.5 mW. [ABSTRACT FROM AUTHOR]

The rapid growth and adoption of microelectronics around the world has resulted in an increased awareness of potential environmental issues related to their use and disposal. Halogens, which have had various uses in microelectronics over the years, are known to emit toxic and corrosive gases during the disposal of electronic waste. Many organizations have applied pressure to the electronics industry to eliminate halogens completely (e.g., fluorine, chlorine, and bromine) from their products. Among the various efforts toward environmentally friendly products, making electronics completely halogen-free has gained significant attention, particularly in Asia and Europe. This initiative even impacts conformal coatings worldwide, on which most electronics rely for their long-term protection, reliability, and high performance against water and other corrosive harsh environments. Among the various coating options, the parylene family of conformal coatings offers beneficial properties to the microelectronics, improved over many properties offered by common epoxies, acrylics, urethanes, and silicones. Although parylene N is the only commercially available parylene that does not contain any halogens, its barrier performance against moisture and other corrosive chemicals is not quite as robust as the other parylenes. To meet the industry's current and future requirements, a new halogen-free parylene, ParyFree®, has been developed. This study introduces a new parylene type to the microelectronics industry and shares the characterization and qualification results of ParyFree® parylene conformal coating for the protection, reliability, and robust performance of microelectronics. Testing on the new coating includes IPX water resistance, corrosion resistance, and qualification per IPC-CC-830B. [ABSTRACT FROM AUTHOR]

In this paper, a water based All Dielectric Frequency Selective Surface (ADFSS) is presented made of renewable materials. This surface is based on a modified dielectric resonator incorporating air holes inside the water to increase its Q factor. The ADFSS shows a low pass response with a cutoff frequency of 3.7 GHz. The surface is simulated and measured giving reasonable results. [ABSTRACT FROM AUTHOR]