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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]

Exploitation of low‐dimensional metal‐oxide semiconductor nanowires (MOS NWs) with peculiar and radial coaxial architectures is of great significance for constructing nanoscale, high‐performance, multi‐module integrable functional electronic products. Here, highly ordered In2O3@ZnO coaxial NW arrays (CNWA) using a simple and economical electrospinning technique are synthesized and assembled into field‐effect transistors (FETs). Featuring strong carrier effusion efficiency at the In2O3@ZnO circular heterogeneous interface, the field effect mobility (εFE) gets an intrinsic improvement and can reach as high as 202.3 cm2 V‒1 s‒1 for high‐k‐based CNWA FETs, which exceeds the performance of oxide‐based FETs devices reported by far. Furthermore, the unique structural advantages endowing In2O3@ZnO CNWA FETs with excellent optoelectronic coupling capabilities are identified, for which further optoelectronic detection and artificial photonic synaptic devices are constructed and functional simulations are implemented. This work offers new insights in designing optoelectronics and artificial synapses to process and recognize information for neuromorphic computing and artificial intelligence applications. [ABSTRACT FROM AUTHOR]

Metal oxide field‐effect transistors (MOFETs) represent a promising technology for applications in existing but alsoemerging large‐area electronics. Simultaneously, the rise of 1D nanomaterials with unique properties, represented by nanofibers (NFs), has also energized research. Thus, developing 1D nanofiber networks (NFNs) to act as the potential building blocks for use in fundamental elements of transistors is considered to be a promising approach torealize high‐performance 1D electronics. However, high processing temperatures and disordered nanofiber distribution represent two remaining technical challenges. Here, electrospun highly aligned IGZO (a‐IGZO) nanofiber arrays with low‐thermal‐budget of 350 °C and impressive device characteristics are achieved, including a μFE of 5.63 cm2 V–1 s–1 and superior on/off current ratio of ≈107. When ALD‐derived high‐k HfAlOx thin films are employed as gate dielectrics, the source/drain voltage (VDS) can be substantially reduced by ten times to a range of only 03 V, along with a three times improvement in mobility to a respectable value of 15.9 cm2 V–1 s–1. Successful integrations of logic operation, sensor, and flexible devices implies the potential prospect of a‐IGZO NFN FETs in multifunctional electronics. The strategy for combining cryogenic processes and parallel arrays provides a feasible and reliable route in building future low‐power, high‐performance flexible electronics. [ABSTRACT FROM AUTHOR]

Electrochromic devices (ECDs) comprising visible/near‐infrared (NIR) transparent amorphous indium zinc oxide (a‐IZO) outermost layers and novel NIR‐emitting electrolytes are proposed for smart windows of buildings in cold climate regions. The electrolytes are composed of a di‐urethane cross‐linked poly(oxyethylene)(POE)/siloxane hybrid matrix (d‐Ut(600), 600 is the average molecular weight of the POE chains in gmol−1), 1‐butyl‐3‐methylimidazolium chloride ionic liquid, and the Er(tta)3(H2O)2 complex (tta− is 2‐thenoyltrifluoracetonate). The electrolytes, synthesized by sol‐gel route, were obtained as transparent, flexible, and hydrophilic monoliths with nanoscale surface roughness, exhibiting emission in the NIR wavelength region. The first electro‐optical tests, performed in 2019, with an archetypal ECD including amorphous tungsten oxide and crystalline nickel oxide as EC layers, a‐IZO as outermost layers, and d‐Ut(600)400Er(tta)3(H2O)2[Bmim]Cl (400 is the molar ratio of oxyethylene units/Er3+ ion) as the electrolyte, demonstrated rather low coloration efficiency (CEin/CEout) values of −4/+6 cm2 C−1 at 555 nm. After 3 years of storage at rest in the dark and at room temperature, the same device demonstrates a huge performance enhancement, leading to CEin/CEout values about two orders of magnitude higher, apart from higher optical density, and improved cycling stability. In addition, this device offers a bright hot, and semi‐bright warm dual modulation operation suitable for smart windows of skylights, roof lights, upper windows, inclined glazing, and privacy glazing of buildings located in cold climate regions. [ABSTRACT FROM AUTHOR]

Advanced light management via front‐coated photonic nanostructures is a promising strategy to enhance photovoltaic (PV) efficiency through wave‐optical light‐trapping (LT) effects, avoiding the conventional texturing processes that induce the degradation of electrical performance due to increased carrier recombination. Titanium dioxide (TiO2) honeycomb arrays with different geometry are engineered through a highly‐scalable colloidal lithography method on flat crystalline silicon (c‐Si) wafers and tested on standard planar c‐Si interdigitated back‐contact solar cells (pIBCSCs). The photonic‐structured wafers achieve an optical photocurrent of 36.6 mA cm−2, mainly due to a broad anti‐reflection effect from the 693 nm thick nanostructured coatings. In contrast, the pIBCSC test devices reach 14% efficiency with 679 nm thick TiO2 nanostructures, corresponding to a ≈30% efficiency gain relative to uncoated pIBCSCs. In addition, several designed structures show unmatched angular acceptance enhancements in efficiency (up to 63% gain) and photocurrent density (up to 68% gain). The high‐performing (yet electrically harmless) LT scheme, here presented, entails an up‐and‐coming alternative to conventional texturing for c‐Si technological improvement that can be straightforwardly integrated into the established PV industry. [ABSTRACT FROM AUTHOR]

Although In2O3 nanofibers (NFs) are regarded as one of the active channel materials for next‐generation, low‐cost thin‐film transistors (TFTs), these NFs‐based devices still suffer from the degraded carrier mobility and operational instability, limiting the ability of such devices to replace current polycrystalline silicon technologies. Here, it is shown that nanofiber channel transistors with high electron mobility and operational stability can be achieved by selectively doping Zn element into electrospun In2O3 NFs. By precisely manipulating the doping level during NFs fabrication, their crystallinity, surface morphology, and corresponding device performance can be regulated reliably for enhanced transistor performances. It has been detected that InZnO/SiO2 TFTs with an optimized Zn doping concentration of 50% have demonstrated the high field‐effect mobility (µFE) of 6.38 cm2 V−1 s−1, the larger ION/IOFF of 4.12 × 107 and operation in the energy‐efficient enhancement‐mode. Low frequency noise (LFN) measurements have displayed that the scattering and defects inside the NFs are effectively suppressed by the particular microstructure. When integrating ALD‐derived Al2O3 films as the gate dielectric into TFTs devices, their electron mobility and ION/IOFF can be further improved to 37.82 cm2 V−1 s−1 and 2.92 × 108, respectively. To demonstrate the potential toward more complex logic applications, a low voltage resistor‐loaded unipolar inverter is built by using InZnO/Al2O3 TFT, exhibiting a high gain of 20.95 and full swing characteristics. These optimized parameters have demonstrated the significant advance of this electrospinning technique toward practical applications for high performance and large‐scale electronics. [ABSTRACT FROM AUTHOR]

Background: Diabetes is a heterogeneous and multifactorial disease. However, glycemia and glycated hemoglobin have been the focus of diabetes diagnosis and management for the last decades. As diabetes management goes far beyond glucose control, it has become clear that assessment of other biochemical parameters gives a much wider view of the metabolic state of each individual, enabling a precision medicine approach. Methods: In this review, we summarize and discuss indexes that have been used in epidemiological studies and in the clinical practice. Results: Indexes of insulin secretion, sensitivity/resistance and metabolism have been developed and validated over the years to account also with insulin, C‐peptide, triglycerides or even anthropometric measures. Nevertheless, each one has their own objective and consequently, advantages and disadvantages for specific cases. Thus, we discuss how new technologies, namely new sensors but also new softwares/applications, can improve the diagnosis and management of diabetes, both for healthcare professionals but also for caretakers and, importantly, to promote the empowerment of people living with diabetes. Conclusions: In long‐term, the solution for a better diabetes management would be a platform that allows to integrate all sorts of relevant information for the person with diabetes and for the healthcare practitioners, namely glucose, insulin and C‐peptide or, in case of need, other parameters/indexes at home, sometimes more than once a day. This solution would allow a better and simpler disease management, more adequate therapeutics thereby improving patients' quality of life and reducing associated costs. [ABSTRACT FROM AUTHOR]

Thin‐film transistors based on metal oxide semiconductors have become a mainstream technology for application in driving low‐cost backplanes of active matrix liquid crystal displays. Although significant progress has been made in traditional marketable devices based on physical vapor deposition derived metal oxides, it has still been hindered by low yield and poor compatibility. Fortunately, developing solution‐based 1D nanofiber networks to act as the fundamental building blocks for transistor has proven to be a simpler, higher‐throughput approach. However, oxide transistors based on such princesses suffer from degraded carrier mobility and operational instability, preventing the ability of such devices from replacing present polycrystalline Si technologies. Herein, it is shown that double channel heterojunction transistors with high electron mobility (>40 cm2 V−1 s−1) and operational stability can be achieved from electrospun double channels composed of In2O3 and ZnO layers. Adjusting the stacking order and the stacking density of In2O3 and ZnO layers can effectively optimize the interface electron trap, leading to the formation of 2D electron gas and the reduction of stress‐induced instability. These findings further elucidate the significant advance of electrospinning‐derived double channel heterojunction transistors toward practical applications for future low‐cost and high‐performance electronics. [ABSTRACT FROM AUTHOR]

Memristor crossbar arrays can compose the efficient hardware for artificial intelligent applications. However, the requirements for a linear and symmetric synaptic weight update and low cycle‐to‐cycle (C2C) and device‐to‐device variability as well as the sneak‐path current issue have been delaying its further development. This study reports on a thin‐film amorphous oxide‐based 4×4 1‐transistor 1‐memristor (1T1M) crossbar. The a‐IGZO crossbar is built on a flexible polyimide substrate, enabling IoT and wearable applications. In the novel framework, the thin‐film transistor and memristor are fabricated at the same level, with the same processing steps and sharing the same materials for all layers. The 1T1M cells show linear and symmetrical plasticity characteristic with low C2C variability. The memristor performs like an analog dot product engine and vector–matrix multiplications in the 4×4 crossbars is demonstrated experimentally, in which the sneak‐path current issue is successfully suppressed, resulting in a proof‐of‐concept for a cost‐effective, flexible artificial neural networks hardware. [ABSTRACT FROM AUTHOR]

An increase in the demand for the next generation of "Internet‐of‐Things" (IoT) has motivated efforts to develop flexible and affordable smart electronic systems, in line with sustainable development and carbon neutrality. Cellulose holds the potential to fulfil such demands as a low‐cost green material due to its abundant and renewable nature and tunable properties. Here, a cellulose‐based ionic conductive substrate compatible with printing techniques that combines the mechanical robustness, thermal resistance and surface smoothness of cellulose nanofibrils nanopaper with the high capacitance of a regenerated cellulose hydrogel electrolyte, is reported. Fully screen‐printed electrolyte‐gated transistors and universal logic gates are demonstrated using the engineered ionic conductive nanopaper and zinc oxide nanoplates as the semiconductor layer. The devices exhibit low‐voltage operation (<3 V), and remarkable mechanical endurance under outward folding due to the combination of the robustness of the nanopaper and the compliance of the semiconductor layer provided by the ZnO nanoplates. The printed devices and the ion‐conductive nanopaper can be efficiently recycled to fabricate new devices, which is compatible with the circular economy concept. [ABSTRACT FROM AUTHOR]

Laser‐induced graphene (LIG) produced by irradiation of paper (paper‐LIG)holds substantial promise for flexible devices. This article presents paper‐LIG humidity and temperature sensors fabricated by single‐step irradiation of common filter paper with a pulsed UV laser (355 nm). The influence of the process parameters on the conversion of cellulose fibers into LIG is discussed based on the resulting morphology, structure, conductivity, and chemical composition, revealing a distinct barrier to transformation and a propagation behavior not seen under CO2 laser irradiation. The obtained material is constituted by a porous, electrically conductive network of fibers. The paper‐LIG relative humidity (RH) and temperature sensors with sensitivities of up to 1.3 × 10−3%RH−1 and ‐ 2.8 × 10−3 °C−1, respectively, are examined in terms of their linearity, reproducibility, and response time. A detailed discussion on the response mechanism is presented in the context of literature, pointing towards the absorption of water molecules in the interlayer spacing of graphene as the main reason for the increase in resistance with RH. Additionally, a contribution from variable range hopping along the ab plane of graphene at high RH is suggested. These results demonstrate the potential of paper‐LIG for low‐cost, sustainable, and environmentally friendly sensing. [ABSTRACT FROM AUTHOR]

Printed electronics answers to the emerging trend of using truly inexpensive and easily accessible techniques to design and fabricate low‐cost and recyclable flexible electronic components. Nevertheless, printing of inorganic semiconductor materials arises some barriers for flexible electronics, as they usually may require high annealing temperatures to enhance their electronic performances, which are not compatible with paper. Here, the formulation of a water‐based, screen‐printable ink loaded with zinc oxide nanoparticles that does not require any sintering process is reported. The ink is used to create the channel in fully printed electrolyte‐gated transistors on paper, gated by a cellulose‐based ionic conductive sticker. The high conformability of the electrolyte‐sticker mitigates the effect of the surface roughness of the channel, yielding transistors that operate under low voltage (<2.5 V) with a current modulation above 104 and μSat ≈ 22 cm2 V−1 s−1. These devices operate even under moderate outward bending conditions. The screen‐printed transistors are readily integrated in "universal" logic gates (NOR and NAND) by using ubiquitous calligraphy accessories for patterning of conductive paths and graphitic load resistances. This demonstrates the manufacturing of reliable and recyclable cellulose‐based iontronic circuits with low power consumption, paving the way to a new era of sustainable "green" electronics. [ABSTRACT FROM AUTHOR]

Laser irradiation to induce networks of graphene-based structures toward cost-effective, flexible device fabrication is a highly pursued area, with applications in various polymeric substrates. This work reports the application of this approach toward commonly available, eco-friendly, low-cost substrates, namely, chromatographic and office papers. Through an appropriate chemical treatment with sodium tetraborate as a fire-retardant agent, photothermal conversion to porous laser-induced graphene (LIG) on paper is achieved. Raman peaks are identified, with I2D/IG and ID/IG peak ratios of 0.616 ± 0.095 and 1.281 ± 0.173, showing the formation of multilayered graphenic material, exhibiting sheet resistances as low as 56.0 Ω sq-1. Coplanar, LIG-based, three-electrode systems (working, counter and reference electrodes) are produced and characterized, showing high current Faradaic oxidation and reduction peaks, translating in high electrochemical active area, doubling the geometric area. Good electron transfer kinetics performed exclusively with on-chip measurements are reached, with k0 values as high as 7.15 x 10-4 cm s-1. Proof-of-concept, amperometric, enzymatic glucose biosensors are developed, exhibiting good analytical performance in physiologically relevant glucose levels, with results pointing to the applicability of paper-based LIG toward efficient, disposable electrochemical sensor development, increasing their sustainability and accessibility, while simplifying their production and reducing their cost. [ABSTRACT FROM AUTHOR]

Electronic‐skin (e‐skin) is pursued, as of the 21st century, to mimic the sensory capabilities of human skin for several applications. Pressure is one of the key stimuli in e‐skin technology, frequently detected using piezoresistive sensors, which consist of film layers commonly micro‐structured to improve their performance, either through expensive photolithography techniques or other poorly customizable approaches. The authors' group recently introduced laser engraving as a low‐cost yet highly customizable micro‐structuring technique to produce molds, despite the limited resolution. Combining laser engraving with shrinking polymeric films (SPFs) to fabricate molds is an innovative strategy to greatly improve the performance of the sensors, allowing for thinner and highly conformal sensor layers while minimizing costs. Shrinking these SPFs after their engraving yields smaller yet high aspect ratio cavities. Herein, all the laser engraving parameters are thoroughly investigated to optimize SPF molds (arrays of 10 µm vertical lines spaced by 200 µm, engraved with 3% laser power, 25% speed, and 0.04'' between laser and substrate) to produce e‐skin piezoresistive sensors with a sensitivity of −1.4 kPa−1 below 10 kPa, a 1.4 ms recovery time, and a capability to detect distinct body movements, illustrating the great potential for health monitoring applications. [ABSTRACT FROM AUTHOR]

Tungsten oxide (WO3) nanostructured films are synthesized under microwave radiation with synthesis times of 5 and 10 min, at 150 or 180 °C. This ultrafast synthesis route results in uniform and well‐crystallized WO3 nanostructured films fully covering the substrates. A plate‐like hierarchical structure is observed at 150 °C, and closely packed rectangular nanorods are formed at 180 °C. For both temperatures, the nanostructures self‐organize into larger flower‐like structures. The increase of the synthesis time from 5 to 10 min at 180 °C results in thicker films, reaching ≈4 μm. X‐ray diffraction (XRD) and Raman spectroscopy reveal that the films grow with the WO3 orthorhombic crystalline phase (o‐WO3·0.33H2O). Photoluminescence (PL) measurements are performed for all the films, and their optical bandgaps are estimated through diffuse reflectance spectroscopy. The WO3 films have their photocatalytic activity assessed from rhodamine B (RhB) degradation under solar radiation. The Mott–Schottky plots confirm the n‐type character of the films with the flat‐band potentials and electron concentrations being estimated for the best photocatalysts. This study associates the eco‐friendly, fast, and low‐cost aspects of the synthesis route to the production of highly photoactive materials, which can effectively contribute to environmental remediation. [ABSTRACT FROM AUTHOR]

The world in the 21st century is confronted with multifaceted challenges against rapid climate change and continuous ecological disturbances caused by revolutionary socio‐economic developments, accelerated expansion of disposable electronic gadgets, and growing dependence on unrecyclable raw materials, among others. The ever‐increasing consumer demand for electronic devices is significantly contributing to the world's fastest‐growing waste stream, known as electronic waste (e‐waste), which is becoming an environmental threat at an alarming rate due to its toxic legacy. The ever‐shortening lifespan of smart technologies has created a "tsunami of e‐waste," as the United Nations has characterized it, with 50 million tons accumulated each year, of which only 20% undergo formal e‐recycling. Therefore, the challenge of optimizing the current resources management models with an aim of improving the manufacturing processes and lifecycles of electronic devices, as well as building a circular economy, has become significantly prominent. Paper/cellulose, which covers a wide range of essential needs in everyday scenarios (from packaging to writing utilities), constitutes promising candidates for the effective achievement of a circular economy. Particularly, cellulose is revealed as an advantageous material for electronic applications because of its abundant availability, which contributes to its cost‐effectiveness, straightforward fabrication process, and high recyclability and reproducibility. [ABSTRACT FROM AUTHOR]

It has been long recognized that solid polymer electrolytes (SPEs) are potentially interesting for solid‐state electrochemical devices. Gellan gum (Ge)‐based SPEs, plasticized with glycerol (Gly) and doped with lithium bis(trifluoromethanesulfone)imide (LiTFSI) were prepared by the solvent casting technique, and their properties were evaluated. LiTFSI‐based SPE systems exhibit, on the average, higher conductivities than similar systems with other lithium salts. The structure, morphology, complex impedance spectroscopy, cyclic voltammetry and thermal stability of the new electrolyte system were characterized. Electrochromic devices (ECDs) were built with optimized electrolyte samples and their performance was analyzed. The samples were applied in small ECDs with glass/ITO/CeO2‐TiO2/SPE/Prussian blue/ITO/glass configuration. The devices presented a two‐modulation operation: a semi‐bright mode (−2.5 V) and a dark mode (+0.5 V). The best results were obtained with the ECD containing the GeGly1Li2.4 electrolyte, for which the transmittance (T) values in the bleached and colored states were ca. 33.4/43.0 % and 5.4/8.8 % at 555/1000 nm, respectively. These results correspond to ΔT and ΔOD values of 28.0/34.2 % and 0.79/0.69, respectively, which give quite high CEin and CEout values of −4925 cm2 C−1 for bleaching (Qin=−272.1 μC cm−2), and 2062 cm2 C−1 for coloring (Qout=650.0 μC cm−2), at 630 nm. This electro‐optical performance suggests that the proposed SPE systems are promising materials to be further investigated and applied in ECDs. [ABSTRACT FROM AUTHOR]

The study shows the incorporation of chiral nematic photonic cellulose nanocrystal (CNC) films, well known for their adaptive character of selective reflection of circular polarized light (CPL), and silicon‐based thin‐film photodiodes, thus achieving a light sensor capable of discriminating right‐ from left‐handed CPL. The circular polarization (CP) response is maximum for specific wavelengths in the green‐to‐red region. When subjected to these wavelengths, they produce photocurrents that are over 50% distinct between the two CP states. Proper signal processing, thus, yields a binary output depending on the handedness of the light. Through the addition of monovalent salt to the initial CNC suspension, a blueshift to the photonic band gap is induced, enabling a larger wavelength gamut and application possibilities. The measured results are then used as a basis for electromagnetic simulations that show remarkable consistency with the experimental results, thus defining a new tool that can be used to efficiently optimize the devices' response. Fast transient responses to CPL are shown with possible logic operations, as well as humidity sensing. The developed devices are, thus, applicable in areas as diverse as imaging, CPL sensing, optoelectronic counterfeiting, and information processing with logic states that depend solely on the handedness of the incident light. [ABSTRACT FROM AUTHOR]

Novel nature‐based engineered functional materials combined with sustainable and economically efficient processes are among the great challenges for the future of mankind. In this context, this work presents a new generation of versatile flexible and highly conformable regenerated cellulose hydrogel electrolytes with high ionic conductivity and self‐healing ability, capable of being (re)used in electrical and electrochemical devices. They can be provided in the form of stickers and easily applied as gate dielectric onto flexible indium–gallium–zinc oxide transistors, decreasing the manufacturing complexity. Flexible and low‐voltage (<2.5 V) circuits can be handwritten on‐demand on paper transistors for patterning of conductive/resistive lines. This user‐friendly and simplified manufacturing approach holds potential for fast production of low‐cost, portable, disposable/recyclable, and low‐power ion‐controlled electronics on paper, making it attractive for application in sensors and concepts such as the "Internet‐on‐Things." [ABSTRACT FROM AUTHOR]

Monitorization of gait‐related parameters is of the utmost importance to prevent complications in several diseases, ensuring affordable healthcare for the growing amount of chronic, lifestyle‐related diseases and also for improving motion performance. Sensorized insoles allow to both pressure data and gait timings to be extracted non‐intrusively in a point of care paradigm. Laser‐induced graphene (LIG) offers a path to the integration of sensors in different kinds of materials, including cork, a common insole material. In this work, piezoresistive sensors are developed by providing conductivity to natural cork and agglomerate cork through the direct synthesis of LIG by UV irradiation. Highly isotropic conductive LIG regions with less than 100 Ω sq−1 are patterned and their piezoresistive response for up to 1132 kPa is assessed with sensitivities up to 0.02 kPa−1. A low‐cost prototype insole is devised and tested, proving the potential of this kind of functional cork as a green alternative for gait analysis platforms. [ABSTRACT FROM AUTHOR]

Amorphous indium‐gallium‐zinc‐oxide (a‐IGZO) based memristive devices with molybdenum contacts as both top and bottom electrodes are presented aiming to be used in neuromorphic applications. Devices down to 4 µm2 are fabricated using conventional photolithography processes, with an extraordinary yield of 100%. X‐ray photoelectron spectroscopy and transmission electron microscopy performed on the developed structures confirm the presence of a thin intermixed oxide layer (4–5 nm) containing Mo6+ oxidation state at the interface with the bottom contact. This results in Schottky diode‐like characteristics at the pristine state with a rectification ratio of 3 orders of magnitude. The devices have electroforming‐free and area‐dependent analog resistive switching properties. Temperature analysis of resistive switching I–V data reveals barrier height variations of the junction. Several synaptic functions, such as synaptic potentiation and depression as response to programmed pulses, short‐ to long‐term plasticity transition (STP to LTP) and "learning experience" properties are presented. The Mo/IGZO/Mo memristive device shows potential application of an electronic synapse for brain‐inspired computing application. Integration in System‐on‐Panel architectures is possible at negligible cost, because all materials are used in commercial IGZO thin‐film transistor fabrication. [ABSTRACT FROM AUTHOR]

The effect of substrate temperature on the direct current magnetron‐sputtered zirconium oxide (ZrO2) dielectric films was investigated. Stoichiometric of the ZrO2 thin films was obtained at an oxygen partial pressure of 4.0 × 10−2 Pa. X‐ray diffraction studies revealed that the crystallite size in the layer was increased from 4.8 to 16.1 nm with increase of substrate temperature from 303 to 673 K. Metal‐oxide‐semiconductor devices were fabricated on ZrO2/Si stacks with Al gate electrode. The dielectric properties of ZrO2 layer and interface quality at ZrO2/Si were significantly influenced by the substrate temperature. The dielectric constant increased from 15 to 25, and the leakage current density decreased from 0.12 × 10−7 to 0.64 × 10−9 A cm−2 with the increase of substrate temperature from 303 to 673 K. [ABSTRACT FROM AUTHOR]

Photonic front‐coatings with self‐cleaning properties are presented as means to enhance the efficiency and outdoor performance of thin‐film solar cells, via optical enhancement while simultaneously minimizing soiling‐related losses. This is achieved by structuring parylene‐C transparent encapsulants using a low‐cost and highly‐scalable colloidal‐lithography methodology. As a result, superhydrophobic surfaces with broadband light‐trapping properties are developed. The optimized parylene coatings show remarkably high water contact angles of up to 165.6° and extremely low adhesion, allowing effective surface self‐cleaning. The controlled nano/micro‐structuring of the surface features also generates strong anti‐reflection and light scattering effects, corroborated by numeric electromagnetic modeling, which lead to pronounced photocurrent enhancement along the UV–vis–IR range. The impact of these photonic‐structured encapsulants is demonstrated on nanocrystalline silicon solar cells, that show short‐circuit current density gains of up to 23.6%, relative to planar reference cells. Furthermore, the improvement of the devices' angular response enables an enhancement of up to 35.2% in the average daily power generation. [ABSTRACT FROM AUTHOR]

Solution combustion synthesis (SCS) has been widely used to produce simple and complex oxides with a desired morphology (size and shape). SCS is valuable due to low cost, simplicity and energy efficient synthesis. To guarantee the best molecular‐level mixing of reactants in an aqueous or solvent‐based solution some parameters need to be controlled, such as fuel type, metal cations precursors, stoichiometry ratio (φ), pH effect, atmosphere and initiation type. These determine the final properties of the oxide materials, providing the potential to reach different morphologies, which are essential for their final applications. This Review article focuses on the crucial parameters in SCS and how these affect the overall materials properties from nanostructures to thin films. To finalize, special attention is given to the application of SCS to form metal oxide thin films at low temperature and their application in thin film transistors (TFTs). [ABSTRACT FROM AUTHOR]

Lately, printed oxide electronics have advanced in the performance and low‐temperature solution processability that are required for the dawn of low‐cost flexible applications. However, some of the remaining limitations need to be surpassed without compromising the device electronic performance and operational stability. The printing of a highly stable ultra‐thin high‐κ aluminum‐oxide dielectric with a high‐throughput (50 m min−1) flexographic printing is accomplished while simultaneously demonstrating low‐temperature processing (≤200 °C). Thermal annealing is combined with low‐wavelength far‐ultraviolet exposure and the electrical, chemical, and morphological properties of the printed dielectric films are studied. The high‐κ dielectric exhibits a very low leakage‐current density (10−10 A cm−2) at 1 MV cm−1, a breakdown field higher than 1.75 MV cm−1, and a dielectric constant of 8.2 (at 1 Hz frequency). Printed indium oxide transistors are fabricated using the optimized dielectric and they achieve a mobility up to 2.83 ± 0.59 cm2 V−1 s−1, a subthreshold slope <80 mV dec−1, and a current ON/OFF ratio >106. The flexible devices reveal enhanced operational stability with a negligible shift in the electrical parameters after ageing, bias, and bending stresses. The present work lifts printed oxide thin film transistors a step closer to the flexible applications of future electronics. [ABSTRACT FROM AUTHOR]

Electronics on paper enable some specific applications out of conventional ones which require innovative approaches and concepts on the design of devices and systems. Within this context, this work demonstrates that a unique set of characteristics can be combined in planar dual-gate oxide-based field effect transistors with a back floating electrode using paper simultaneously as substrate and dielectric. The working principle of these transistors relies on the formation of electric double layers at the semiconductor/paper and paper/back floating electrode interfaces (associated to ions displacement within the paper) that can be disturbed by a voltage applied at a secondary gate, by the back floating potential or by the combination of both. This feature allows for the control of the on-voltage of the transistors, from depletion to enhancement mode, for instance. Moreover, this specific characteristic allows the implementation of universal logic gates (NAND and NOR) using only one transistor, by setting the proper combination of the voltage level applied at each gate. This way a simple and universal device architecture can be envisaged towards the simplification of the production of low power electronic systems on paper. [ABSTRACT FROM AUTHOR]

Abstract: The recent interest of electronic skin (e‐skin) has pushed the research toward the development of flexible sensors, namely, for pressure detection. Several mechanisms can be used to transduce pressure into electrical signals, but piezoresistivity presents advantages due to its simplicity. The microstructuration of the films composing these sensors is a common strategy to improve their sensitivity. As an alternative to conventional and expensive photolithography techniques and low customizable techniques based on natural molds, a novel strategy for the microstructuration of polydimethylsiloxane (PDMS) films is proposed, based on molds fabricated by laser engraving. After design optimization of these microstructured films, which relies on microcones, piezoresistive sensors with a limit of detection of 15 Pa and a sensitivity of −2.5 kPa−1 in the low‐pressure regime are obtained. These sensors are used with success on the detection of the blood pressure wave at the wrist, thus exhibiting a great potential for health applications. [ABSTRACT FROM AUTHOR]

Abstract: Zinc‐tin oxide (ZTO) is widely invoked as a promising indium and gallium‐free alternative for amorphous oxide semiconductor based thin‐film transistors (TFTs). The main bottleneck of this semiconductor material compared to mainstream indium‐gallium‐zinc oxide (IGZO) is centered in the larger processing temperatures required to achieve acceptable performance (>300 °C), not compatible with low‐cost flexible substrates. This work reports for the first time flexible amorphous‐ZTO TFTs processed at a maximum temperature of 180 °C. Different aspects are explored to obtain performance levels comparable to IGZO devices at these low processing temperatures, such as hydrogen incorporation during ZTO sputtering and integration with a high‐κ multilayer/multicomponent dielectric. Close‐to‐zero turn‐on voltage, field‐effect mobility ≈5 cm2 V−1 s−1, and subthreshold slope of 0.26 V dec−1 are obtained. Stability under negative‐bias‐illumination stress is dramatically improved with hydrogen incorporation in ZTO and device performance is insensitive to bending under a radius of curvature of 15 mm. Inverters using the ZTO TFTs enable rail‐to‐rail operation with supply voltage V DD as low as 5 V, while a differential amplifier with positive feedback loop provides a gain of 17 dB and unity gain frequency of 40 kHz, limited by the large gate‐to‐source and gate‐to‐drain overlaps used herein. [ABSTRACT FROM AUTHOR]

Abstract: The fabrication of functionalized 1D oxide fibers with accurate control of orientation, location, and number is highly demanded and challengeable based on current techniques, which hinder their practical application in opto/electronic devices. Herein, a rapid and simple method is developed to directly draw the oxide fibers from its polymer solution over large area. The draw‐spinning method enables the accurate positioning of individual fiber and the construction of complex patterns, holding great potentials in fiber‐based electronics. The assembled field‐effect transistors (FETs) based on single indium oxide (In2O3) fiber exhibit excellent current modulation capability with a high on/off current ratio of 106. Adjusting the number of fibers within the channel, the device performance can be modulated. Moreover, the draw‐spinning technique is applied to fabricate highly aligned fiber arrays by using brush pen. The FETs based on aligned In2O3 fiber arrays exhibit superior current‐driven capability compared with the devices with limited number of fibers. Their further integrations on high‐permittivity dielectric layer show improved device performance at an operating voltage of 4 V. This method is scalable and can be implemented easily to fabricate various functional fibers in both laboratory and industrial manufacturing. [ABSTRACT FROM AUTHOR]

Abstract: In this context, a simple, nontoxic, and eco‐friendly fully water‐induced (WI) route to fabricate ternary ZrGdOx thin films at various annealing temperatures is reported. Annealing temperature dependent microstructure, morphology, optical, electrical properties, and chemical bonding states of the WI ZrGdOx thin films are investigated by x‐ray diffraction, atomic force microscopy, optical spectroscopy, x‐ray photoelectron spectroscopy, and electrical measurements. A low leakage current density of 10−8 A cm−2 at 1 mV cm−1 and a large areal capacitance of 531 nF cm−2 at 20 Hz are observed for 400 °C‐annealed ZrGdOx thin films. To verify the possible applications of ZrGdOx thin films as the gate dielectric in thin‐film transistors (TFTs), WI In2O3/ZrGdOx TFTs are integrated. 250 °C‐derived full oxide In2O3/ZrGdOx TFTs have demonstrated high electrical performance and low operating voltage, including high µFE of 18.82 cm2 V−1 S−1, threshold voltage shift of 0.46 V under positive bias stress for 3600 s, and a large Ion/Ioff of 6.01 × 107, respectively. Finally, a low voltage resistor‐loaded unipolar inverter is built using In2O3/ZrGdOx TFT, exhibiting a linear relationship between supplied voltage and gain voltage and a maximum gain of 7.4 at 2.5 V. These optimized parameters have achieved a low operating voltage of 2 V, which represents a great step toward the achievement of low‐cost, low‐power consumption, and large‐area all‐oxide flexible electronics. [ABSTRACT FROM AUTHOR]

Abstract: Thin film solar cells based in Cu(In,Ga)Se2 (CIGS) are among the most efficient polycrystalline solar cells, surpassing CdTe and even polycrystalline silicon solar cells. For further developments, the CIGS technology has to start incorporating different solar cell architectures and strategies that allow for very low interface recombination. In this work, ultrathin 350 nm CIGS solar cells with a rear interface passivation strategy are studied and characterized. The rear passivation is achieved using an Al2O3 nanopatterned point structure. Using the cell results, photoluminescence measurements, and detailed optical simulations based on the experimental results, it is shown that by including the nanopatterned point contact structure, the interface defect concentration lowers, which ultimately leads to an increase of solar cell electrical performance mostly by increase of the open circuit voltage. Gains to the short circuit current are distributed between an increased rear optical reflection and also due to electrical effects. The approach of mixing several techniques allows us to make a discussion considering the different passivation gains, which has not been done in detail in previous works. A solar cell with a nanopatterned rear contact and a 350 nm thick CIGS absorber provides an average power conversion efficiency close to 10%. [ABSTRACT FROM AUTHOR]

The present work reports on the handwriting of electronic circuits on paper based on the deposition of an inorganic oxide semiconductor, exploiting the pen‐on‐paper (PoP) approach. The method relies on the use of a parallel metal plate pen, well known from calligraphy applications, which permits controlled deposition of a continuous zinc oxide (ZnO) dual‐phase layer on conventional printing paper. The hand‐drawn ZnO film exhibits a continuous and uniform surface with a thickness of roughly 1.5 µm, allowing the application as active layer for UV sensors and field effect transistors on paper. Photocurrent generated from the UV radiation reaches values up to 3.4 mA cm−2 with switching times on the order of few seconds. The final written paper transistors, where paper plays simultaneously the role of substrate and dielectric, reaches On/Off current ratios (IOn/IOff) of about two orders of magnitude and field effect mobility close to 5 × 10−3 cm2 V−1 s−1. As a final proof‐of‐concept a common source amplifier showing clear inverting characteristics is fabricated using a PoP written driving ZnO‐based transistor and a pencil‐drawn track as the load resistance. [ABSTRACT FROM AUTHOR]

A new concept for reusable eco-friendly hydrogel electrolytes based on cellulose is introduced. The reported electrolytes are designed and engineered through a simple, fast, low-cost, and eco-friendly dissolution method of microcrystalline cellulose at low temperature using an aqueous LiOH/urea solvent system. The cellulose solution is combined with carboxymethyl cellulose, followed by the regeneration and simultaneous ion incorporation. The produced free standing cellulose-based electrolyte films exhibit interesting properties for application in flexible electrochemical devices, such as biosensors or electrolyte-gated transistors (EGTs), because of their high specific capacitances (4-5 µF cm−2), transparency, and flexibility. Indium-gallium-zinc-oxide EGTs on glass with laminated cellulose-based hydrogel electrolytes (CHEs) as the gate dielectric are produced presenting a low working voltage (<2 V), showing an on-off current ratio ( Ion/off) of 106, a subthreshold swing lower than 0.2 V dec−1, and saturation mobility (μSat) reaching 26 cm2 V−1 s−1. The flexible CHE-gated transistors on paper are also demonstrated, which operate at switching frequencies up to 100 Hz. Combining the flexibility of the EGTs on paper with the reusability of the developed CHEs is a breakthrough toward biodegradable advanced functional materials allied with disposable/recyclable and low-cost electronic devices. [ABSTRACT FROM AUTHOR]

Solution‐processed oxide semiconductor and dielectric thin films have been widely studied for achieving flexible, high‐performance, and low‐power electronics and circuits. In this report, high‐k HfO2 dielectrics and amorphous ZnSnO (ZTO) semiconductors are synthesized via a simple and facile redox reaction by introducing perchloric acid (HClO4, PA) as oxidizer to eliminate the Cl residuals. Thermogravimetric analysis indicates that the thermal decomposition of PA‐involved HfCl4(PA‐HfO2) xerogel is completed at 350 °C, whereas the decomposition temperature of pristine HfCl4 xerogel is higher than 450 °C. The optical, structural, morphological, compositional, and electrical properties of PA‐HfO2 and the pristine HfO2 dielectric films are investigated systematically. Meanwhile, by using chloride elimination reaction, PA‐ZTO semiconducting thin films are fabricated at various temperatures and their applications in thin‐film transistors (TFTs) are examined. Furthermore, the optimized PA‐ZTO channel layer is fabricated on PA‐HfO2 dielectric. The resulting device exhibits high electrical performance and operational stability at a low voltage of 2 V, including high saturation mobility of 13.2 cm2 V−1 s−1, small subthreshold slope of 70 mV dec−1, current ratio of 108, and threshold voltage shift of 0.05 V under positive bias stress for 3000 s. Finally, a low‐voltage resistor‐loaded inverter is built using PA‐ZTO/PA‐HfO2 TFT, exhibiting a linear relationship between supplied voltage and gain voltage and a maximum gain of 11 at 2.5 V. [ABSTRACT FROM AUTHOR]

The post-deposition modification of ZnO-based transparent conductive oxides (TCOs) can be the key to produce thin films with optoelectronic properties similar to indium tin oxide (ITO), but at a much lower cost. Here, we present electro-optical results achieved for post-deposition annealing of Al-Zn-O (AZO), AZO:H, Ga-Zn-O:H (GZO:H), and Zn-O:H (ZNO:H) thin films deposited by RF sputtering at room temperature. These studies comprise results of thermal annealing at atmospheric pressure, vacuum, forming gas, H2 and Ar atmospheres, and H2 and Ar plasmas, which lead to significant enhancement of their electro-optical properties, which are correlated to morphological and structural improvements. The post-deposition annealing leads to an enhancement in resistivity above 40% for AZO, AZO:H, and GZO:H, reaching ρ ≈ 2.6-3.5 × 10−4 Ωcm, while ZnO:H showed a lower improvement of 13%. The averaged optical transmittance in the visible region is about 89% for the investigated TCOs. Such results match the properties of state-of-art ITO ( ρ ≈ 10−4 Ωcm and transmittance in VIS range of 90%) employing much more earth-abundant materials. [ABSTRACT FROM AUTHOR]

High‐k alkaline lithium oxide (LiOx) thin films are fabricated by spin‐coating method. The LiOx thin films are annealed at different temperatures and characterized by various techniques. An optimized LiOx dielectric is achieved at an annealing temperature of 300 °C and exhibits wide bandgap of ≈5.5 eV, smooth surface, relatively permittivity of ≈6.7, and low leakage current density. The as‐fabricated LiOx thin films are integrated, as gate dielectrics, in both n‐channel indium oxide (In2O3) and p‐channel cupric oxide (CuO) transistors. The optimized In2O3/LiOx thin‐film transistor (TFT) exhibits high performance and high stability, such as Ion/Ioff of 107, electron mobility of 5.69 cm2 V−1 s−1, subthreshold swing of 70 mV dec−1, negligible hysteresis, and threshold voltage shift of 0.1 V under bias stress for 1.5 h. Meanwhile, the p‐channel CuO TFT based on LiOx dielectric shows high Ion/Ioff of 105 and hole mobility of 1.72 cm2 V−1 s−1. All the electrical performances are achieved at an ultra‐low operating voltage of 2 V. Considering the simple procedure, the moderate annealing temperature, and the low power consumption merits, these outstanding characteristics represent a significant advance toward the development of battery compatible and portable electronics. [ABSTRACT FROM AUTHOR]

In this paper, the role of electrode architecture (conventional and interdigital), device structure (vertical or planar), and tungsten oxide (WO3) channel thickness on the electro‐optical performances of room temperature sputtered electrochromic transistors (EC‐Ts) is reported. A larger number of electro‐reducible tungsten sites in thicker WO3 films provide improved optical density and coloration efficiency. However, overall transistor performance is found to suffer in planar EC‐Ts with the conventional electrode architecture, where the step to planar interdigital electrodes leaves the devices to be almost insensitive to WO3 thickness. Vertical structures result in improved device properties and stability, given to the shorter distance between gate electrode and semiconductor and to the encapsulation effect provided by such structures. These devices show an On–Off ratio of 5 × 106 and a transconductance (g m) of 3.59 mS, for gate voltages (V G) between −2 and 2 V, which to the authors' knowledge are the best values ever reported for electrochemical transistors. The simple and low‐cost processing together with the electrical/optical performances well supported into a comprehensive analysis of device physics opens doors for a wide range of new applications in display technologies, biosensors, fuel cells, or electrochemical logic circuits. [ABSTRACT FROM AUTHOR]

Solution-processed metal-oxide thin films based on high dielectric constant (k) materials have been extensively studied for use in low-cost and high-performance thin-film transistors (TFTs). Here, scandium oxide (ScOx) is fabricated as a TFT dielectric with excellent electrical properties using a novel water-inducement method. The thin films are annealed at various temperatures and characterized by using X-ray diffraction, atomic-force microscopy, X-ray photoelectron spectroscopy, optical spectroscopy, and a series of electrical measurements. The optimized ScOxthin film exhibits a low-leakage current density of 0.2 nA cm−2 at 2 MV cm−1, a large areal capacitance of 460 nF cm−2 at 20 Hz and a permittivity of 12.1. To verify the possible applications of ScOx thin films as the gate dielectric in complementary metal oxide semiconductor (CMOS) electronics, they were integrated in both n-type InZnO (IZO) and p-type CuO TFTs for testing. The water-induced full oxide IZO/ScOx TFTs exhibit an excellent performance, including a high electron mobility of 27.7 cm2 V−1 s−1, a large current ratio (IonIoff) of 2.7 × 107 and high stability. Moreover, as far as we know it is the first time that solution-processed p-type oxide TFTs based on a high-k dielectric are achieved. The as-fabricated p-type CuO/ScOx TFTs exhibit a large IonIoff of around 105 and a hole mobility of 0.8 cm2 V−1 at an operating voltage of 3 V. To the best of our knowledge, these electrical parameters are among the highest performances for solution-processed p-type TFTs, which represents a great step towards the achievement of low-cost, all-oxide, and low-power consumption CMOS logics. [ABSTRACT FROM AUTHOR]

When thinking on low cost and sustainable electronic systems, paper can be considered as an interesting option to be used as substrate but also as a component of such systems. In this work we have tailored paper samples that were used simultaneously as physical support and dielectric in oxide based paper field effect transistors (FETs). It was observed that the gate leakage current in these devices depends directly from fibril's dimension and arrangement, being lower for micro/nano fibrillated cellulose paper. Moreover, extra ionic charge added to the paper during its production results in the improvement of FETs' electrical properties, with saturation mobility of 16 cm 2V -1s -1 and on/off current ratio close to 105. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

The present development of non-wafer-based photovoltaics (PV) allows supporting thin film solar cells on a wide variety of low-cost recyclable and flexible substrates such as paper, thereby extending PV to a broad range of consumer-oriented disposable applications where autonomous energy harvesting is a bottleneck issue. However, their fibrous structure makes it challenging to fabricate good-performing inorganic PV devices on such substrates. The advances presented here demonstrate the viability of fabricating thin film silicon PV cells on paper coated with a hydrophilic mesoporous layer. Such layer can not only withstand the cells production temperature (150 °C), but also provide adequate paper sealing and surface finishing for the cell's layers deposition. The substances released from the paper substrate are continuously monitored during the cell deposition by mass spectrometry, which allows adapting the procedures to mitigate any contamination from the substrate. In this way, a proof-of-concept solar cell with 3.4% cell efficiency (41% fill factor, 0.82 V open-circuit voltage and 10.2 mA cm−2 short-circuit current density) is attained, opening the door to the use of paper as a reliable substrate to fabricate inorganic PV cells for a plethora of indoor applications with tremendous impact in multi-sectorial fields such as food, pharmacy and security. [ABSTRACT FROM AUTHOR]

ABSTRACT The use of microfluidics platforms combined with the optimal optical properties of gold nanoparticles has found plenty of application in molecular biosensing. This paper describes a bio-microfluidic platform coupled to a non-cross-linking colorimetric gold nanoprobe assay to detect a single nucleotide polymorphism associated with increased risk of obesity fat-mass and obesity-associated (FTO) rs9939609 (Carlos et al., 2014). The system enabled significant discrimination between positive and negative assays using a target DNA concentration of 5 ng/µL below the limit of detection of the conventionally used microplate reader (i.e., 15 ng/µL) with 10 times lower solution volume (i.e., 3 µL). A set of optimization of our previously reported bio-microfluidic platform (Bernacka-Wojcik et al., 2013) resulted in a 160% improvement of colorimetric analysis results. Incorporation of planar microlenses increased 6 times signal-to-loss ratio reaching the output optical fiber improving by 34% the colorimetric analysis of gold nanoparticles, while the implementation of an optoelectronic acquisition system yielded increased accuracy and reduced noise. The microfluidic chip was also integrated with a miniature fiber spectrometer to analyze the assays' colorimetric changes and also the LEDs transmission spectra when illuminating through various solutions. Furthermore, by coupling an optical microscope to a digital camera with a long exposure time (30 s), we could visualise the different scatter intensities of gold nanoparticles within channels following salt addition. These intensities correlate well to the expected difference in aggregation between FTO positive (none to small aggregates) and negative samples (large aggregates). Biotechnol. Bioeng. 2015;112: 1210-1219. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Here, a simple, nontoxic, and inexpensive 'water-inducement' technique for the fabrication of oxide thin films at low annealing temperatures is reported. For water-induced (WI) precursor solution, the solvent is composed of water without additional organic additives and catalysts. The thermogravimetric analysis indicates that the annealing temperature can be lowered by prolonging the annealing time. A systematic study is carried out to reveal the annealing condition dependence on the performance of the thin-film transistors (TFTs). The WI indium-zinc oxide (IZO) TFT integrated on SiO2 dielectric, annealed at 300 °C for 2 h, exhibits a saturation mobility of 3.35 cm2 V−1 s−1 and an on-to-off current ratio of ≈108. Interestingly, through prolonging the annealing time to 4 h, the electrical parameters of IZO TFTs annealed at 230 °C are comparable with the TFTs annealed at 300 °C. Finally, fully WI IZO TFT based on YO x dielectric is integrated and investigated. This TFT device can be regarded as 'green electronics' in a true sense, because no organic-related additives are used during the whole device fabrication process. The as-fabricated IZO/YO x TFT exhibits excellent electron transport characteristics with low operating voltage (≈1.5 V), small subthreshold swing voltage of 65 mV dec−1 and the mobility in excess of 25 cm2 V−1 s−1. [ABSTRACT FROM AUTHOR]

In the architecture described, cuprous oxide (Cu2O) is tamed to be highly (111) plane oriented nanostructure through adjusting the deposition postulate by glancing angle deposition technique. In the controlled atmosphere oxygen vacancy is introduced into the Cu2O crystal subsequently fostering an impurity energy state ( Eim) close to the conduction band. Our model of Cu2O electronic structure using density functional theory suggests that oxygen vacancies enhance the electron donating ability because of unshared d-electrons of Cu atoms (nearest to the vacancy site), allowing to pin the work function energy level around 0.28 eV compared to the bulk. This result is also complemented by Kelvin probe force microscopy analysis and X-ray photoelectron spectroscopy method. Oxygen vacancy in Cu2O (Cu2O1- δ) exhibits promising field emission properties with interesting field electron tunneling behavior at different applied fields. The films show very low turn-on and threshold voltages of value 0.8 and 2.4 V μm−1 respectively which is influenced by the oxygen vacancy. Here, a correlation between the work function modulation due to the oxygen vacancy and enhancement of field emission of Cu2O1- δ nanostructure is demonstrated. This work reveals a promising new vision for Cu2O as a low power field emitter device. [ABSTRACT FROM AUTHOR]