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ZnO films were grown on sapphire (001) substrate by atmospheric MOCVD using diethyl zinc and tertiary butanol precursors. The influence of different carrier gases (H2 and He) on the properties was analyzed by their structural (XRD), microstructural (SEM) and compositional (SIMS) characterization. The intensity of the strongest diffraction peak from ZnO (002) plane was increased by about 2 orders of magnitude when He is used as carrier gas, indicating the significant enhancement in crystallinity. The surface of the samples grown using H2 and He carrier gases was composed of leaf-like and spherical grains respectively. Hydrogen [H] content in the film grown using H2 is higher than that using He, indicating that the [H] was influenced by the H2 carrier gas. Ultraviolet emission dominates the low temperature PL spectra. The emission from ZnO films grown using He show higher optical quality and more emission centers.Se depositaron películas de ZnO sobre sustratos de zafiro (001) utilizando dietil zinc y butanol terciario como precursores. La influencia de los diferentes gases portadores (H2 y He) sobre las propiedades se estudió mediante la caracterización estructural (XRD), microestructural (SEM) y composicional (SIMS). La intensidad del pico de difracción más importante del plano (002) del ZnO aumentó en dos órdenes de magnitud cuando se utiliza He como gas portador indicando un incremento significativo de la cristalinidad. La superficie de las muestras crecidas utilizando H2 y He está formada por granos en forma de hoja y de forma esférica respectivamente. El contenido en hidrógeno (H) en la película es mayor cuando se utiliza H2 que cuando se utiliza He, indicando que la cantidad de hidrógeno está influenciada por el H2 del gas portador. La emisión ultravioleta domina el espectro PL de baja temperatura. La emisión de las películas de ZnO utilizando He muestra mayor calidad óptica y más centros de emisión.

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]

In this study, a novel approach was used for the preparation of α-Fe2O3 films via electrodeposition followed by hydrothermal treatment for different time periods. The impacts of the time taken for hydrothermal treatment on the structure and morphology of the electrodeposited films were investigated. According to the X-ray diffraction and Raman spectroscopy results, the alpha structure type showed a unique pure phase. The α-Fe2O3 possessing two phases was revealed for the nanoparticles coated with nanorods by scanning electron microscopy. The energy dispersive X-ray microscopy displayed a remarkable decrease in the intensity of the Tin element due to the formation of nanorods on the nanoparticles. The results showed that the ascending increase in the time for hydrothermal treatment led to significant changes in film morphology and chemical composition with a direct consequence on the photocatalytic performance. The α-Fe2O3 films exhibited high efficiency towards the degradation of methylene blue, which was attributed to its structure. [ABSTRACT FROM AUTHOR]

Academic and industrial efforts have focused on developing energy storage devices for wearable and portable electronics using low-cost, scalable, and sustainable materials and approaches. In this work, commercially available stretch-broken carbon fiber yarns (SBCFYs) were hybridized with mixed phases of 1 T and 2H MoS2 nanosheets via conventional and microwave-assisted heating (CAH, MAH) without the use of binders to fabricate symmetric freestanding 1D fiber-shaped supercapacitors (FSCs). Electrochemical characterization performed in a three-electrode configuration showed promising results with specific capacitance values of 184.41 and 180.02 F·g−1, at 1 mV·s−1 for CAH and MAH, respectively. Furthermore, after performing 3000 CV cycles at 100 mV·s−1, the capacitance retention was 79.5% and 95.7%, respectively. Using these results as a reference, symmetric 1D FSCs were fabricated by pairing hybridized SBCFYs with MoS2 by MAH. The devices exhibited specific capacitances of approximately 58.60 ± 3.06 F·g−1 at 1 mV·s−1 and 54.81 ± 7.34 F·g−1 at 0.2 A·g−1 with the highest power density achieved being 15.17 W·g−1 and energy density of 5.06×10–4 Wh·g−1. In addition, five 1D FSCs were hand-stitched and connected in series onto a cotton fabric. These supercapacitors could power a temperature and humidity sensor for up to six minutes, demonstrating the practicality and versatility of the prepared 1D FSCs for powering future electronic systems. [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]