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Abstract The design and development of solar‐blind photodetectors utilizing ultrawide bandgap semiconductors have garnered significant attention due to their extensive utility in specialty commercial sectors. Solar‐blind photodetectors that display excellent photosensitivity, fast response time and are produced using cost‐effective fabrication steps will fulfill the performance demands in relevant applications. Herein, highly textured Sn‐doped Ga₂O₃thin film metal‐semiconductor‐metal type deep‐UV photodetectors using a commercially scalable magnetron sputtering method are reported. Commercially achievable growth and fabrication steps are intentionally chosen to demonstrate an economically viable photodetection workflow without compromising the device's performance. In‐depth structural, morphological, chemical, and optical characterization are reported to optimize the configuration for further device fabrication and testing. Under transient triggering circumstances, a fast response time of ≈500 ms is reported, accompanied by a responsivity of ≈60.5 A W⁻¹. The detectivity, external quantum efficiency, and photo‐to‐dark current ratio values are reported as 1.6 × 10¹³Jones, 2.8 × 10⁴%, and 17.4, respectively. The overall device performance and cost‐effective fabrication process for solar‐blind UV photodetection using Sn‐doped Ga₂O₃is promising. The approach holds promise for significant implications toward the development of electronics capable of functioning in extreme environments and exhibits substantial potential for enhancing low‐cost UV photodetector technology. 

Abstract Herein, the significant impact of the spin‐coated Cr₂O₃interface layer on the electrical properties and performance characteristics of Au/undoped‐InP (Au/InP) Schottky diodes (SD) is reported. The material characterization of spin‐coated Cr₂O₃films using a wide variety of analytical techniques, namely, atomic force microscopy, field emission scanning electron microscope, X‐ray diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopy, indicate the formation of hexagonal phase, nanocrystalline, and stoichiometric Cr₂O₃on InP. Optical absorption measurements reveal a bandgap of ≈3.5 eV. In‐depth analyses and detailed measurements of current‐voltage (I–V) and capacitance‐voltage (C‐V) employed to assess the interface characteristics and electrical performance of the Au/InP (SD) versus Au/Cr₂O₃/InP (MIS) devices. Compared to SD, MIS revealed superior rectifying properties. Indicating that the Cr₂O₃interface layer significantly influences the barrier height (Φ_BH) of SD, the estimated Φ_BH(0.64 eV (I–V)/0.86 eV (C‐V)) is higher than that of SD (0.57 eV (I–V)/0.67 eV (C‐V)). In addition, Cheungs and Nordes' methods are used to obtain the Φ_BH, ideality factor (n), and series resistance (R_S). The equivalent Φ_BHvalues obtained from current–voltage, Cheungs, and Nordes methods demonstrate stability and dependability in addition to validating their superior characteristics of MIS devices. The interface state density (N_SS) for MIS is lower than the SD's, indicating that the effectiveness of Cr₂O₃layer significantly reduces N_SS. Analyses to probe the mechanism demonstrate that, in SD and MIS, the Schottky emission controls the higher bias area, while the Poole‐Frenkel emission dominates the reverse conduction mechanism at the lower bias region. The present work convincingly demonstrates the potential application of the Cr₂O₃interfacial layer in delivering the enhanced performance and contributes to the progression of electrical devices for emerging electronics and energy‐related applications. 

Abstract An extensive examination of the nanoscale, crystallographic growth dynamics of the system, which is impacted by the thermal energy given to the GaN, is carried out to derive a deeper understanding of the growth kinetics, morphology and microstructure evolution, chemical bonding, and optical properties of Ga─O─N films. Thermal annealing of GaN films is performed in the temperature range of 900–1200 °C. Crystal structure, phase formation, chemical composition, surface morphology, and microstructure evolution of Ga─O─N films are investigated as a function of temperature. Increasing temperature induces surface oxidation, which results in the formation of stable β‐Ga₂O₃phase in the GaN matrix, where the overall film composition evolves from nitride (GaN) to oxynitride (Ga─O─N). While GaN surfaces are smooth, planar, and featureless, oxidation induced granular‐to‐rod shaped morphology evolution is seen with increasing temperature to 1200 °C. The considerable texturing and stability of the nanocrystalline Ga─O─N on Si substrates can be attributed to the surface and interface driven modification because of thermal treatment. Corroborating with structure and chemical changes, Raman spectroscopic analyses also indicate that the chemical bonding evolution progresses from fully Ga─N bonds to Ga─O─N. While the GaN oxidation process starts with the formation of β‐Ga₂O₃at an annealing temperature of 1000 °C, higher annealing temperatures induce structural distortion with the potential formation of Ga─O─N bonds. The structure‐phase‐chemical composition correlation, which will be useful for nanocrystalline materials for selective optoelectronic applications, is established in Ga─O─N films made by thermal treatment of GaN. 

Abstract For the sustainable growth of future generations, energy storage technologies like supercapacitors and batteries are becoming more and more common. However, reliable and high‐performance materials’ design and development is the key for the widespread adoption of batteries and supercapacitors. Quantum dots with fascinating and unusual properties are expected to revolutionize future technologies. However, while the recent discovery of quantum dots honored with a Nobel prize in Chemistry, their benefits for the tenacious problem of energy are not realized yet. In this context, herein, chemical‐composition tuning enabled exceptional performance of NiCo₂O₄(NCO)/graphene quantum dots (GQDs) is reported, which outperform the existing similar materials, in supercapacitors. A comprehensive study is performed on the synthesis, characterization, and electrochemical performance evaluation of highly functional NCO/GQDs in supercapacitors delivering enhanced energy efficiency. The high‐performance, functional NCO/GQDs electrode materials are synthesized by the incorporation of GQDs into NCO. The effect of variable amount of GQDs on the energy performance characteristics of NCO/GQDs in supercapacitors is studied systematically. In‐depth structural and chemical bonding analyses using X‐ray diffraction (XRD) and Raman spectroscopic studies indicate that all the NCO/GQDs composites crystallize in the spinel cubic phase of NiCo₂O₄while graphene integration evident in all the NCO/GQDs. The scanning electron microscopy imaging analysis reveals homogeneously distributed spherical particles with a size distribution of 5–9 nm validating the formation of QDs. The high‐resolution transmission electron microscopy analyses reveal that the NCOQDs are anchored on graphene sheets, which provide a high surface area of 42.27 m²g⁻¹and high mesoporosity for the composition of NCO/GQDs‐10%. In addition to establishing reliable electrical connection to graphene sheets, the NCOQDs provide reliable 3D‐conductive channels for rapid transport throughout the electrode as well as synergistic effects. Chemical‐composition tuning, and optimization yields NCO/GQDs‐10% to deliver the best specific capacitance of 3940 Fg⁻¹at 0.5 Ag⁻¹, where the electrodes retain ≈98% capacitance after 5000 cycles. The NCO/GQD‐10%//AC asymmetric supercapacitor device demonstrates outstanding energy density and power density values of 118.04 Wh kg⁻¹and 798.76 W kg⁻¹, respectively. The NCO/GQDs‐10%//NCO/GQDs‐10% symmetric supercapacitor device delivers excellent energy and power density of 24.30 Wh kg⁻¹and 500 W kg⁻¹, respectively. These results demonstrate and conclude that NCO/GQDs are exceptional and prospective candidates for developing next‐generation high‐performance and sustainable energy storage devices. 

Currently, the rapidly growing population is producing hazardous waste materials at an unprecedented rate, which seriously affects the global environment. Additionally, increasing population and pollution have amplified the need for renewable energy and efficient energy-storage technologies. One strategy is to implement greener processes for efficiency and/or utilize the waste generated for useful domestic and industrial applications. In this context, here, we harnessed the most littered environmental pollutant, cigarette filter waste (CFW), to synthesize carbon nanomaterials (CNM) via a single-step pyrolysis process, devoid of any catalyst or activating agent, possessing optimal characteristics for serving as an active electrode material in the fabrication of cutting-edge supercapacitors, thereby addressing the issue of waste recycling and the need for energy storage devices among the populace. Supercapacitors, namely SC-1 to SC-4 matching electrolytes, 1M H2SO4, 2M H2SO4, 1M KOH, and 2M KOH, fabricated using CNM electrodes were evaluated. Among these, SC-2 exhibits superior performance, demonstrating a remarkable capacitance of 240 Fg–1 at low scan rates (2 mVs–1), an enhanced energy density (22.4 Whkg–1), and commendable power density (399.43 Wkg–1). Furthermore, SC-2 maintained 5000 cycles of outstanding stability with 97.8% capacitance retention. This study unveils the potential of CFW-derived CNMs as an electrode material for the realization of state-of-the-art supercapacitors. 

This study explores and presents a comprehensive understanding of the synergistic effect of in situ formed TiO2 in Ti2C MXene (TTMXene) nanomaterials to derive enhanced energy characteristics in high-performance flexible symmetric supercapacitors. The TTMXene two-dimensional (2D) (nanocomposite) materials were synthesized by a simple single-step chemical etching method. The TTMXene thus formed exhibits a layered structure with an average particle size in the range of 10−50 nm. The electrochemical studies demonstrate that the TTMXene nanocomposite exhibits a specific capacitance of 729 F g−1 at a current density of 0.5 A g−1 . This enhanced performance is due to utilizationofa highactivesurfaceareaand excellentelectronicconductivityofthe in-situ formed TiO2 in Ti2C MXene. The prototype of a flexible symmetric TTMXene supercapacitor was fabricated and characterized. The TTMXene// TTMXenedemonstratedanexcellentenergydensityof152.3Whkg−1 atapower density of 0.215 kW kg−1 and retained 88% specific capacitance after 10,000 cycles. These findings highlight that the TTMXene nanocomposites are exceptional candidates for future flexible supercapacitor devices with long-term and superior performance.