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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. 

In this paper, we investigate the effects of operational conditions on structural, electronic and electrochemical properties on molybdenum suboxides (MoO3-δ) thin films. The films are prepared using pulsed-laser deposition by varying the deposition temperature (Ts), laser fluence (Φ), the partial oxygen pressure (PO2) and annealing temperature (Ta). We find that three classes of samples are obtained with different degrees of stoichiometric deviation without post-treatment: (i) amorphous MoO3-δ (δ < 0.05) (ii) nearly-stoichiometric samples (δ ≈ 0) and (iii) suboxides MoO3-δ (δ > 0.05). The suboxide films 0.05 ≤ δ ≤ 0.25 deposited on Au/Ti/SiO2/flexible-Si substrates with appropriate processing conditions show high electrochemical performance as an anode layer for lithium planar microbatteries. In the realm of simple synthesis, the MoO3-δ film deposited at 450 °C under oxygen pressure of 13 Pa is a mixture of α-MoO3 and Mo8O23 phases (15:85). The electrochemical test of the 0.15MoO3-0.85Mo8O23 film shows a specific capacity of 484 µAh cm−2 µm−1 after 100 cycles of charge-discharge at a constant current of 0.5 A cm−2 in the potential range 3.0-0.05 V. 

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.