In this paper, we report the effect of the write voltage and frequency on memristor-based resistive random access memory (RRAM). The above-said parameters have been investigated on the linear drift model of the memristor. With a variation of write voltage from 0.2 to 1.2 V and a subsequent frequency modulation from 1, 2, 4, 10, 100 and 200 Hz, the corresponding effects on memory window, low resistance state (LRS) and high resistance state (HRS) have been reported. Thus, the lifetime (τ) reliability analysis of memristor-based RRAM is carried out using the above results. It is found that the HRS is independent of the write voltage, whereas LRS shows dependency on write voltage and frequency. The simulation results showcase the fact that the memristor possesses higher memory window and lifetime (τ) in the higher voltage with lower frequency region, which has been attributed to less data losses in the memory architecture.

In this work, we employed an easy hydrothermal method to prepare CuO and ZnO, as well as the prepared composite nanostructured electrodes of CuO@ZnO for supercapacitor applications. The systematic electrochemical performance evaluation of the prepared materials was conducted by cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS). CuO@ZnO nanocomposite reflected the best charge storing behavior with a specific capacitance of 513 F/g, followed by pristine CuO (190 F/g) and ZnO (416 F/g). The composite also demonstrated 25.67 Wh/kg and 400 W/kg for energy density and power density, respectively, suggesting improved electrochemical performance. Besides, the areal and volumetric capacitances were 0.77 F/cm² and 4.81 F/cm³, respectively, supported by the structural integrity and enhancement in electroactive materials utilization of the electrode material. Kinetic analysis showed that b values of the samples had mixed capacitive/diffusion-controlled charge storage, while higher diffusion coefficients and standard rate constants were apparent for ion transport or redox kinetics. EIS results showed a 2.14 Ω solution resistance, indicative of a decreased electrical resistivity. An asymmetric supercapacitor device fabricated by CuO@ZnO as the positive electrode and activated carbon (AC) as the negative electrode provided the specific capacitance of 48.57 F/g, energy density of 15.17 Wh/kg, and power density of 535 W/kg. After 10,000 cycles, the capacitance of the device was 76%, indicating good long-term stability.

Reliable detection of SO ₂ at low operating temperatures remains a significant challenge for metal oxide gas sensors, particularly in harsh refinery environments where selectivity and stability are critical. In this study, ZnFe ₂ O ₄ thin films with compact and porous morphologies are deposited via spray pyrolysis to investigate their suitability for SO ₂ sensing in refinery environments. The rigorous structural analysis reveals a strong correlation between crystalline features and sensing performance. In particular, an increased degree of spinel inversion enhances the sensor response by facilitating charge transport and surface reactivity. The porous films exhibit superior sensing behavior compared to compact films, owing to their higher surface area and increased availability of active adsorption sites. The optimized ZP375 sensor demonstrates a linear response towards SO ₂ concentration up to 200 ppm, with a low detection limit of 0.41 ppm. The sensor exhibits optimal performance at an operating temperature of 150°C and demonstrates excellent selectivity towards SO ₂ in the presence of other common interfering gases typically encountered in refinery environments. The sensor further exhibits long‐term stability extended up to 30 days. The results highlight the potential of spray‐deposited ZnFe ₂ O ₄ thin films as robust and energy‐efficient sensing materials for SO ₂ monitoring in industrial emissions from petrochemical refineries.