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In this present study, CuO/TiO2/rGO (CTG) hybrid ternary composite was synthesized via a single-step hydrothermal route for an asymmetric supercapacitor application. The PXRD pattern and XPS analysis confirms the formation of prepared ternary composites. As analyzed by FE-SEM and HR-TEM techniques, both CuO and TiO2nanoparticles were anchored on the conducting two-dimensional rGO matrix, which facilitates efficient electron transport during electrochemical tests. From the electrochemical investigations, the CTG-2 composite revealed a high rise in capacitance value of 1077 Fg-1, overcoming the individual capacitance of CuO (173.4 Fg-1), TiO2(206.2 Fg-1), rGO (269 Fg-1), and composite CTG-1 (690 Fg-1) at a current density of 1 Ag-1with an unveiled remarkable capacitance performance of 88.4 % over the 5000 cycles at 5 Ag-1. Further, an asymmetric supercapacitor device was also assembled in two-electrode system with a specific capacitance of 563.7 Fg-1at 1 Ag-1, with an energy and power density of 50.2 Wh Kg-1and 498.2 W Kg-1. This research provides a novel approach for synthesizing CTG ternary nanocomposite, which could have an impact on contemporary electrical vehicles and portable electronics that are used for energy storage applications.

Energy demand is increasing day by day globally due to the increase of population in a drastic manner. Solar energy a renewable, abundant, eco-friendly energy is the best solution to meet the energy demand of the world. The dye-sensitized solar cells (DSSC) are the most reliable of the photovoltaics (PV) on account of their facile fabrication and pricing. Here a novel quaternary hybrid nanocomposite was substituted in the place of platinum (Pt) as a counter electrode and yielded exceptional results. The reduced graphene oxide/ manganese dioxide/ copper oxide/ cobalt oxide (rGO/MnO2/CuO/Co3O4(RMCC)) was prepared and employed as a counter electrode of the DSSC under varied photoanodes (PA) like as-synthesized titanium dioxide (TiO2), zinc Oxide (ZnO) and titanium dioxide/zinc oxide TiO2/ZnO with N-719 as dye medium, all coated over Fluorine doped tin oxide (FTO) glass as substrate. The DSSC constructed with RMCC as counter electrode (CE) was discovered to have a reliable photoconversion efficiency of 7.67 % which is 98.83 % of the Platinum substituted DSSC. The result was also testified by developing 60 such devices in total, under different photoanode material and was proved to be consistent, enabling the nanocomposite to develop into a positive example for CE in DSSC. Later this DSSC was integrated with a symmetric supercapacitor made of the same electrode material and gave a photovoltage of 0.828 V with areal-specific capacitance, energy and power density of 264.73 mF cm−2, 25.208 μW h cm−2and 0.1656 mW cm−2, respectively. The photo-supercapacitor device self-discharged at 548 s with an overall conversion efficiency of the photosupercapacitor is 8.98 % resulting in a self-charged energy device.

In this study, a novel photocatalyst composed of zinc ferrite (ZnFe₂O₄), titanium dioxide (TiO₂), and multi-walled carbon nanotubes (MWCNTs) was successfully synthesized via the hydrothermal method, and evaluated for the degradation of ampicillin (AMP) in aqueous solutions. The synthesized nanocomposites were thoroughly characterized using various analytical techniques, including XRD, HR-SEM, HR-TEM, EDX, UV-Vis, FT-IR, BET, and XPS analysis. Crystallite sizes of 24.18 nm for ZnFe₂O₄ and 17.8 nm for TiO₂ were determined. The composite exhibited a band gap of 1.4 eV, indicating its enhanced photocatalytic activity. The photocatalytic performance was assessed under varying conditions, including different nanocomposite dosages (0.3–1 g/L), AMP concentrations (10–50 mg/L), and pH values (2–12). The optimal AMP degradation efficiency of 99.2 % was achieved using 0.7 g/L of the photocatalyst, 10 mg/L of AMP, and a pH of 12 under 90 min of solar irradiation. These optimal parameters were then applied to evaluate AMP degradation using ZnFe2O4, TiO2, and ZnFe2O4/MWCNTs individually, with the degradation rate analyzed using a pseudo-first-order model. The superior photocatalytic efficiency can be primarily attributed to improved charge transfer dynamics and effective electron-hole separation, enabled by the doping of MWCNTs. Hydroxyl radicals (OH•) were identified as the primary reactive species responsible for AMP degradation. Furthermore, the catalyst retained 91 % of its photocatalytic efficiency after eight consecutive cycles, demonstrating excellent stability and reusability. These results underscore the potential of the ZnFe₂O₄/MWCNTs/TiO₂ composite as a highly effective and sustainable photocatalyst for removing pharmaceutical pollutants from aquatic environments.