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Europium vanadate (EuVO4) nanorods were synthesized via the facile solvothermal route by using europium oxide as europium (Eu) source and ammonium metavanadate as vanadium (V) source. The synthesized EuVO4 nanorods were characterized by X-ray diffraction spectrum (XRD), Fourier transform spectroscopy (FTIR), micro-Raman spectroscopy, scanning electron microscope (SEM), high-resolution transmission electron microscope (HRTEM), energy dispersive X-ray analyses (EDX), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), ultraviolet (UV)–visible absorption spectrum, and photoluminescence (PL) to find the structural, optical, morphological, and magnetic and luminescence behaviors. Also, electrochemical analysis was performed to analyze the capacitive nature of the prepared EuVO4 electrodes by using cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance spectroscopy (EIS) techniques. XRD spectrum declares that the synthesized EuVO4 nanorods were highly crystalline in nature with tetragonal structure. FTIR and micro-Raman spectrum reveals the bonding nature of the prepared EuVO4 nanorods. SEM and HRTEM expose the rod-shaped morphology of the prepared EuVO4 nanorods. EDX spectrum justifies the purity of the prepared sample by showing the only presence of Eu, V, and O elements. UV–Vis spectrum shows the broad band from 260 to 280 nm which is due to VO43− absorption. PL spectrum of EuVO4 nanorods illustrate the electronic transitions that occur at 4f6, 5d1 → 4f7, which make an excellent photoluminescence emission in the region of blue (484 nm). From the CV and GCD studies, the maximum specific capacitance values of the EuVO4 nanorods were estimated as 106.9 F g−1 (5 mV s−1) and 146 F g−1 (1 A g−1) and the Columbic efficiency for 5 A g−1 and 6 A g−1 as 94.7% and 94.5%, respectively, which gives hope for the prepared EuVO4 nanorods that can act as perfect electrodes in supercapacitors.

In this study, pristine ZrO2 (600 °C) and Mg (0.02, 0.04, 0.06, 0.08 M)-doped ZrO2 nanoparticles were effectively synthesized at about 10 nm size and achieved complete degradation of methyl violet and methyl blue dyes under UV irradiation. The calcined products were analyzed by XRD, FTIR, UV-DRS, PL, FESEM-EDX, TEM-SAED pattern and XPS techniques. The tetragonal crystal structure of the pristine ZrO2 and Mg (0.02–0.08 M)-doped ZrO2 nanoparticles were affirmed by XRD analysis. The Mg (0.08 M)-doped ZrO2 nanoparticles were approximately in quasi-spherical morphology and high agglomeration was confirmed by FESEM and TEM results. The surface defects and oxygen vacancies were analyzed by PL spectroscopy. The Mg (0.08 M)-doped ZrO2 nanoparticles exhibited enlarged photocatalytic activity with 94% and 90% degradation of methyl violet and methyl blue dyes under UV irradiation.

Reduced graphene oxide (RGO) anchored vanadium pentoxide (V2O5) nanorods have been synthesized by using simple and cost efficacious sol–gel method. The prepared sample was analyzed by different physical and electrochemical techniques such as TG/DTA, XRD, XPS, FTIR, Micro-Raman, FESEM, HRTEM and cyclic voltammetry and galvanostatic charge/discharge. The electrochemical characterization shows that all the curves exhibit quasi-rectangular shape with redox peak, which indicates the pseudocapacitance nature of the V2O5 and RGO/V2O5 electrode materials. V2O5 electrode material exhibits the high specific capacitance (112 F/g) at low scan rate (10 mV/s) due to high surface area. The RGO/V2O5 electrode material exhibits two folds greater specific capacitance values (218.4 F/g at 10 mV/s) than pure V2O5 electrode material. This result clearly indicates the pseudocapacitance nature was enhanced by the RGO nanosheets. The GCD curve also reveals the RGO/V2O5 electrode has good charge/discharge time and superior specific capacitance than bare V2O5 electrode. These excellent electrochemical activities may credit due to RGO nanosheets, which induce large transfer of electrons and also provides high surface sites and short transport path length for the diffusion of electrolyte ions.

Pure ZrO2 and Mn (0.02, 0.04, 0.06, 0.08 M) doped ZrO2 nanoparticles were successfully prepared by chemical precipitation method. The structural, optical, morphological and electronic properties were determined using XRD, UV-DRS, PL, FE-SEM, TEM and XPS techniques. The XRD pattern of pure and Mn doped ZrO2 shows the formation of t-tetragonal phase and shifting of tetragonal phase to monoclinic phase. The energy gap of pure and Mn doped ZrO2 nanoparticles were computed by UV-DRS spectroscopy. The energy gap value of pure and Mn doped ZrO2 nanoparticles decreased from 5.12 to 2.46 eV with increase of manganese concentration. X-ray Photoelectron spectroscopy (XPS) affirmed the presence of Zr4+ and Mn2+ ion in prepared nanoparticles. PL spectra of the pure and Mn doped ZrO2 nanoparticles exhibited oxygen vacancies. The photocatalytic actvity of Mn (0.08 M) doped ZrO2 nanoparticles was successfully sought on photo degradation of Methyl violet and Methylene blue under sunlight irradiation.

This article reports the synthesis of undoped and Ni (1–5%) doped CdSe quantum dots (QDs) through chemical precipitation method. The structure and size of synthesized QDs were studied by X-ray diffraction pattern. The absorption wavelength of both samples were blue shifted with respect to the bulk CdSe phase due to quantum confinement effect. The enhanced photoluminescence was observed for Ni (2%) doped CdSe QDs. The morphology of the undoped and Ni (2%) doped CdSe QDs was studied using FE-TEM analysis.