Tetragonal zirconia (t-ZrO2) nanoparticles were synthesized from the zirconium chloride using the co-precipitation technique and characterized by various measurement techniques. FESEM analysis further revealed spherical shaped NPs and HR-TEM analysis determined the size of the particles in the range of 14. 5 nm. The band gap energy was estimated 4. 0 eV. The UV (350 nm) emission was observed from PL spectrum. The photocatalytic degradation of the as-prepared ZrO2 nanoparticles were studied under UV light irradiation using ciprofloxacin (CIP) as a model organic pollutant. Results showed that 50% degradation were achieved within 15 min.

We report here the synthesis of carbon-supported ZrO2 nanoparticles from zirconium oxyphthalocyanine (ZrOPc) and acetylacetonate [Zr (acac)4]. Using thermogravimetric analysis (TGA) coupled with mass spectrometry (MS), we could investigate the thermal decomposition behavior of the chosen precursors.According to those results, we chose the heat treatment temperatures (THT) using partial oxidizing (PO) and reducing (RED) atmosphere. By X-ray diffraction we detected structure and size of the nanoparticles; the size was further confirmed by transmission electron microscopy.ZrO2 formation happens at lower temperature with Zr (acac)4 than with ZrOPc, due to the lower thermal stability and a higher oxygen amount in Zr (acac)4. Using ZrOPc atTHT C900 oC, PO conditions facilitate the crystallite growth and formation of distinct tetragonal ZrO2, while with Zr (acac)4 a distinct tetragonal ZrO2 phase is observed already atTHT C750 oC in both RED and PO conditions. Tuning of ZrO2 nanocrystallite size from 5 to 9 nm by varying the precursor loading is also demonstrated. The chemical state of zirconium was analyzed by X-ray photoelectron spectroscopy, which confirms ZrO2 formation from different synthesis routes.

ZrO2 nanopowder was prepared by the sol-gel auto-combustion method. The product was characterized by X-ray diffraction (XRD), energy dispersive analysis of X-ray (EDX) and scanning electron microscopy (SEM). The average crystalline size of ZrO2 was obtained 62 nm. Also, photocatalytic removal of nitrophenol from aqueous solution by using nanoscale ZrO2 under UV light irradiation was studied. The effect of initial pollution concentrations in 3, 5 and 10 ppm in presence of ZrO2 nanoparticles was studied in photocatalytic degradation process. Nitrophenol was degraded 84, 78 and 66% in the presence of 0.04 g of ZrO2 within 70 minutes.

A novel MCM/ZrO2 nanoparticles modified carbon paste electrode (MZ-CPE) was fabricated and used to study the electro oxidation of epinephrine (EP) and acetaminophen (AC) and their mixtures by electrochemical methods. The modified electrode showed electrocatalytic activity toward EP and AC oxidation with a decrease of the overpotential by 173 mV to a less positive potential for EP at the surface of the MZ-CPE and an increase in peak current at pH 7.0. Differential pulse voltammetry peak currents of EP and AC increased linearly with their concentrations in the ranges of 1.0×10−6–2.5×10−3 and 1.0×10−6–2.0×10−3 M, respectively, and the detection limits for EP and AC were 5.0×10−7 and 4.5×10−7 M, respectively.