Enhanced Photocatalytic Activity of <i>Ficus elastica</i> Mediated Zinc Oxide-Zirconium Dioxide Nanocatalyst at Elevated Calcination Temperature: Physicochemical Study

oleh: Sirajul Haq, Humma Afsar, Israf Ud Din, Pervaiz Ahmad, Mayeen Uddin Khandaker, Hamid Osman, Sultan Alamri, Muhammad Imran Shahzad, Nadia Shahzad, Wajid Rehman, Muhammad Waseem

Format: Article
Diterbitkan: MDPI AG 2021-12-01

Deskripsi

The photocatalytic degradation of Rhodamine 6G dye was achieved using a <i>Ficus elastica</i> (F. elastic) leaf extract mediated zinc oxide-zirconium dioxide nanocatalyst (ZnO-ZrO<sub>2</sub> NC) under stimulated solar light, resulting in a substantial increase in photocatalytic activity at the highest calcination temperature. The crystal phase and crystallite size were determined using an X-ray diffractometer (XRD), and the degree of crystallinity was observed to rise with increasing calcination temperature. Energy dispersive X-ray (EDX) was used to investigate the elemental composition and purity of ZnO-ZrO<sub>2</sub> NC. Scanning electron microscopy (SEM) was used to investigate the surface morphology, and the morphological characteristics were altered when the calcination temperature was varied. For the ZnO-ZrO<sub>2</sub> NC calcined at 100, 300, 600, and 900 °C, the average grain size determined from SEM images is 79.56 nm, 98.78 (2) nm, 54.86 (2) nm, and 67.43 (2) nm, respectively. Using diffuse reflectance spectroscopy (DRS) data, the optical band gap energy was calculated using a Tauc’s plot. The ZnO in ZnO-ZrO<sub>2</sub> NC calcined at 100, 300, 600, and 900 °C had band gap energies of 3.31, 3.36, 3.38, and 3.29 eV. Similarly, ZrO<sub>2</sub> in ZnO-ZrO<sub>2</sub> NC calcined at 100, 300, 600, and 900 °C had band gap energies of 3.96, 3.99, 3.97, and 4.01 eV, respectively. Fourier transform infrared (FTIR) spectroscopy was used to identify the presence of various functional groups. The photocatalytic activity was also examined in relation to calcination temperature, pH, starting concentration, and catalyst dosage. Enhanced photocatalytic activity was observed at pH 11 and 15 ppm initial concentration with a catalyst dose of 25 mg. The photocatalytic activity of the sample calcined at 900 °C was the highest, with 98.94 percent of the dye mineralized in 330 min at a degradation rate of 0.01261/min.