Fabrication of 3D Gelatin Hydrogel Nanocomposite Impregnated Co-Doped SnO<sub>2</sub> Nanomaterial for the Catalytic Reduction of Environmental Pollutants

oleh: Hadi M. Marwani, Shahid Ahmad, Mohammed M. Rahman

Format: Article
Diterbitkan: MDPI AG 2022-07-01

Deskripsi

In the catalytic reduction of various environment pollutants, cobalt-doped tin oxide, i.e., Co-SnO<sub>2</sub> intercalated gelatin (GL) hydrogel nanocomposite was prepared via direct mixing of Co-SnO<sub>2</sub> doped with GL. Then, it was crosslinked internally using formaldehyde within a viscous solution of gelatin polymer, which led to the formation of GL/Co-SnO<sub>2</sub> hydrogel nanocomposite. GL/Co-SnO<sub>2</sub> hydrogel nanocomposite was fully characterized by using field-emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), and attenuated total reflection–Fourier transform infrared spectroscopy (ATR-FTIR). The FESEM images indicate that the Co-SnO<sub>2</sub> composite has a spherical structure on the GL matrix while EDX elucidates the elemental composition of each atom in the crosslinked GL/Co-SnO<sub>2</sub> hydrogel nanocomposite. The GL/Co-SnO<sub>2</sub> nanocomposite was checked for the reduction of various pollutants, including 2-nitro-phenol (2-NP), 2,6-dinitro-phenol (2,6-DNP), 4-nitro-phenol (4-NP), Congo red (CR), and methyl orange (MO) dyes with a strong sodium borohydride (NaBH<sub>4</sub>) reducing agent. The GL/Co-SnO<sub>2</sub> nanocomposite synergistically reduced the MO in the presence of the reducing agent with greater reduction rate of 1.036 min<sup>−1</sup> compared to other dyes. The reduction condition was optimized by changing various parameters, such as the catalyst amount, dye concentration, and the NaBH<sub>4</sub> amount. Moreover, the GL/Co-SnO<sub>2</sub> nanocomposite catalyst can be easily recovered, is recyclable, and revealed minimal loss of nanomaterials.