Metal Oxide Photocatalysts for Transformation of Nitroaromatic Compounds

Abstract

Environmental pollution is an important global challenge of this time. The increasing scarcity of energy resources has urged us to seek alternative sources and methods of renewable energy in order to address environmental concerns. Solar energy offers a huge potential for usage as a source of energy for environmental remediation. Research interest in metal oxide semiconductors such as TiO2, ZrO2, and ZnO has attracted the attention of scientists in recent years because of their superb oxidation-reduction reaction, higher surface area, and greater light absorption capability. In this research project, we have focused on the synthesis of metal-doped, core-shell, binary and ternary heterostructures of TiO2, ZnO and ZrO2, to utilize as photocatalysts for nitroaromatic compounds’ transformation. Copper-doped TiO2 (0.1, 0.25, and 0.5 % Cu-TiO2) photocatalyst was prepared using the sol gel method. The structural, morphological, and optical analysis confirmed the successful doping of Cu within the TiO2 lattice. The photocatalytic efficiency of the prepared Cu-TiO2 was assessed by the degradation of nitrobenzene (NB) for the first time. 0.25 % Cu-TiO2 demonstrated excellent photodegradation activity of 98.6% as compared to TiO2 and other Cu TiO2 (0.1, and 0.5 %) in a time span of 180 min. These findings exhibited the potential of 0.25% Cu-TiO2 photocatalyst for the efficient degradation of NB into harmless substances such as H2O and CO2. The Zinc oxide/copper oxide binary heterojunctions were prepared via a facile sono coprecipitation method with different concentrations of CuO (ZnO: CuO (1:0, 1:1, and 1:2)), denoted as Z, ZC-1:1, and ZC-1:2, and its application was evaluated towards photocatalytic reduction of 2,4-dinitrophenol (2,4-DNP), and 2,4,6-trinitrophenol (2,4,6-TNP) to their respective aminophenols. Among the prepared materials, the ZC-1:1 exhibits much superior

Environmental pollution is an important global challenge of this time. The increasing scarcity of energy resources has urged us to seek alternative sources and methods of renewable energy in order to address environmental concerns. Solar energy offers a huge potential for usage as a source of energy for environmental remediation. Research interest in metal oxide semiconductors such as TiO2, ZrO2, and ZnO has attracted the attention of scientists in recent years because of their superb oxidation-reduction reaction, higher surface area, and greater light absorption capability. In this research project, we have focused on the synthesis of metal-doped, core-shell, binary and ternary heterostructures of TiO2, ZnO and ZrO2, to utilize as photocatalysts for nitroaromatic compounds’ transformation. Copper-doped TiO2 (0.1, 0.25, and 0.5 % Cu-TiO2) photocatalyst was prepared using the sol gel method. The structural, morphological, and optical analysis confirmed the successful doping of Cu within the TiO2 lattice. The photocatalytic efficiency of the prepared Cu-TiO2 was assessed by the degradation of nitrobenzene (NB) for the first time. 0.25 % Cu-TiO2 demonstrated excellent photodegradation activity of 98.6% as compared to TiO2 and other Cu TiO2 (0.1, and 0.5 %) in a time span of 180 min. These findings exhibited the potential of 0.25% Cu-TiO2 photocatalyst for the efficient degradation of NB into harmless substances such as H2O and CO2. The Zinc oxide/copper oxide binary heterojunctions were prepared via a facile sono coprecipitation method with different concentrations of CuO (ZnO: CuO (1:0, 1:1, and 1:2)), denoted as Z, ZC-1:1, and ZC-1:2, and its application was evaluated towards photocatalytic reduction of 2,4-dinitrophenol (2,4-DNP), and 2,4,6-trinitrophenol (2,4,6-TNP) to their respective aminophenols. Among the prepared materials, the ZC-1:1 exhibits much superior