New Approach for Designing Zinc Oxide Nanohybrids to Be Effective Photocatalysts for Water Purification in Sunlight

Abstract

Water pollution and deficient energy are the main challenges for the scientific society across the world. In this trend, new approaches include designing zinc oxide nanohybrids to be very active in sunlight. In this line, organic and magnetic species intercalate among the nanolayers of Al/Zn to build inorganic-magnetic-organic nanohybrid structures. A series of nanolayered and nanohybrid structures have been prepared through intercalating very fine particles of cobalt iron oxide nanocomposites and long chains of organic fatty acids such as n-capric acid and stearic acid inside the nanolayered structures of Al/Zn. By thermal treatment, zinc oxide nanohybrids have been prepared and used for purifying water from colored pollutants using solar energy. The optical measurements have shown that the nanohybrid structure of zinc oxide leads to a clear reduction of band gap energy from 3.30 eV to 2.60 eV to be effective in sunlight. In this line, a complete removal of the colored pollutants (naphthol green B) was achieved after ten minutes in the presence of zinc oxide nanohybrid and sunlight. Finally, this new approach for designing photoactive nanohybrids leads to positive results for facing the energy- and water-related problems through using renewable and non-polluting energy for purifying water.

Nanolayered Structures and Nanohybrids Based on a Ternary System Co/Ti/Zn for Production of Photo-Active Nanocomposites and Purification of Water Using Light

“…The FT-IR data were summarized in Table 1 . For Co/Zn/Ti LDH, the stretching mode of the hydroxyl groups was observed at 3392 cm −1 , agreeing with the reported results for the conventional LDHs [ 1 , 3 ]. The bending mode band of water molecules was observed at 1623 cm −1 .…”

“…Photocatalytic degradation is one of the most familiar processes belonging to these techniques. Many researchers used photocatalytic reactions for removing pollutants [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ]. In these studies, the researchers tried to prepare and design effective optical materials because the performance of the photocatalytic processes depends mainly on the structure of the optical materials.…”

“…Among the different kinds of materials, nanolayered structures based on layered double hydroxides (LDHs) have many advantages for preparing optical active materials. LDHs consist of several nanolayers connecting through pillars with a large interlayered space [ 3 , 4 , 5 ]. These nanolayers have a cationic nature because they contain different metals with different valences such as di-, tri-, and tetra-valent metals.…”

“…These nanolayers have a cationic nature because they contain different metals with different valences such as di-, tri-, and tetra-valent metals. The presence of the different valences creates a cationic nature for the nanolayers [ 3 , 8 , 9 ]. The pillars have an anionic nature to neutralize the cationic nature of the nanolayers.…”

“…Depending on the nature and the size of the anionic pillars, the internal spacing among the nanolayers can be controlled and changed to appear as a large spectrum of known or unknown properties. By using organic pillars, different kinds of organic–inorganic nanohybrids can be formed to produce an almost unlimited set of new compounds [ 3 , 4 , 5 ].…”