Precursor preparation of Zn–Al layered double hydroxide by ball milling for enhancing adsorption and photocatalytic decoloration of methyl orange

Abstract

An amorphous photocatalyst was prepared via simple dry milling of Zn basic carbonate (Zn 4 CO 3 (OH) 6 $H 2 O) and Al hydroxide (Al(OH) 3 ) as a precursor of Zn-Al layered double hydroxide (LDH) and the precursor was agitated in water to simply synthesize the Zn-Al LDH for comparison. The adsorption and photocatalytic activity of the Zn-Al LDH and the precursor were studied via the removal of methyl orange (MO) and decoloration of MO under ultraviolet light irradiation in aqueous solution, respectively. The precursor exhibits much higher decoloration efficiency towards MO than the Zn-Al LDH product because of the synergistic effect of the intercalation reaction and its photocatalytic activity. The amorphous precursor could easily incorporate MO molecules to form MO intercalated LDH, allowing easy access of the organic pollutant to the photocatalyst sample, resulting in an obvious improvement in photocatalytic performance. The novel idea to use the precursor sample instead of the synthesized final product may be applied in other fields to increase the required performances.Fig. 5 XRD patterns (left) of LDH, L-MO-LDH (LDH sample with MO adsorption) and P-MO-LDH (the precursor sample with MO adsorption) and the adsorption model (right) of the precursor and LDH. 31470 | RSC Adv., 2017, 7, 31466-31474 This journal is

Exploring the Wet Mechanochemical Synthesis of Mg-Al, Ca-Al, Zn-Al and Cu-Al Layered Double Hydroxides from Oxides, Hydroxides and Basic Carbonates

“…Ageing of the sample resulted in more complete conversion of raw materials to LDH product. Broadening of peaks between 3000 cm −1 and 3700 cm −1 were noted and are due to O-H stretching of hydroxyl groups [31]. Peak formation at approximately 1356 cm 1 and 1620 cm −1 was observed and is likely due to the asymmetric stretching vibrations of CO 3 2− within the interlayer of the LDH [18,30,31].…”

“…Broadening of peaks between 3000 cm −1 and 3700 cm −1 were noted and are due to O-H stretching of hydroxyl groups [31]. Peak formation at approximately 1356 cm 1 and 1620 cm −1 was observed and is likely due to the asymmetric stretching vibrations of CO 3 2− within the interlayer of the LDH [18,30,31]. Peaks below 1000 cm −1 could further be attributed to M-O vibrations (M = Zn, Al) [18,31].…”

Photodegradation Activity of Nitrogen‐rich Graphitic Carbon Nitride Intercalated ZnO\Mg‐Al Layered Double Hydroxide Ternary Nanocomposites on Methylene Blue Dye

“…Layered double hydroxides (LDH), a new class of lamellar metal hydroxide materials, consisting of positively‐charged hydrotalcite‐like layers with carbonate ions and water molecules in the interlayer galleries is a better candidate to be composited with ZnO. Owing to the hexagonal layered structure, LDH possesses a high specific surface area, which can assist fast ion transfer . Dvininov et.al, prepared the SnO 2 /Mg−Al LDH coupling through the thermal treatment which showed good activity for MB dye removal from synthetic wastewaters.…”

Applications of Mechanochemically Prepared Layered Double Hydroxides as Adsorbents and Catalysts: A Mini-Review

“…The excellent anionic organics’ affinity of the precursor could not only be used to produce intercalated LDH, but also adsorb and photocatalytic decolorize anionic dye. Qu et al [56] prepared a Zn-Al LDH precursor photocatalyst by dry milling Zn 4 CO 3 (OH) 6 ·H 2 O and Al(OH) 3 for the adsorption and photocatalytic decoloration of MO. The whole process is shown in Figure 9.…”