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Polyoxometalate Intercalated MgAl-Layered Double Hydroxide for Degradation of Malachite Green

Hanifah Yulizah, Mohadi Risfidian, Mardiyanto, Lesbani Aldes

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 2

109--119

EN

Improving the selectivity of photocatalysis of LDH pristine (MgAl-LDH) and LDH composite (MgAl-SiW12O40] and MgAl-[PW12O40]) was synthesized and used for degraded malachite green (MG). The effects of the amount of catalyst, pH value, and reaction times on degradation performance were discussed. MG degraded better composites than LDH pristine. The results indicated that MgAl-LDH was successfully synthesized by showing the peak diffractions at angles 10.39°(003), 20.17°(006), and 34.8°(009). Both kinds of attained MgAl-[SiW12O40] and MgAl-[PW12O40] had the typical structure of LDH that proved by appeared diffraction at 2θ angles 7.73°, 28.6°, 35.6° for MgAl-[PW12O40] and at 2θ angles 8.61°, 24.27°, 34.96° and 66.34° for MgAl-[SiW12O40]. The FTIR result indicates materials used for fifth regeneration, which confirmed the LDH composite structure. The photodegradation activity of MG for pristine MgAl LDH (56.1%), composites MgAl-Pw (84.6%) and MgAl-Si (87.8%), respectively. The successful ability of photodegradation process by the percentage of degradation on material LDH-polyoxometalate composite showed the increasing of photodegradation catalytic and the regeneration ability of LDH pristine.

2

Polyoxometalate Intercalated Layered Double Hydroxide for Degradation of Procion Red

Hanifah Yulizah, Mohadi Risfidian, Mardiyanto, Lesbani Aldes

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 6

109--116

EN

The synthesis and characterization of layered double hydroxide (LDH) and intercalated polyoxometalate were presented.. The growth of polyoxometalate on Ni/Mg layered double hydroxide for degradation procion red (PR) was reported. The degradation parameters and organic dye removal efficiency of Zn/Mg-LDH and both composite LDH-polyoxometalate were determined by considering factors such as pH of dye solution, catalyst dosage, and time as variables of degradation. X-Ray, FTIR, and SEM spectroscopy confirmed the layered double hydroxide structure. XRD and FTIR analysis confirmed the single-phase of the as-made and polyoxometalate intercalated LDH. SEM images show the formation of aggregates of small various sizes. The catalytic activity of the material was evaluated in the degradation of PR as a model pollutant. The result showed that MgAl-SiW12O40 has a good degradation capacity for PR as compared to MgAl-PW12O40, ZnAl-SiW12O40, and ZnAl-PW12O40. The result shows that the LDH composite presents stability and has good photocatalytic activities toward the reduction of methylene blue. The materials utilized for the fifth regeneration are indicated by the FTIR results, which verified the LDH composite structure. The photodegradation process of procion red for immaculate ZnAl-LDH, MgAl-LDH, ZnAl-[PW12O40], ZnAl-[SiW12O40], MgAl-[PW12O40], MgAl-[SiW12O40] amounted to 68%, 70%, 56%, 79%, 74%, and 80%, respectively. The capacity of LDH-polyoxometalate composite material to successfully photodegrade, as measured by the percentage of degradation, revealed an increase in photodegradation catalysis and the ability of LDH to regenerate.

3

Soft Ion Divalent Metals toward Adsorption on Zn/Al-POM Layered Double Hydroxide

Silaen Luna, Elfita, Mohadi Risfidian, Normah, Juleanti Novie, Palapa Neza Rahayu, Lesbani Aldes

Journal of Ecological Engineering

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2021

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Vol. 22, nr 10

109--120

EN

Development of Zn/Al layered double hydroxide by intercalation using polyoxometalate (POM) K4 [α-SiW12O40] to Zn/Al-POM was investigated. The success of the modification is evidenced by the XRD, FT-IR, and BET characterization data. XRD characterization showed an increase in the interlayer distance from 8.59 Å in Zn/Al LDHs to 10.26 Å in Zn/Al-POM. This success is also supported by the FT-IR data with the appearance of vibrations around 779–979 cm-1 which indicates the vibration of the polyoxometalate compound in Zn/Al-POM. Other supporting data in the form of BET also prove an increase in surface area from 1.968 m2/g in Zn/Al LDHs to 14.042 m2/g Zn/Al-POM. The ability of Zn/Al-POM as an adsorbent is proven through several parameters such as kinetics, isotherm, thermodynamics, and regeneration for Cd2+, Pb2+, Ni2+, and Co2+. Adsorption kinetics showed that Zn/Al-POM was more likely to follow the pseudo-second-order adsorption kinetics model for Cd2+, Pb2+, Ni2+, and Co2+. The results of determining the adsorption isotherm parameters of Zn/Al-POM tend to follow the Freundlich isotherm model with a maximum adsorption capacity of 74.13 mg/g on Pb2+. The regeneration process showed that Zn/Al-POM was more resistant than Zn/Al LDHs up to 3 cycles. It was proven that Zn/Al-POM was able to survive in the last cycle up to 69.19% on Ni2+.

4

Synthesis, Spectral Characteristics and Antitumor Activity of Tungstosilicic Polyoxometalate Containing 5-Fluorouracil

Feng C. G., Wang S. S., Liu X.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 12

2079-2087

EN

A novel polyoxometalate com pound with 5-fluorouracil C4H4FN2O2H3SiW12O40ź12H2O (FSW) was synthesized and its structure was analyzed using IR spectra, X-ray powder diffraction (XRD), 183W NMR and TG. IR spectra and XRD indicate that FSW has a Keggin structure of heteropolyanion with a ring structure of 5-fluorouracil as expected. It was found by the analysis of the 183W NMR spectra that the W atoms of FSW remain in the same chemical environment. The results of TG show that the compound has two weight-losing steps with certain degree of thermal stability. The present study uses 5-fluorouracil as the positive control group in the cytotoxicity tests of FSW on human renal embryonic cell HEK293 and the antitumor activity tests in cervical cancer cell Hela using the methyl thiazolyl tetrazolium method. The results obtained show that the therapeutic index of the new polyoxometalate compound is 0.75, higher than that of 5-fluoro-uracil.

5

Hydrothermal Synthesis, Structure Characterization of a New Mixed Mo/V Metal-Oxygen Cluster Compound: [Co(phen)3]2[HPMoV4 MoVI4V IV6 M2O44]×4H2O, (M = 0.78MoV + 0.22V IV)

Sun Y. H., Li X. P., Sun D. H., Niu L., Xu J. Q.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 9

1567-1575

EN

A new polyoxometalat[Co(phen)3]2[HPMoV4 MoVI4V IV6 M2O44]×4H2O, (M = 0.78MoV + 0.22V IV)e 1 was hy dro ther mally syn the sized and char ac ter ized by IR, el e men tal anal y ses, X-ray pho to elec tron spec trum, ESR and sin gle crys tal X-ray dif frac tion. The ti tle com - pound is in the triclinic space group P1 with a = 12.0953(7) A, b = 14.0182(6) A, c = 14.6468(7) A, V = 2402.55(18) A3, a = 105.134(2), b = 91.841(3), g = 91.401(2), Z = 1, and R1 (wR2) = 0.0617 (0.1701). The compound was prepared from tetra-capped pseudo-Keggin with phosphorus-centered polyoxoanions [PMo8V6M2O44]5-, [Co(phen)3]2+ cations and linked through hydrogen bonds and p-p stacking inte action into three-dimensional supramolecular framework. A study of the magnetic properties of 1 demonstrates that it exhib its antiferromagnetic coupling interactions.