Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Powiadomienia systemowe

Sesja wygasła!

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: rozkład barwnika

Sortuj według:

Ogranicz wyniki do:

Enhancement photocatalytic activity of Mn doped CdS/ZnO nanocomposites for the degradation of methylene blue under solar light irradiation

Sivaranjani Kaliyappan, Sivakumar Santhanam, Dharmaraja Jaganathan

Advances in Materials Science

2022

Vol. 22, nr 2(72)

28--48

In this study, Mn doped CdS/ZnO nanocomposites synthesized by co-precipitation method and its photocatalytic activity was tested using methylene blue under solar light irradiation. The prepared hybrid nanocomposites are characterized by using different physicochemical techniques including XRD, FESEM, EDX, TEM, UV-vis DRS and PL analysis. From the XRD analysis, Mn doped ZnO/CdS nanocomposite diffraction peaks only reflect the binary crystalline structures of ZnO and CdS. However, there is no characteristic peak of Mn is found that may be because of low content of Mn doped on ZnO/CdS. But Mn (2.9 wt%) was detected in the Mn doped ZnO/CdS nanocomposite, which was measured by EDX analysis. The FESEM and TEM results exhibit the surface particle of Mn doped ZnO/CdS nanocomposite which have spherical nature and confirmed the formation of Mn doped ZnO/CdS nanocomposites. The photocatalytic degradation results have revealed that the Mn doped CdS/ZnO nanocomposites exhibit admirable activity toward the photocatalytic degradation of the MB. The reason for excellent photocatalytic activity of Mn doped CdS/ZnO nanocomposites indicates the absorbance band shifted to red region and reduction of recombination of photogenerated electron-hole, which is in good agreement with UV-visible DRS analysis and PL study results. The fitted kinetic plots showed a pseudo-first-order reaction model and the appropriate rate constants were found to be 0.0068 min−1, 0.00846 min−1, and 0.0188 min−1, for ZnO, 25 % CdS/ZnO, and 0.8 mol% Mn doped CdS/ZnO nanocomposites, respectively. The maximum photocatalytic activity was achieved by 0.8 mol% Mn doped CdS/ZnO nanocomposites with a 95% degradation efficiency of MB. Hydroxyl and superoxide radicals, having a vital role in the degradation of MB, confirmed scavenging experiments. In addition, the recycling tests displays that the Mn doped CdS/ZnO nanocomposites have shown good stability and long durability. The enhanced photodegradation activity of Mn doped CdS/ZnO nanocomposites indicates the potential of the nanocomposite for the treatment of organic pollutants from the textile wastewater.

Decomposition of Azo Dye C.I. Direct Yellow 86 by the Fenton Process in the Presence of Nanoparticles of Iron Oxides

Kos L, Sójka-Ledakowicz J, Michalska K, Perkowski J

Fibres & Textiles in Eastern Europe

2014

Vol. 22, no. 5 (107)

114--120

The aim of the study was to determine the efficiency of decomposition of azo dye C.I. Direct Yellow 86 by the Fenton method in the presence of nanoparticles of iron oxides and to compare it with the classical Fenton method. Water solutions of the dye were subjected to the classical purification method with the application of ferrous sulfate and – for comparison – to a process in which iron (II,III) oxide nanopowder was added to the ferrous sulfate. Analysis of the effect of the ferrous sulfate, iron (II,III) oxide nanopowder, hydrogen peroxide and the pH of the solution on the treatment efficiency showed that the process was optimised. The use of iron oxide nanopowder increased the efficiency of dye decomposition.

Celem badań było określenie efektywności rozkładu barwnika azowego C.I. Direct Yellow 86 metodą Fentona przy udziale nanocząstek tlenków żelaza i porównanie jej z efktywnością klasycznej metody Fentona. Roztwory wodne barwnika oczyszczano metodą klasyczną stosując siarczan żelazawy oraz metodą zmodyfikowaną stosując siarczan żelazawy z dodatkiem nanocząstek tlenków żelaza (II,III). Dokonano optymalizacji procesu oczyszczania badając wpływ dawek siarczanu żelazawego i nanocząstek tlenków żelaza (II,III), dawki nadtlenku wodoru oraz pH roztworu na efektywność obróbki. Zastosowanie dodatku nanocząstek tlenków żelaza w zmodyfikowanym procesie klasycznym przebiegającym z udziałem siarczanu żelazawego zwiększało wydajność rozkładu barwnika.