Details
| Original language | English |
|---|---|
| Article number | 877 |
| Journal | CATALYSTS |
| Volume | 9 |
| Issue number | 11 |
| Publication status | Published - Nov 2019 |
Abstract
In an endeavor to tackle environmental problems, the photodegradation of microcystin- LR (MC-LR), one of the most common and toxic cyanotoxins, produced by the cyanobacteria blooms, was examined using nanostructured TiO2 photocatalysts (anatase, brookite, anatase- brookite, and C/N/S co-modified anatase-brookite) under UV-A, solar and visible light irradiation. The tailoring of TiO2 properties to hinder the electron-hole recombination and improve MC-LR adsorption on TiO2 surface was achieved by altering the preparation pH value. The highest photocatalytic efficiency was 97% and 99% with degradation rate of 0.002 mmol L-1 min-1 and 0.0007 mmol L-1 min-1 under UV and solar irradiation, respectively, using a bare TiO2 photocatalyst prepared at pH 10 with anatase to brookite ratio of ca. 1:2.5. However, the bare TiO2 samples were hardly active under visible light irradiation (<25%) due to a large band gap. Upon UV, solar and vis irradiation, the complete MC-LR degradation (100%) was obtained in the presence of C/N/S comodified TiO2 with a degradation rate constant of 0.26 min-1, 0.11 min-1 and 0.04 min-1, respectively. It was proposed that the remarkable activity of co-modified TiO2 might originate from its mixedphase composition, mesoporous structure, and non-metal co-modification.
Keywords
- Anatase/brookite, Cyanotoxins, Emerging pollutants, Microcystin-LR, Non-metal co-modification, Photodecomposition
ASJC Scopus subject areas
- Chemical Engineering(all)
- Catalysis
- Chemistry(all)
- Physical and Theoretical Chemistry
Cite this
- Standard
- Harvard
- Apa
- Vancouver
- BibTeX
- RIS
In: CATALYSTS, Vol. 9, No. 11, 877, 11.2019.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - A comparative study of microcystin-LR degradation by UV-a, solar and visible light irradiation using bare and C/N/S-modified titania
AU - Khedr, Tamer M.
AU - El-Sheikh, Said M.
AU - Abdeldayem, Hany M.
AU - Ismail, Adel A.
AU - Kowalska, Ewa
AU - Bahnemann, Detlef W.
N1 - Funding information: This work was supported by the Egyptian Ministry of Higher Education (Cultural Affairs and Missions Sector). A part of this work was also supported by the US–Egypt Joint project Cycle 17 No. 229 and short-term fellowship Cycle 6, Science & Technological Development Fund in Egypt (STDF-STF) under Grant No. 25503.
PY - 2019/11
Y1 - 2019/11
N2 - In an endeavor to tackle environmental problems, the photodegradation of microcystin- LR (MC-LR), one of the most common and toxic cyanotoxins, produced by the cyanobacteria blooms, was examined using nanostructured TiO2 photocatalysts (anatase, brookite, anatase- brookite, and C/N/S co-modified anatase-brookite) under UV-A, solar and visible light irradiation. The tailoring of TiO2 properties to hinder the electron-hole recombination and improve MC-LR adsorption on TiO2 surface was achieved by altering the preparation pH value. The highest photocatalytic efficiency was 97% and 99% with degradation rate of 0.002 mmol L-1 min-1 and 0.0007 mmol L-1 min-1 under UV and solar irradiation, respectively, using a bare TiO2 photocatalyst prepared at pH 10 with anatase to brookite ratio of ca. 1:2.5. However, the bare TiO2 samples were hardly active under visible light irradiation (<25%) due to a large band gap. Upon UV, solar and vis irradiation, the complete MC-LR degradation (100%) was obtained in the presence of C/N/S comodified TiO2 with a degradation rate constant of 0.26 min-1, 0.11 min-1 and 0.04 min-1, respectively. It was proposed that the remarkable activity of co-modified TiO2 might originate from its mixedphase composition, mesoporous structure, and non-metal co-modification.
AB - In an endeavor to tackle environmental problems, the photodegradation of microcystin- LR (MC-LR), one of the most common and toxic cyanotoxins, produced by the cyanobacteria blooms, was examined using nanostructured TiO2 photocatalysts (anatase, brookite, anatase- brookite, and C/N/S co-modified anatase-brookite) under UV-A, solar and visible light irradiation. The tailoring of TiO2 properties to hinder the electron-hole recombination and improve MC-LR adsorption on TiO2 surface was achieved by altering the preparation pH value. The highest photocatalytic efficiency was 97% and 99% with degradation rate of 0.002 mmol L-1 min-1 and 0.0007 mmol L-1 min-1 under UV and solar irradiation, respectively, using a bare TiO2 photocatalyst prepared at pH 10 with anatase to brookite ratio of ca. 1:2.5. However, the bare TiO2 samples were hardly active under visible light irradiation (<25%) due to a large band gap. Upon UV, solar and vis irradiation, the complete MC-LR degradation (100%) was obtained in the presence of C/N/S comodified TiO2 with a degradation rate constant of 0.26 min-1, 0.11 min-1 and 0.04 min-1, respectively. It was proposed that the remarkable activity of co-modified TiO2 might originate from its mixedphase composition, mesoporous structure, and non-metal co-modification.
KW - Anatase/brookite
KW - Cyanotoxins
KW - Emerging pollutants
KW - Microcystin-LR
KW - Non-metal co-modification
KW - Photodecomposition
UR - http://www.scopus.com/inward/record.url?scp=85075060181&partnerID=8YFLogxK
U2 - 10.3390/catal9110877
DO - 10.3390/catal9110877
M3 - Article
AN - SCOPUS:85075060181
VL - 9
JO - CATALYSTS
JF - CATALYSTS
SN - 2073-4344
IS - 11
M1 - 877
ER -