Photocatalytic degradation of Congo red dye using Fe-doped TiO2 nanocatalysts

Abstract

Fe-doped TiO2 (2, 5, 10, 15 and 20% wt. of Fe) photocatalysts have been synthesized by sol-gel method using titanium aquacomplex precursor. The structure and morphology have been characterized by XRD, BET, SEM, and EDS analyses, Mossbauer and IR spectroscopies. XRD analysis confirmed the anatase structure. The introduction of ferric ions into the titania structure causes its amorphization. The crystallite sizes of obtained samples are around 3 nm. Fe-doped TiO2 samples possess mesoporous structure and high specific surface area (from 274 m2g-1 for 5Fe-TiO2 to 416.4 m2g-1 for 20Fe-TiO2). Mossbauer spectroscopy data confirms the incorporation of Fe3+ ions in the anatase structure. Photocatalytic degradation of Congo red dye using Fe-doped TiO2 photocatalysts was studied under the UV-A light. Optimized conditions for photocatalytic degradation of CR in the presence of hydrogen peroxide are obtained. It was found that the 2Fe-TiO2 sample in the presence of 20 mM H2O2 solution showed highest efficiency in dye photodegradation (99.4%) under UV-A light. The photodegradation kinetics was analyzed using a smartphone and fits well with first-order kinetics model.

Structural, morphological and photocatalytic properties of TiO2 obtained by thermolytic decomposition of the [Ti(OH2)6]3+•3Cl¯ aquacomplex

“…In this work, the photodegradation of Congo Red in an aqueous solution using rutile TiO2 synthesized by thermolytic decomposition of a titanium aquacomplex precursor solution [Ti(OH2)6] 3+ •3Cl ¯ has been studied. LT-TiO2 CR (5 mg/L), H2O2 (10 mM) under UV irradiation (30 min) 99.9 [1] TiO2/SA CR (40 mg/L), H2O2 (20 mM) under visible light irradiation (210 min) 100 [32] Ni-TiO2 CR (10 mg/L) under UV irradiation (180 min) 92.31 [2] 2% Fe 3+ -doped TiO2 CR (5 mg/L), H2O2 (20 mM) under UV irradiation (30 min) 99.4 [33] Mg-TiO2-P25/PMS CR (2.5*10 -5 M) under visible light irradiation (120 min) 95 [34] TiO2 doped cobalt ferrite CR (10 mg/L) under visible light irradiation (120 min) 97 [35] TiO2 CR (5 mg/L), H2O2 (5 mM) under UV irradiation (10 min) 100 This work…”

Doping TiO2 with Fe from iron rusty waste for enhancing its activity under visible light in the Congo red dye photodegradation

“…The Congo red dye contamination adheres to the ecosystem and human health, since it is able to destroy biotics as well as causes nausea, vomiting, and diarrhea [19][20][21][22], event induces cancer for humans. Various methods have been reported for diminishing the dye such as adsorption [19], biodegradation [20], ozonation [21], photo-Fenton [22,23], and photocatalytic degradation over Fe-doped TiO 2 [24]. However, photodegradation over TiO 2 doped with Fe from the iron rusty waste has not been explored yet.…”

Флуоресцентне Кількісне Визначення Адсорбції Пептидів На Діоксиді Титану

“…Typically, the sorption of organic compounds onto TiO2 is measured using a spectrophotometric method [7]. It is applicable to compounds with distinct light absorption properties like dyes Congo red [8], Methylene blue [9].…”