Abstract:
Continuous discharge of textile wastes such as dyes into the water bodies deteriorates the
quality of water. Therefore, the removal of these materials from the wastewater should be a
priority due to their carcinogenic properties, which pose a health hazard to both human beings
and aquatic life. The use of advanced oxidation processes (AOPs) for example heterogeneous
photocatalysis has been broadly studied due to their efficacy in the removal of such organic
contaminants. Engineering of the bandgap via doping is among the strategies for enhancing the
photocatalytic performance of the nanomaterials and the fact that bismuth oxy-halide (BiOM,
(M = Br, Cl, I)) can be modified to form solid solutions make them suitable candidates for this
study. This dissertation describes the synthesis, characterization, and applicability of BiOBrmI(1-
m)solid solutions materials. The materials were prepared through a simple hydrothermal method
at 160 °C. The applicability of the prepared materials was examined through the photocatalytic
degradation of Methylene blue (MB) dye under solar and UV-light irradiation.
The particle size and morphology of the synthesized solid solutions were obtained by scanning
electron microscopy (SEM) and transmission electron microscope (TEM), respectively. X-ray
diffractometer (XRD) patterns revealed the structural features of the prepared materials. The
optical properties such as absorption edge, energy bandgap, and photodegradation studies were
obtained by the UV-Vis spectrophotometer. The Brunauer-Emmett-Teller (BET) was applied
to determine the surface area and the pore size distribution of the materials. Vibrational modes
of the materials were determined using Raman spectroscopy. From SEM analysis, BiOBr
displayed ultrathin plates-like structures that are large and thick with variable dimensions.
BiOBr0.2I0.8, BiOBr0.4I0.6, BiOBr0.6I0.4, and BiOBr0.8I0.2 showed flake-like structures as the
morphology, whereas BiOI displayed flower-like structures as the morphology. The formation
of flakes and flower-like structure is due to the microplates undergoing self-assembly to form
3-dimensional structures. Energy-dispersive X-ray spectroscopy (EDAX) study confirmed the
existence of Bi, O, Br, and I. The XRD peaks corresponding to (102) planes shifted to the lower
diffraction angle with an increase in the composition of iodide.
From the optical properties analysis, the bandgap was tailored from 2.59 to 1.96 eV via doping.
The BET surface area of BiOBr, BiOBr0.6I0.4, and BiOI was found to be 0.517, 3.249, and 1.890
xvii
m2
/g, respectively. The photodegradation of MB was monitored through color and COD
reduction. After 3 h of solar and UV irradiation, the degradation efficiencies over BiOBr0.6I0.4
were 99 and 88%, respectively. The stability of the BiOBrmI(1-m) solid solution was revealed
by the reusability of BiOBr0.6I0.4 for 5 cycles with degradation percentage decreasing to 82%
after the 5
th cycle. From the scavenging experiment, it was confirmed that superoxide (O2
•
⁻)
and photogenerated holes (h+
) were liable for the degradation of MB. From the study, it can be
established that bismuth oxyhalide solid solution is an effective material in the treatment of MB
under irradiation from solar and UV-light and thus holds huge promise in environmental
remediation.
Ouko, G (2024). Bismuth Oxy-halide (BiOBrmI(1-m)) solid solutions for the photodegradation of methylene blue dye under solar and UV-light irradiation.. Afribary. Retrieved from https://afribary.com/works/bismuth-oxy-halide-biobrmi-1-m-solid-solutions-for-the-photodegradation-of-methylene-blue-dye-under-solar-and-uv-light-irradiation
Ouko, Gembo "Bismuth Oxy-halide (BiOBrmI(1-m)) solid solutions for the photodegradation of methylene blue dye under solar and UV-light irradiation." Afribary. Afribary, 30 Mar. 2024, https://afribary.com/works/bismuth-oxy-halide-biobrmi-1-m-solid-solutions-for-the-photodegradation-of-methylene-blue-dye-under-solar-and-uv-light-irradiation. Accessed 08 Sep. 2024.
Ouko, Gembo . "Bismuth Oxy-halide (BiOBrmI(1-m)) solid solutions for the photodegradation of methylene blue dye under solar and UV-light irradiation.". Afribary, Afribary, 30 Mar. 2024. Web. 08 Sep. 2024. < https://afribary.com/works/bismuth-oxy-halide-biobrmi-1-m-solid-solutions-for-the-photodegradation-of-methylene-blue-dye-under-solar-and-uv-light-irradiation >.
Ouko, Gembo . "Bismuth Oxy-halide (BiOBrmI(1-m)) solid solutions for the photodegradation of methylene blue dye under solar and UV-light irradiation." Afribary (2024). Accessed September 08, 2024. https://afribary.com/works/bismuth-oxy-halide-biobrmi-1-m-solid-solutions-for-the-photodegradation-of-methylene-blue-dye-under-solar-and-uv-light-irradiation