Sunlight-Active BiOI Photocatalyst as an Efficient Adsorbent for the Removal of Organic Dyes and Antibiotics from Aqueous Solutions

Abstract

A bismuth oxyiodide (BiOI) photocatalyst with excellent sunlight-driven performance was synthesized by a solvothermal route without the addition of surfactants or capping agents. The prepared photocatalyst exhibited a tetragonal phase with an energy band gap of 2.15 eV. The efficiency of the photocatalyst was elucidated by monitoring the photodegradation of organic dyes and antibiotics. The BiOI photocatalyst provided a 95% removal of norfloxacin (NOR) antibiotics under visible light illumination. Interestingly, the complete removal of Rhodamine B (RhB) dye was achieved after 80 min of natural sunlight irradiation. The photodegradation reaction followed the first-order reaction. Both photo-generated holes and electrons play vital roles in the photodegradation of the pollutant. The BiOI photocatalyst remains stable and still shows a high efficiency even after the fifth run. This confirms the great cycling ability and high structural stability of the photocatalyst. The prepared BiOI catalyst, with a high surface area of 118 m2 g−1, can act as an excellent adsorbent as well. The synergistic effect based on both adsorption and photocatalysis is a key factor in achieving a very high removal efficiency. The photoactivity under sunlight is higher than that observed under visible light, supporting the practical use of the BiOI photocatalyst for the removal of organic pollutants in wastewater through the utilization of abundant solar energy.

Sonochemically Synthesized Bismuth Oxyiodide Nanocrystal for Wastewater Remediation through Visible‐Light Photocatalysis

“…The calculated CB and VB edge potentials (versus NHE) for the B‐WP samples are found to be 0.30 and 3.06 V, respectively. [ 17 ]…”

“…The calculated CB and VB edge potentials (versus NHE) for the B-WP samples are found to be 0.30 and 3.06 V, respectively. [17] From the scavenger test it is confirmed that the photogenerated holes, hydroxyl radicals, and electrons are the primary radicals performing in the photocatalytic activity. Now, the redox potential for the formation of H 2 O 2 from O 2 lies at 0.69 V (NHE), whereas the CB edge of the sample is at 0.30 V. Since the H 2 O 2 /O 2 redox potential is at a more positive level tan the CB…”

Ag-Modified ZnO for Degradation of Oxytetracycline Antibiotic and Reactive Red Azo Dye

“…Even a low concentration of the azo dye in water is visible and undesirable [ 4 , 5 , 6 ]. Therefore, searching for a cost-effective technology for the treatment of water containing this toxic dye is needed [ 7 , 8 , 9 , 10 , 11 ]. Oxytetracycline (OTC) is a typical drug used for the treatment of bacterial-infectious diseases [ 12 , 13 ].…”

“…However, this photocatalyst is active only under UV light (5% of natural sunlight) [ 22 , 23 , 24 ]. Interestingly, the search for new photocatalysts with high performance under an economical solar energy is a promising research direction [ 9 , 10 , 11 , 12 , 13 , 14 , 19 ].…”

Selective Oxofunctionalization of Cyclohexane and Benzyl Alcohol over BiOI/TiO2 Heterojunction

“…Traditionally, photocatalysis has been employed in wastewater treatment [8], destruction of microorganisms [9], and degradation of toxins [10], dyes [11], surfactants [12], fatty acids [13], antibiotics [14,15] and organic pollutants [16,17]. Due to their high reactivity, photocatalytic systems based on semiconductors are non-specific and have been rarely applied in the selective conversion of organic compounds [18].…”