Solar Light Irradiation Research Articles

Establishing Z-scheme Bi2WO6/g-C3N4 interfaces toward efficient photocatalytic performance of NOx under visible light

NOx gas is released from automobile emissions and fossil fuel combustion. The photocatalytic method was applied to address environmental issues, notably NOx air pollution because of environmentally friendly, low cost, and utilized solar light irradiation. In this work, a Z-scheme Bi2WO6/g-C3N4 heterojunction photocatalyst was successfully synthesized by a hydrothermal method at 180 °C for 12 h. Combining g-C3N4 with Bi2WO6 promoted two oxidation (over Bi2WO6) and reduction (over g-C3N4) sites, enhancing the photocatalytic activity of the g-C3N4 single-component system. The sample contains 20 wt% of Bi2WO6, becoming the best excellent photocatalytic activity at approximately 43.45% in 30 minutes of visible light irradiation. In addition, the photogenerated electron (e−) and hole (h+) were determined as primary agents. The high stability of Bi2WO6/g-C3N4 photocatalysts was demonstrated by little change in photocatalytic performance over five cycles of photocatalytic measurements. The NOx removal mechanism and the intermediate generation were proposed to understand the reaction process better.

Fabrication and characterization of solar active BN coupled with ZnO composite catalysts for efficient photocatalytic detoxification of methyl orange dye under solar and visible light irradiation

In this paper, pure ZnO and hexagonal boron nitride (BN) loaded ZnO nanorods were synthesized via a simple hydrothermal method. XRD analysis revealed good crystallinity and hexagonal wurtzite structure of the synthesized materials. FE-SEM images showed the nanorod-like structure of the ZnO material. The UV-DRS spectra showed a decrease in the optical bandgap of BN-ZnO due to the loading of BN. The outcomes from the EIS analysis indicated that the 3% BN-ZnO photocatalyst exhibited the most favorable recombination rate for electron-hole pairs and the least resistance to electron transfer. Photocatalytic evaluation for methyl orange (MO) detoxification under sunlight and visible light illumination revealed that 3% BN-ZnO showed the highest activity, and kinetic studies showed pseudo-first-order degradation. Moreover, the sunlight process outperforms than visible light process, which can be attributed to the ≈ 4% UV radiation available in the solar spectrum. TOC studies confirmed the mineralization of the MO dye. Trapping experiments using various quenchers show that superoxide radicals (O2•−) anion play a major role in the degradation process. Finally, we proposed a plausible photocatalytic mechanism based on our findings.

A Brief Review on Solar Light Assisted Photocatalytic Degradation of Dyes using Double/Layered Perovskites

Abstract:: During the past few decades, great efforts have been devoted to developing non-toxic, low-cost, green and studied photocatalysts for the degradation of toxic dyes from surface water with the aid of sustainable, plentiful, and renewable solar light irradiation. Perovskite oxides with a wide range of applications, including photocatalytic water decontamination possess unique properties that make them suitable for performing efficiently in visible spectrum and facilitate catalytic reactions. This mini-review specifically specializes in double/layered perovskites and their associated materials and summarizes the recent improvement of double/layered perovskite photocatalysts and their packages in the degradation of organic dyes.

Performance of a Solar-Driven Photocatalytic Membrane Reactor for Municipal Wastewater Treatment

The increasing demand for efficient wastewater treatment technologies, driven by global population growth and industrialisation, highlights the necessity for advanced, reliable solutions. This study investigated the efficacy of a slurry photocatalytic membrane reactor (PMR) for the advanced removal of organic pollutants, quantified via chemical oxygen demand (COD), under natural and simulated solar light irradiation. Employing two variants of iron-doped titania as photocatalysts and a polysulfone-based polymeric membrane for the separation process, the investigation showcased COD removal efficiencies ranging from 66–85% under simulated solar light to 52–81% under natural sunlight over a 7 h irradiation period. The overall PMR system demonstrated COD removal efficiencies of 84–95%. The results confirmed the enhanced photocatalytic activity afforded by iron doping and establish solar-powered slurry PMRs as an effective, low-energy, and environmentally friendly alternative for the advanced treatment of municipal wastewater, with the research providing valuable insights into sustainable water management practices.

Preparation, characterization of green synthesis FeO nanoparticles and their photocatalytic activity towards Basic Fuschin dye

In the current study, a green and facile route for the synthesis of iron oxide nanoparticles (FeO-NPs) was adopted. The FeO-NPs were fabricated via a single step green route using aqueous leaf extract of Aegle marmelos (A. marmelos) as capping/reducing and stabilizing agents.The active phytochemicals present in the A. marmelos extract was reduced and stabilized the metal ions to FeO-NPs. This product was analyzed by FTIR spectral studies. Magnetic FeO-NPs surface morphology and particles sizes were determined by HRTEM to reveals spherical shapes with average diameter 18.78 nm. The instrumentally confirmed FeO-NPs were determining the antimicrobial activity against the pathogenic strains of the bacteria Streptococcus Sp and the fungus Candida Sp. The results of the microbial investigation show that when the concentration of synthesized FeO-NPs increase with the increases the activity. The antioxidant properties of synthesized FeO-NPs were evaluated by the DPPH assay. The FeO-NPs displayed a dose-dependent cytotoxicity property against breast carcinoma MDA-MB-231 cells, and the value of IC50 was found to be 304 μg/mL. The obtained FeO-NPs were used as photocatalyst in the degradation/reduction of environmentally polluted organic wastewater dyes. After 20 min of solar light irradiation shows 97 % of degradation efficiency was achieved with 1 mL of FeO-NPs. It is observed all the results, the green synthesized FeO-NPs could be effectively materials and used in several fields like industrial, agricultural, medical, food safety, and dye waste applications.

Synthesis and characterization of CuAl2O4 nanoparticles: Application for the removal of Eriochrome Black T under solar light irradiation

This work focuses on the use of the spinel CuAl2O4 as photocatalyst for the degradation of Eriochrome Black T (EBT), a potentially hazardous dye. CuAl2O4 is synthetized by co-precipitation and studied by physic-chemical and electrochemical properties. X-ray diffraction revealed the formation of a single phase with cubic symmetry with a homogeneous morphology. X-ray Photoelectron Spectroscopy (XPS) and FTIR spectroscopy provide a better understanding of the chemical composition and surface structure of CuAl2O4. Diffuse reflectance (DR) gave a band gap of 1.94 eV, attributed to Al3+ in octahedral configuration. The BET analysis led to a specific surface area of 37 m2/g with the availability of an appreciable surface for photochemical reactions. Chrono-amperometry indicated n-type conductivity of CuAl2O4, with electrons as dominant charges and an activation energy (Ea) of 0.17 eV. A flat band potential of 0.26 VSCE (Volt vs. Saturated Calomel Electrode) was calculated from the interfacial capacitance in Na2SO4 solution. The photoactivity of EBT degradation was assessed by using chemical oxygen demand (COD). A quasi-complete degradation of EBT was observed within 180 min under sunlight. The mineralization was carried out with an initial EBT concentration of 10 mg/L, a dose of 1 g/L at pH ∼ 8, similar to that of an aquatic environment. These experimental conditions are important to assess the applicability of this method in a real environment.

Silver-infused TiO2 nanowires and unveiling their potential for superior wastewater dye remediations.

Silver infused ultrathin TiO2 nanowires (NWs) were synthesized via a single step solvothermal approach. The crystallinity, structure, and morphology were determined to understand the physicochemical nature of the nanocomposites. The catalytic efficiency of the newly synthesized nanocatalysts was tested for the textile waste treatment taking methylene blue (MB) as model pollutant under solar light irradiations. Nearly 96% photodegradation efficiency for MB was achieved within 20 min. Furthermore, the recyclability of the photocatalyst was also studied, and the material remained stable and effective up to four consecutive runs. RESEARCH HIGHLIGHTS: Precise size-controlled synthesis of Ag-incorporated titania nanowires (ATNWs) Controlled aspect ratios, with tunable lengths and diameters (100-3 nm) via precursor and surfactant optimization Demonstrated ATNWs' efficiency in degrading toxic dye, methylene blue (MB) 96% photodegradation efficiency for MB achieved within 20 min using 3 nm thick annealed TiO2 NWs Recyclability efficiency of photocatalyst, which remained stable and effective for up to four consecutive runs.

Construction of ternary Ni2P/ZIF-8/CdS composite for efficient photocatalytic hydrogen production and pollutant degradation: Accelerating separation of photogenerated carriers

Constructing heterojunctions for efficient charge separation is a crucial method to boost photocatalytic activity. Initially, zeolitic imidazolate framework-8 (ZIF-8) nanoparticles were synthesized in situ on the surface of cadmium sulfide (CdS) nanoflowers, creating a novel ZIF-8/CdS composite material. Subsequently, a ternary Ni2P/ZIF-8/CdS composite was fabricated for photocatalytic hydrogen production and pollution reduction. The optimally obtained Ni2P/ZIF-8/CdS composites showed excellent photocatalytic efficiency and structural stability under simulated solar light irradiation. The hydrogen production rate of Ni2P/ZIF-8/CdS composite was 21.05 mmol h−1 g−1. Additionally, Ni2P/ZIF-8/CdS degraded malachite green (MG) with 99% efficiency. It was found that the proximity of sulfides to porous MOFs accelerated the separation of light-induced charges. Nickel phosphide (Ni2P) played a vital role in photocatalytic reactions, serving the dual function of capturing photogenerated electrons and accelerating separation of photogenerated carriers. Mechanistic and characterization studies revealed that constructing heterojunction between CdS and ZIF-8 could promote photogenerated carrier transport, enhance the separation efficiency of photogenerated carriers, ultimately improving the photocatalytic hydrogen production performance and degradation efficiency.

Concentrated Solar Light Photoelectrochemical Water Splitting for Stable and High-Yield Hydrogen Production.

Photoelectrochemical water splitting is a promising technique for converting solar energy into low-cost and eco-friendly H2 fuel. However, the production rate of H2 is limited by the insufficient number of photogenerated charge carriers in the conventional photoelectrodes under 1 sun (100mWcm-2) light. Concentrated solar light irradiation can overcome the issue of low yield, but it leads to a new challenge of stability because the accelerated reaction alters the surface chemical composition of photoelectrodes. Here, it is demonstrated that loading Pt nanoparticles (NPs) on single crystalline GaN nanowires (NWs) grown on n+-p Si photoelectrode operates efficiently and stably under concentrated solar light. Although a large number of Pt NPs detach during the initial reaction due to H2 gas bubbling, some Pt NPs which have an epitaxial relation with GaN NWs remain stably anchored. In addition, the stability of the photoelectrode further improves by redepositing Pt NPs on the reacted Pt/GaN surface, which results in maintaining onset potential >0.5V versus reversible hydrogen electrode and photocurrent density >60mAcm-2 for over 1500 h. The heterointerface between Pt cocatalysts and single crystalline GaN nanostructures shows great potential in designing an efficient and stable photoelectrode for high-yield solar to H2 conversion.

Dielectric, ferroelectric, optical and photocatalytic properties of Al and Ag-doped strontium hexaferrite (SrFe12O19) synthesized via facile micro-emulsion approach

Al and Ag-doped Sr1-xAgxFe12-yAlyO19 (x, y = 0.0, 0.2, 0.4, 0.6, 0.8) nano-materials (NMs) were prepared via a facile microemulsion approach and the effect of doping was appraised based on structural, optical, electrical and catalytic properties. The NMs were characterized by XRD, FTIR and UV-Vis techniques along with ferroelectric and dielectric properties. The NMs structure was hexagonal symmetric with crystallite size in the 23.3–30.2 nm range. The ferroelectric and dielectric properties were affected significantly in response to dopant content. The band-gap (Eg) values of NMs were in the 3.52–2.59 eV range. The photocatalytic efficiency (PCE) of bare strontium hexaferrite (SHF) and Sr1-xAgxFe12-yAlyO19 was evaluated against Methyl Orange (MO) dye (an anionic dye) and Rhodamine B (RhB) dye (a cationic dye) under solar light irradiation. The PCE of SHAF4 was 89%, while it was 52% in the case of SHF whereas for RB, SHF shows 66% and SHAF-4 represents 92% degradation. Pure SHF and SHAF-4 points of zero charge (pHzpc) were found to be 7.09 and 6.9, respectively. The remarkable PCE of the highest doped Sr1-xAgxFe12-yAlyO19 SHAF-4 makes this material a potential photo-catalyst for the removal of toxic dye from wastewater.

Pioneering superior efficiency in Methylene blue and Rhodamine b dye degradation under solar light irradiation using CeO2/Co3O4/g-C3N4 ternary photocatalysts

In this research work, we have successfully synthesized the CeO2/Co3O4/g-C3N4 ternary nanocomposite for hydrothermal method for photocatalytic applications. The synthesized nanocomposites were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Field emission scanning electron microscopy (FE-SEM), Transmission electron microscopy TEM, Photoluminescent spectra (PL), X-ray photoelectron spectroscopy (XPS), Brunauer- Emmett-Teller (BET) and Ultraviolet diffuse reflectance spectroscopy (UV-DRS) technique. As per the optical spectroscopic investigations CeO2/Co3O4/g-C3N4 ternary nanocomposite exhibited the high optical absorption range and its band gap is reduced from 2.95 eV to1.83 eV. The PL spectra showed the lowered emission peak intensity of ternary nanocomposite which is revealed that the better charge separation and slow recombination of electron hole pairs. The highest photocatalytic degradation efficiency of CeO2/Co3O4/g-C3N4 ternary nanocomposite showed 93 % and 86 % towards the pollutant methylene blue and Rhodamine B. Moreover, photodegradation of the pollutants followed pseudo-first order kinetics with a very high-rate constant of 0.02211 min−1 and 0.017756 min−1. Additionally, the ternary nano catalyst was delivered the remarkable stability performance even after five cycles. This research may provide a low-cost approach for synthesized visible light responsive catalysts for use in environmental remediation applications.

Improving adsorption and visible light photocatalytic performance of TiO2 via synergistic effect of nitrogen-doped graphene quantum dots and reduced mildly oxidized graphene oxide for cationic dye pollutants removal

In this study, a new type of ternary composite for efficient removal of cationic dye pollutants, P25/nitrogen-doped graphene quantum dots/reduced mildly oxidized graphene oxide (P25/NGQDs/rmGO) was successfully prepared by a two-step hydrothermal process. P25/NGQDs/rmGO exhibited outstanding removal performance towards methylene blue (MB), crystal violet (CV) and Basic Red 46 (BR46) under visible light or solar light irradiation owing to the excellent adsorption-photocatalytic property resulting from the synergistic effect of NGQDs and rmGO. The negatively charged NGQDs significantly improved the adsorption capacity for positively charged dye based on the adsorption experiment results. The investigations of adsorption kinetics and isotherm for MB demonstrated that the adsorption process followed the pseudo-second-order kinetic model and Langmuir adsorption isotherm, respectively. Thermodynamics analysis indicated that the adsorption process was exothermic and spontaneous. Furthermore, NGQDs and rmGO could both extend photoresponse range and enhance charge separation and transportation based on UV–vis DRS, PL spectra, transient photocurrent and electrochemical impedance spectra results. The optimized P25/NGQDs/rmGO composite obtained the removal efficiencies of 96.6 %, 100 % and 82.4 % for MB, CV and BR46, respectively, after 30-min adsorption and 150-min photodegradation under visible light irradiation. In addition, solar light irradiation was more favorable for the removal of these cationic dye pollutants. The high adsorption and photocatalytic degradation performance of P25/NGQDs/rmGO make it an excellent candidate for removing cationic dye pollutants from the industrial effluents. This study also provided a new idea on the roles of NGQDs and rmGO in adsorption-photocatalysis systems and promoted the practical application of TiO2-based composites in environmental field.

Application of natural solar photocatalytic and DSSC's studies AC loaded on Ag–In2O3 nanoparticles by hydrothermal approach

Contaminants are repeatedly being released into the land, water and air about the world as a consequence of the high levels of human movement and development, which causes a fast an increase in the growing of pollution. In this assessment, activated charcoals supported on Ag–In2O3 nanomaterials were blended by hydrothermal system. The morphology constitution, surface assets and optical description of synthesized nanomaterials were characterized by XRD, UV-DRS, PL, HR-SEM and EDAX, HR-TEM, SAED pattern, FT-IR, XPS, BET, CV and VSM techniques. The optimized heterogeneous catalyst AC/Ag–In2O3 depicts high electro catalytic activity, fast-charge transport development, weak ferromagnetism, brilliant accessibility and stability for Rh6G dye degradation, which is endowed for application in the alkaline medium. The prepared photocatalytic activity towards AC/Ag–In2O3 have been revealed as the degradation of Rhodamine 6G (Rh6G) dye in the presence of aqueous solution directed to solar light irradiation. AC/Ag–In2O3 is initiated to maintain some more efficient than synthesized Ag–In2O3 and In2O3 by pH9 positively mineralizing of Rh6G dye under sun light irradiation. The mineralization of Rh6G dye has been confirmed by measuring COD analysis. It is suggested that Rh6G degrades in the presence of solar light via a particular mechanism, which was discovered that the catalyst remained more stable and reusable. It has been effectively determined that the AC/Ag–In2O3 nanomaterial achieves photocatalytic effects.

Photocatalytic activity of ZnMn2O4/TiO2 heterostructure under solar light irradiation: Experimental and theoretical study

This study focuses on the application of the hetero-junction ZnMn2O4/TiO2 as an efficient photocatalyst for the degradation of Rhodamine B (RhB), a cationic dye. ZnMn2O4 was synthesized by sol-gel auto-combustion, employing citric acid as fuel. The photocatalysts underwent characterization by X-ray diffraction, Fourier Transform infrared spectroscopy, Scanning Electronic Microscopy with integrated EDX and UV–Vis Diffuse Reflectance. Creating a p-n heterojunction could significantly boost photocatalytic efficiency. In this work, we use TiO2 as a n-type co-catalyst to enhance electron transfer efficiency. The ZnMn2O4 spinel exhibits direct optical transition at 1.97 eV, while TiO2 displays an indirectly allowed transition at 3.24 eV. Mott-Schottky plots revealed flat band potentials of -0.121 and +0.3 V/SCE for ZnMn2O4 and TiO2, respectively. Kinetic data of RhB adsorption were fitted using the pseudo-second order model. The heterojunction p-ZnMn2O4/n-TiO2 demonstrates a significant pollutant degradation rate, with 95% removal within 180 min under sunlight irradiation, surpassing the effectiveness of ZnMn2O4. To validate the experimental results, a theoretical investigation was conducted using density functional theory (DFT) and molecular dynamics (MD) simulations. Geometry optimization of the Rhodamine B molecule was studied in both gas and liquid phases, and various quantum chemical parameters were computed. Molecular dynamics simulations were additionally employed to examine the dynamic behavior of Rhodamine B adsorption on ZnMn2O4 (211) and TiO2 (101) surfaces in an aqueous environment.

Iron-Based nanoporous Metal-Organic frameworks with Side-Chain amino substituents for Efficiency-Regulated oxygen evolution reaction

Nanoporous iron-based MOFs, possessing notable attributes such as adjustable structure, considerable porosity, and large surface area, exhibit considerable promise for various applications in the field of photocatalysis. However, the effect of the ligand substitution ratio on the photocatalytic reaction process is currently unknown. In the current investigation, a series of iron-based MOFs MIL-101(Fe)-X with various ratios of amino substituents (X = H: NH2 = 1:0, 1:0.5, 1:1, 1:2, 1:4, 0:1) were synthesized using the solvothermal method. The morphology and structure were characterized using SEM, TEM, XRD, XPS, BET, FT-IR, etc. Their efficacy as water oxidation catalysts under AM1.5G (solar light) irradiation was investigated. The findings of the study indicated that MIL-101(Fe) with an X value of 1:2 exhibited the highest surface area of 380.4 m2/g. This resulted in the exposure of a greater number of active sites, leading to enhanced charge separation efficiency and exceptional oxygen evolution activity when illuminated by simulated sunlight. The oxygen evolution rate under solar light was measured to be 11.7 mmol·h−1·g−1. This research confirmed the effect of substituent variation on the oxygen evolution rate by modulating the substitution ratio of side-chain ligands on MOFs, thereby altering their microstructure and charge distribution. The incorporation of a suitable quantity of amino groups, that act as strong electron-donating groups, facilitated the effective separation of electron-hole pairs generated during the photocatalytic process. However, an excessive introduction of amino groups can result in a reduction in both pore structure and surface area, thereby impeding the efficiency of the photocatalytic oxygen evolution reaction.

WO3–NiO/rGO Based Photocatalyst for Effectively Degradation of Colored and Colorless Pollutants Using Solar Light Irradiation

WO3–NiO/rGO Based Photocatalyst for Effectively Degradation of Colored and Colorless Pollutants Using Solar Light Irradiation

Design of novel solar-light-induced KBi6O9I/Ag–AgVO3 nanophotocatalyst with Ag-bridged Z-scheme charge carriers separation and boosted photo-elimination of hospital effluents

In this research, a novel solar-light-induced KBi6O9I/Ag–AgVO3 nanophotocatalyst with an Ag-bridged Z-scheme structure has been designed and synthesized through a sonochemical method to photo-degrade antibiotic hospital contaminants under simulated solar-light irradiation. Synthesized nanophotocatalysts with varying KBi6O9I to Ag–AgVO3 weight ratios underwent N2 Adsorption-Desorption, XRD, TEM, UV–Vis DRS, FESEM and PL analyses. The Ag-bridged Z-scheme-structured KBi6O9I/Ag–AgVO3 (1:1) nanophotocatalyst, demonstrated broad light absorption within the solar-light spectrum and showcased effective photocatalytic efficacy in degrading tetracycline antibiotic (88.3% and 83.5% removal for 25 and 50 mg/L, respectively, after 120 min). This performance outperformed other composited photocatalysts, as well as pure Ag–AgVO3 and KBi6O9I photocatalysts. The enhanced degradation efficiency of the KBi6O9I/Ag–AgVO3 (1:1) composite can be ascribed to the synergistic interaction of various elements. These include the surface plasmon resonance impact of silver nanoparticles, their pronounced sensitivity to solar irradiation, and the Z-scheme heterojunction configuration. Collectively, these factors work together to minimize the recombination rate of photoinduced electron-hole pairs, thereby amplifying the efficacy of photodegradation. Furthermore, the KBi6O9I/Ag–AgVO3 (1:1) composite photocatalyst displayed sustained pollutants elimination performance even after undergoing four consecutive cycles.

S-scheme homojunction and activate site engineering over TiO2 for highly efficient photocatalytic nitrogen fixation

The presence of efficient catalytic active sites and an ample supply of electrons are the two indispensable factors for achieving photocatalytic nitrogen fixation. Herein, the Fe-doped TiO2 S-scheme anatase/rutile homojunction (F-T-A/R) was synthesized as a brilliant photocatalyst for photocatalytic nitrogen fixation from N2 to NH3 under ambient atmosphere. The optimized F-T-A/R photocatalyst (A/R = 98:2, Fe-2 wt%) exhibits an unprecedented NH3 generation rate of 358 μmol gcat-1h−1 in water solvent and under simulated solar light irradiation. Experimental and theoretical studies reveal that the constructed S-scheme homojunction in F-T-A/R is conducive to fluent charge separation and adequate supply of electrons on rutile with higher nitrogen fixing activity, while the tuned local electronic structure of oxygen vacancy with Fe doping is engineered to strengthen active sites, synergistically enhancing the photocatalytic nitrogen fixation.

Antibacterial, antifungal and photocatalytic evaluation of Gd2O3-Fe2O3-CoO heterostructured photocatalyst

ABSTRACT In the present work, the tri-phase of Gd2O3-Fe2O3-CoO heterostructured ternary nanocomposite was synthesised via a facile co-precipitation method to investigate the antimicrobial and photocatalytic potential. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDX), and BET (Brunauer-Emmitt-Teller) analysis were used to examine the functional group detection, phase purity, surface morphology elemental detection and surface area of synthesised nanocomposite. The antibacterial study against Staphylococus aureus, Pseudomonas aeruginosa, Escherichia coli, and Bacillus subtilis bacterial strains was evaluated. The results showed higher activity against Pseudomonas aeruginosa with ZOI 26 mm. The antifungal test against Aspergillus flavus and Aspergillus niger was evaluated. The results showed higher activity against Aspergillus flavus with less growth of fungi around the composite. Methylene blue (MB) dye and Ciprofloxacin (CIP) drug were used as target pollutants to evaluate the photocatalytic performance of catalyst under solar light irradiation. The ternary composite exhibited 93% and 96% degradation efficiency towards MB and CIP at pH = 11, and pH = 7, respectively in 120 min which is higher than pure Gd2O3, Fe2O3 and CoO. Furthermore, active species trapping tests with various scavengers elucidate a possible mechanism, indicating that •O2 _and •OH radicals play a critical part in photodegradation reaction.

An Innovative Sunlight‐Driven Device for Photocatalytic Drugs Degradation: from laboratory‐ to real‐Scale Application. A First Step Toward Vulnerable Communities

AbstractFreshwater represents one of the most precious resources on the planet, so it is fundamental to preserve it. In this work, an innovative sunlight‐driven device composed of bismuth oxybromide (BiOBr) grown on a material derived from natural sources, i.e., Lightweight Expanded Clay Aggregates (LECA), is developed to clean surface waters under natural solar light irradiation. For this purpose, the photodegradation of two non‐steroidal anti‐inflammatory drugs, ibuprofen, and diclofenac, is investigated under varying operative conditions. Laboratory‐ and real‐scale experiments reveal that the fabricated floating BiOBr/LECA photocatalyst fully degrades diclofenac, whereas limited abatement of ibuprofen is observed. Based on the identification of specific transformation products (TPs) during the degradation, this behavior seems to be strongly related to the different structures of the two drugs. In fact, the main TP produced during diclofenac degradation derives from dechlorination and ring condensation: this type of photocatalytic degradation pathway is generally favored over the C─C bonds's cleavage, which is a unique possibility for IBU abatement. Moreover, the potential partial adsorption of these species on the photocatalyst's active sites can cause their deactivation. Finally, reusability tests demonstrate the high stability of the floating composite.