Visible Light Photocatalytic Performance Research Articles

Boosting visible-light photocatalytic performance of graphitic carbon nitride by regulating its donor-acceptor structure via maleamide

Graphitic carbon nitride (GCN) has attracted much attention due to its many advantages as a kind of photocatalyst, including low cost, easy to prepare, eco-friendly and so on. However, GCN suffers from limited light-absorption capacity and rapid recombination of photogenerated charge carriers. Herein, a new kind of photocatalyst based on GCN has been synthesized by introducing a small molecule compound (maleamide) through a facile thermal polycondensation method (550 ℃ for 180 min) and applied it to photocatalytic removal of bisphenol A (BPA). The optimized GCN-20 (20 mg maleamide in 10 g urea) exhibits the best BPA degradation performance and good stability. The UV–vis test shows that the introduction of maleamide broadens the optical response threshold of GCN from 435 nm to 460 nm. The promoted photocatalytic performance is mainly attributed to enhanced donor-acceptor structure by electron-withdrawing group, which accelerates charge separation and inhibits recombination of free holes and electrons. The active species including superoxide radicals (⋅O2-), hydrogen peroxide (H2O2) and hydroxyl radicals (⋅OH), play dominant roles in the photocatalytic degradation process.

Design and synthesis of in situ self-assembled PDI/Bi2MoO6 complexes: Promoting singlet oxygen selective generation and visible light photocatalytic purification performance

Solar-driven photocatalytic degradation of antibiotics has emerged as an eco-friendly approach to treating wastewater. And singlet oxygen is a selective and highly active reactive oxygen species. Bi2MoO6 microsphere photocatalyst modified by narrow band gap PDI organic supramolecular was prepared by water bath heating method to achieve the selective generation of non-free radical. It focused on the effects of different acid-induced assembled and different light sources on the photocatalytic performance of PDI/Bi2MoO6 (PDI/BMO) photocatalysts and explored their ability to remove various pollutants. The results showed that PDI/BMO composites self-assembled with nitric acid (1% PMN) could effectively purify a variety of pollutants under visible light irradiation, including CIP, TC, LVF and AO7. In addition, 1% PMN showed excellent photocatalytic performance in actual water, and even have fair degradation efficiency under red light irradiation. Holes and singlet oxygen were confirmed to be the main reactive oxygen species during CIP degradation by capture experiments and EPR, and the steady-state concentration of singlet oxygen was quantified. Three degradation pathways of CIP under the action of non-radicals were clarified, and the biotoxicity of CIP treated products was evaluated by bacteriostatic experiments. This work could provide an ecologically friendly method for wastewater treatment.

A novel S-scheme photocatalyst Fe2O3/Bi2O3/g-C3N4 with enhanced visible-light photocatalytic performance for antibiotic degradation and CO2 reduction: RSM-based optimization

The degradation of pollutants and reduction of CO2 to hydrocarbon fuels using photocatalysis is a potential approach to reducing CO2 emissions and decreasing environmental contamination. This study introduces an innovative S-scheme photocatalyst (Fe2O3/Bi2O3/g-C3N4) synthesized through simple methods for the first time. The structural, morphological, and optical properties of the synthesized photocatalysts were comprehensively characterized using XRD, XPS, FTIR, SEM, TEM, HR-TEM, BET, UV–vis DRS, PL, ESR, and mott-Schottky analyses, respectively. The visible light photodegradation of tetracycline (TC) antibiotic and CO2 conversion were carried out in order to evaluate the photocatalytic performance of these synthesized materials. Using the RSM-CCD approach, the influence of key variables on TC degradation were optimized. The results indicated that the optimized photocatalyst (45-FeBiC) exhibited higher photocatalytic performance (99.87 %) compared to other samples via photogenerated •O2−, and •OH. Additionally, four cycle studies verified that the 45-FeBiC nanocomposite had adequate photostability. After 6 h of visible light illumination, the 45-FeBiC catalyst generated 33.84 μmol/g of CO and maintained 96.2 % of its initial photocatalytic activity after 30 h of reaction. The enhanced photocatalytic efficiency of the 45-FeBiC nanocomposite is attributed to the photosensitization effect of 3 wt%-Fe2O3/Bi2O3 on g-C3N4 within the S-scheme photocatalytic framework.

α-Fe2O3/MoS2 heterostructured nanomaterial for enhanced visible-light photocatalytic performance under sunlight irradiation

α-Fe2O3/MoS2 heterostructured nanomaterial for enhanced visible-light photocatalytic performance under sunlight irradiation

Three-dimensional crosslinked structure assembled by novel elemental iodine doped Nb2O5 ultrathin nanosheets for exceptional visible-light photocatalytic performance

The application of Nb2O5 in photocatalysis has sparked interest due to its potent oxidation capabilities and eco-friendly properties. However, challenges such as poor visible light response, limited reactive active sites and rapid charge recombination still hinder its practical use. Herein, a novel approach introduces elemental I-doped Nb2O5 (INO) catalyst with a three-dimensional crosslinked structure formed by ultrathin nanosheets, for the first time. This pioneering approach results in the INO catalyst with a high specific surface area (98.51 m2 g−1), abundant active sites, and enhanced visible light absorption. The dispersion of elemental I within the Nb2O5 lattice promotes the presence of delocalized electrons and improves charge carrier mobility, leading to superior catalytic performance for the degradation of diclofenac (DCF). During a 75-min period, the degradation efficiency of INO catalyst to diclofenac was found to reach 91.5 %, with a corresponding rate constant of 35.0 × 10−3 min−1. Furthermore, the study investigates the DCF degradation pathway and the toxicity changes in its byproducts. This innovative research opens new avenues for enhancing the visible light catalytic activity of Nb2O5 catalysts.

Low dose, high function: Visible light photocatalytic performance of in-situ sensitized Ti3+/Ov self-doped rutile TiO2-x nanorods with a small amount of ultrathin g-C3N4 nanosheets

Harnessing solar energy for photocatalytic sewage purification represents a significant strategy for addressing water pollution. This study focused on synthesizing ultrathin g-C3N4 nanosheets through ultrasonic refluxing g-C3N4 aggregates in a mixture of water and triethylamine. Subsequently, Ti3+/oxygen vacancy (Ov) self-doped rutile TiO2 (TiO2-x) nanorods were synthesized via an in-situ mixed solvothermal reaction. By sensitizing a minimal quantity of these ultrathin g-C3N4 nanosheets, a Z-scheme heterojunction with reduced rutile TiO2-x nanorods was achieved. Various analytical techniques were employed, including X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS), and transient photocurrent analysis. These methods determined the phase, structure, morphology, and photoelectrochemical properties of the fabricated materials. The visible light photocatalytic performance was tested using rhodamine B, methyl orange, and Cr2O72- solutions as simulated pollutants and three distinct types of actual wastewater from a pharmaceutical factory as photocatalytic degradation object. The findings revealed that Ti3+/Ov self-doping significantly enhances the visible light responsiveness of rutile TiO2. The integration of minimal amounts of ultrathin g-C3N4 nanosheets with rutile TiO2-x nanorods, formed via an in-situ mixed solvothermal reaction, effectively promoted the separation of photogenerated electrons and holes, thereby increasing the photocatalytic efficiency. Interestingly, increasing the g-C3N4 content in the mixture led to an increase in the number of defects within TiO2-x and a reduction in crystallinity. Wastewater treatments yielded varied results: wastewater containing solely phenols underwent effective photocatalytic degradation, while samples with high salt content or complex compositions proved more challenging. This study demonstrated that the heterojunction formed by sensitizing rutile TiO2-x nanorods with a small amount of ultrathin g-C3N4 nanosheets retained remarkable photocatalytic activity. These findings offer valuable insights for the design of effective photocatalysts and their application in sewage treatment.

Insights into effect of dopant site and dopant concentration on structural, electronic and optical properties of GaNbO[formula omitted] and its implications on visible light photocatalytic behavior: An ab-initio study

First principles electronic structure calculations were performed on pure and chalcogenide doped GaNbO4. Doping with isoelectronic S and Se at the O sites in GaNbO4 shows a dopant site driven anisotropy in the structural properties which affects its electronic, optical and photocatalytic behavior. Band gap reduction in GaNbO4 is more with Se than S and this reduction can be regulated via choice of dopant, dopant site and dopant concentration. GaNbO4 bears an optical absorption profile similarity with anatase TiO2 (a-TiO2). Besides directional anisotropy, dopant induced absorption in the visible regime displays a site driven anisotropy, which, has implications on the onset of absorption and absorption peak heights. The visible region absorption peaks can be modulated with changes in the dopant concentration. Se dopant at a lower concentration gives a broader visible regime absorption peak of similar peak height as of a higher concentration S dopant. Undoped GaNbO4 has valence band maxima and conduction band minima at similar energies as a-TiO2 and these band placements can be altered through choice of dopant element, dopant site and dopant concentration to tune the visible light photocatalytic performance. Our study shows that doped GaNbO4 has a stronger visible range absorption than doped a-TiO2.

Sensitizer created defective metal organic framework as a new platform for boosting visible-light photocatalysis of g-C3N4

We developed herein for the first time a sensitizer created defective MOF (SCD-MOF), simultaneously possessing sensitizers and defects as visible-light harvester and electron trapper, respectively, which can synergistically improve the visible-light photocatalysis of polymeric graphitic carbon nitride (g-C3N4). Based on this discovery, the resulting 5.0 wt% FeTCPP⊂UiO-66@g-C3N4 shows a significant 6.6 and 3.9 times improvement in catalytic efficiency compared with its parent materials of FeTCPP⊂UiO-66 and g-C3N4 in degrading organic pollutants. Moreover, it shows a 10.4 times enhancement in catalytic efficiency compared with commercial TiO2 (P25). Mechanism studies suggest that sensitizer molecules and defects in SCD-MOF can synergistically improve photocatalytic efficiency because of broadening the visible-light response and strengthening the charge carrier separation. This work illustrates a remarkably triple synergetic effect among visible-light harvester, electron/hole separator, and semiconductor and thus established SCD-MOF as a class of new platform to greatly improve the visible-light photocatalytic performance of conventional semiconductors.

Engineering oxygen vacancies and morphology of BiOCl microspheres via electrification to enhance visible light photocatalytic performance

Enhancing the separation efficiency of photo-generated carriers and the surface area of catalysts is beneficial to improve the photocatalytic performance, which is critical to achieving application of photocatalysis in practical environmental remediation. In this work, the BiOCl microspheres were treated with electrification for the first time to synergistically tune oxygen vacancies (OVs) and microstructure. With 6 h electrification, the photocatalytic performance of BiOCl-6 microspheres was significantly enhanced, which can not only degrade organic contaminants, but also effectively reduce toxic heavy metal ions. The photocatalytic reaction rates for methyl blue (MB), ciprofloxacin (CIP) and hexavalent chromium Cr(VI) reached 0.071, 0.056 and 0.097 min−1, respectively, which were 5.1, 7.0 and 8.1 times higher than that of pristine BiOCl. The density functional theory (DFT) calculations and experimental investigation suggest that the designed OVs facilitates the separation of photo-excited carriers and expands the light adsorption range of BiOCl. Meanwhile, the increased surface area of BiOCl-6 microspheres enhances the adsorption for contaminants and provides more active sites for photocatalytic reaction. This work provides a new approach to synergistically enhance photocatalytic performance for photocatalysts by vacancy engineering and morphology control.

Direct Z-scheme charge transfer Bi2O3/UiO-66-NH2 heterojunctions for boosted photocatalytic degradation of tetracycline hydrochloride in different water systems

The development of hybrid heterostructure photocatalysts with enhanced visible light absorption capacity holds significant importance in environmental remediation. However, the challenge persists in exploiting strong visible-light responsive photocatalysts with both high efficiency and stability. Herein, we successfully synthesized a hybrid Z-scheme heterojunction of Bi2O3 and UiO-66-NH2 (Bi2O3/UiO-66-NH2) through a simple hydrothermal route. The visible light photocatalytic performance of Z-scheme Bi2O3/UiO-66-NH2 heterojunction is systematically evaluated for persistent antibiotic tetracycline hydrochloride (TC-HCl) both in the clean and real water matrix. All heterojunction catalysts exhibit superior photodegradation capabilities compared to pristine Bi2O3 and UiO-66-NH2. The optimal ratio of the two components heterojunction (BUN-150), in particular, demonstrates the highest removal efficiencies for TC-HCl (95 %) within a 90-min timeframe. This remarkable photocatalytic performance is credited to the Z-scheme charge transfer occurring at the interface of Bi2O3 and UiO-66-NH2 in Bi2O3/UiO-66-NH2 heterojunction. The active species experiments and electron paramagnetic resonance analyses are conducted to identify the active reactive species during the TC-HCl degradation (·OH, h+, and ·O2−), and a precise photocatalytic degradation mechanism is explained. Additionally, the photodegradation intermediates of TC-HCl are detected using the HPLC-MS analysis to explain the degradation pathways of TC-HCl. This research paves the way for the development of novel Z-scheme Bi2O3-based heterojunction catalysts for outstanding photocatalytic applications.

Design and fabrication of Zeolite Socony Mobil-5 incorporated ZnO composite for enhanced visible light photocatalytic performance

In this study, a hydrothermal method was used to synthesize a ZSM-5/ZnO nanocomposite which was used to photocatalytic activity degrade methylene blue (MB) and Rhodamine B (RhB) dye in an aqueous solution. The structure, morphology, composition and optical and textural properties of the composites were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and UV– vis diffuse absorption spectroscopy (UV–vis DAS), photoluminescence (PL) and N2 adsorption/desorption, respectively. TEM images showed the ZnO nanorods were uniformly embroidered on the surface of ZSM-5 sphere surfaces, and the embroidered ZnO nanorods had an average size of 80 ± 20 nm. The presence of ZnO in ZSM-5 leading resulted in a increase in the surface area (125.6 m2/g) and pore size (21.3 nm) as confirming by nitrogen adsorption-desorption isotherm experiments. The ZnO/ZSM-5 composite was further used as a photocatalyst material in the dye (methylene blue: MB and Rhodamine B: RhB) degradation process, and the performance was compared with that of pure prepared ZnO. Moreover, the degradation efficiency of the ZSM-5/ZnO composite for MO degradation was found to be ∼92 after 180 min, which is higher than that of the pure ZSM-5. While, the degradation efficiency of ZSM-5/ZnO composite was found to be 98.5 % towards RhB dye under identical experimental conditions. The ZSM-5/ZnO composite was also extensively reused for five photo degradation cycles without experiencing any significant changes in its activity or crystalline characteristics.The improved mechanism was also discussed in detail.

Designing a NiFe-LDH/MnO2 heterojunction to improve the photocatalytic activity for NOx removal under visible light

2D/2D heterojunctions between ultrathin NiFe-CO3 layered double hydroxide (LDH) and varying amounts of birnessite (δ-MnO2) were prepared using an environmentally friendly and cost-effective self-assembly method. The prepared samples have proven to be efficient in their application, mitigating NOx emissions via a photooxidative process. The effective creation of 2D/2D NiFe–LDH/MnO2 heterojunctions has been verified through a variety of characterisation techniques, such as XRD, FT-IR, TGA, XFR, N2 adsorption–desorption isotherms, HRTEM and SEM images, EDX, and XPS. Photocatalytic measurements have indicated that the heterojunction formed between NiFe-LDH and MnO2 modifies its photoconductive behaviour, significantly enhancing the visible light photocatalytic performance of the partners. Finally, the optimal relationship between NiFe-LDH and MnO2 in the photocatalytic process was studied. It was found that a ratio of 10:1, respectively, exhibited superior properties compared to the other composites, highlighting the best performance in the degradation of NO under visible light and notable stability during the recycling process.

Controlled Synthesis and Catalytic Performance of Ag3PO4 Polyhedra Photocatalysts

Ag3PO4 is an effective green photocatalyst that exhibits higher visible light photocatalytic performance for the degradation of various organic pollutants. The photocatalytic performance of Ag3PO4 is affected by the exposed high‐energy crystal facets. Herein, Ag3PO4 with different morphologies and specific surfaces is synthesized via a direct precipitation method in the presence of triethanolamine (TEA). The Ag(TEA)n complex, which served as an intermediate medium, plays a critical role during the morphological transformation. When the molar ratio of Ag+ to TEA is set as 1:12, 18‐facet polyhedral morphology of Ag3PO4 crystals is obtained. The spherical and dodecahedral samples are also obtained by adjusting the molar ratio of Ag+ to TEA as 1:1 and 1:14. The photocatalytic activity of the samples for the degradation of methylene blue (MB) is tested under visible light irradiation. It is demonstrated when the molar ratio of Ag+/TEA is 1:12, Ag3PO4 polyhedra with 18‐facet are fabricated. X‐ray diffraction and scanning electron microscopy results indicate that the 18‐facet polyhedron, with six {100} facets and twelve {110} facets, enjoys the most exposed high‐energy crystal facets. Photocatalytic experiments show that the 18‐facet polyhedron has the best performance, and the degradation of MB by Ag3PO4 polyhedron with 18‐facet morphology reaches 90% within 70 min.

Construction of an all-organic S-scheme heterostructure based on PEDOT immobilized g-C3N4 nanosheets by electrostatic self-assembly with enhanced visible-light photocatalytic hydrogen production

Inspired by photosynthesis in nature, exploring all-organic S-scheme heterojunction photocatalysts for efficient H2 production is of great significance in addressing energy shortage issues. In this paper, poly(3,4-ethylenedioxythiophene) (PEDOT) immobilized g-C3N4(CN) nanosheets were constructed by an electrostatic self-assembly strategy to obtain an all-organic S-scheme heterojunction, significantly enhancing the visible-light photocatalytic H2 production performance of g-C3N4. The optimized 5PEDOT/CN exhibits the highest H2 production rate of 3.15 mmol g−1h−1, a 31.5-fold enhancement over pristine CN. According to the staggered energy band positions of two components and the results of electron spin resonance tests, the S-scheme heterojunction electron-transfer mechanism is confirmed, which greatly facilitates the spatial charge separation and retains the strong reducing ability of high-energy potential electrons for efficient photocatalytic H2 production. Based on the results of FT-IR spectra, XPS spectra, fluorescence spectra, hydroxyl radical tests and time-resolved photoluminescence spectra, it is confirmed that the significantly improved photocatalytic activity is mainly attributed to the enhanced charge separation by the S-scheme heterojunction and the tightly contacted interface dependent on N···S interactions in PEDOT immobilized CN nanosheet heterojunctions, along with the enhanced visible-light absorption ability. This work presents a novel approach to the design and fabrication of all-organic S-scheme heterojunction photocatalysts for solar-light-driven energy production.

Synthesis and characterization of bi-functional Cu and Ni co-doped ZnO photocatalysts for organic pollutant degradation and antimicrobial activity

The study of visible light active photocatalysts for organic pollutants degradation and antimicrobial activity has gained significant attention in recent years. Herein, we report the synthesis of pure ZnO, Ni-doped ZnO (Ni-ZnO), Cu-doped ZnO (Cu-ZnO), and Cu and Ni co-doped ZnO (CuNi-ZnO) photocatalysts via a facile coprecipitation method. These photocatalyst materials were characterized using various analytical techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscope (HR-TEM), Fourier transform infrared spectroscopy (FTIR), UV–visible spectroscopy (UV–Vis), photoluminescence (PL), and total organic carbon (TOC) analysis. XRD patterns confirm the presence of a mixed phase in the CuNi-ZnO sample. The presence of Cu, Ni, and Zn in CuNi-ZnO was verified through the XPS spectra. The nanoparticle-like morphology of the CuNi-ZnO photocatalyst was confirmed using HRTEM analysis. The FTIR spectra reveal the chemical bonds present in the materials. UV–visible spectroscopy was employed to determine the band gap of the materials, revealing a value of 3.10 eV for CuNi-ZnO. The mitigation in recombination of excited electrons (e−) and holes (h+) in CuNi-ZnO is validated through photoluminescence (PL) studies. The synthesized materials were used for the degradation of Indigo carmine (IC) dye and antimicrobial activity. The results showed that the optimized CuNi-ZnO sample displayed a better visible light photocatalytic performance (93.32 % IC dye degradation efficiency in 60 min) than the other samples. A notable degree of mineralization was observed with a reduction in total organic carbon (TOC) reaching 65.91 %. Additionally, the photocatalyst showed antimicrobial activity against both S. aureus and E. coli. Furthermore, a plausible visible light photocatalytic mechanism was proposed for the degradation of IC dye using the CuNi-ZnO photocatalyst.

Visible light photocatalytic performance of Co/Ag bimetallic coordination polymer catalysts designed from hard and soft acid-base theory

Heterometallic coordination polymers have promising applications in photocatalysis, and the design and selection of suitable organic ligands and coordination metals is the key to improve the catalytic activity of polymer photocatalysts. Herein, a novel Co/Ag bimetallic coordination photocatalyst, designed based on the hard and soft acid-base (HSAB) theory, has been successfully prepared by a stepwise method with Ag-S coordination as the main component and Co-N/Co-S as the complementary component. The obtained Co/Ag photocatalyst demonstrates excellent performance in the photocatalytic degradation (visible light) of halogenated phenolic pollutants. Degradation of 10 ppm of 4-chlorophenol could reach 100 % in 4 h, and 70 % degradation of 4-fluorophenol, which is even more difficult to degrade, could also be achieved. In addition, hydrogen production experiments conducted under visible light irradiation showed that the hydrogen production could reach 36.95 μmol h−1 g−1 for 6 h, which strongly demonstrated the excellent reduction ability of Co/Ag photocatalysts. The photocatalyst exhibits enhanced photocatalytic activity which is ascribed to the formation of Ag-S and Co-N/Co-S coordination, which greatly increases the charge density and facilitates charge transfer. Thus, the photogenerated electrons can induce both the conversion of O2 to •O2- for oxidation reactions, as well as the direct attack of the C-Cl bond for reduction reactions. This study demonstrates the successful design of the synergistic Co/Ag bimetallic coordination photocatalysts based on the HSAB theory, thereby offering a promising research avenue for the fabrication of heterometallic coordination photocatalysts.

Ornamental kale-like ZnO nanostructure/CdS nanoparticle/MoS2 nanosheet ternary heterojunctions for efficient charge transfer and robust visible-light photocatalytic performance

Photocatalytic technology utilizing Z-scheme protocol offers a promising method for eliminating contaminants from water in the presence of visible light. In this work, by combining hydrothermal and chemical deposition methods, a new type of ornamental kale-like ZnO nanostructure/CdS nanoparticle/MoS2 nanosheet (ZCM) ternary photocatalyst was fabricated, which exhibits excellent visible light photocatalytic performance. A small amount of MoS2 nanosheets significantly improves the activity of the double Z-scheme ZCM photocatalyst. As compared to ZnO/CdS, the pseudo-first-order kinetic constant of the best ZCM sample for degradation of rhodamine B is 2.2 times higher. In light of free radical capture and PL results, a Z-scheme transport mechanism was revealed to increase the carrier separation rate and maintain strong redox stability. This study provides a solid basis for designing Z-scheme photocatalysts and developing a range of visible light-responsive photocatalysts.

Enhanced visible light photocatalytic performance of carbon and oxygen co-doped carbon nitride with a three-dimensional structure: Performance and mechanism study

As a cost-effective photocatalyst, carbon nitride (g-C3N4) holds tremendous promise for addressing energy shortages and environmental pollution. However, its application is limited by disadvantages such as low specific surface area and easy recombination of photogenerated electron-hole pairs. This study introduces C and O co-doped g-C3N4 with a three-dimensional (3D) structure achieved through a straightforward one-step calcination process, demonstrating excellent photocatalytic activity of hydrogen production and oxytetracycline degradation, with superoxide radicals as the primary active species. We propose a plausible enhanced mechanism based on systematic characterizations and density functional theory calculations. The 3D structure confers a substantial specific surface area, enhancing both the adsorption area and active sites of catalysts while bolstering structural stability. Co-doping optimizes the band structure and electric conductivity of the catalyst, facilitating rapid migration of photogenerated charges. The synergistic effects of these enhancements significantly elevate the photocatalytic performance. This study presents a convenient and feasible method for the preparation of dual-regulated photocatalysts with outstanding performance.

Facile construction of a novel S-scheme Fe2TiO5/BiVO4 photocatalyst for efficient visible light-driven fenton-like degradation of ciprofloxacin

The rational design and fabrication of stable and efficient heterogeneous Fenton-like catalyst is of great significance for wastewater treatment, but is still fraught with obstacles. In this paper, a novel S-scheme Fe2TiO5/BiVO4 nano-heterojunction with high visible-light photocatalytic performance was synthesized by an in-situ growth method. The optimized Fe2TiO5 (20 wt%)/BiVO4 composite exhibited remarkable photocatalytic activity and rapid degradation ability towards CIP (50 mg/L) with the addition of H2O2 (20 mM), achieving a removal efficiency of 94.2 % within 90 mins. This performance is significantly superior to that of pure BiVO4 (43.8 %) or pure Fe2TiO5 (48.2 %). The S-scheme heterojunction formed between Fe2TiO5 and BiVO4 facilitates efficient charge separation, and preserves the powerful photogenerated electrons in CB of Fe2TiO5 and holes in the VB of BiVO4, contributing to the fast degradation of CIP. The synergistic effects of the S-scheme heterojunction and H2O2 activation account for the excellent performance of Fe2TiO5/BiVO4 photocatalyst. The prepared photocatalyst demonstrates remarkable efficiency, non-selectivity, exceptional stability, and adaptability to various environmental conditions. This study proposes a novel approach for designing and synthesizing photo-assisted Fenton-like S-scheme photocatalysts for efficient removal of organic pollutants in wastewater.

Controlled synthesis of Cadmium doped CuBi2O4 nanorods with rapid and synergistic visible light photocatalytic performance

The rise of nanotechnology has significantly influenced the synthesis of advanced photo materials and their various potential applications. In this study, newly advanced multicomponent photocatalyst was designed by a simple hydrothermal method i.e., CuBi2O4, Cd0.05Cu0.95Bi2O4, Cd0.1Cu0.90Bi2O4, and Cd0.15Cu0.85Bi2O4. These nanostructures were characterized using various spectroscopic techniques. The synthesized nanostructure material was tested for decontaminating water polluted with Congo red, using visible light irradiation. Within 60 min of irradiation, Cd0.1Cu0.90Bi2O4 exhibited 91 % degradation of Congo red, while Cd0.05Cu0.95Bi2O4 and Cd0.15Cu0.85Bi2O4 showed degradation rates of 80 % and 86 % respectively. In contrast, the pure CuBi2O4 had a lower photo degradation rate of 70 % over 70 min of visible light irradiation. Among the synthesized materials, Cd0.1Cu0.90Bi2O4 demonstrated the highest efficiency, require the shortest time to achieve significant degradation. Additionally, the impact of various parameters such as dosage, initial concentration, hydrogen peroxide, and salts on the photo-catalytic degradation of the dye has been studied. Consequently, it can be concluded that the use of hierarchical porous Cd0.1Cu0.90Bi2O4 photocatalyst holds promising potential in wastewater remediation.