Facile assembly and excellent elimination behavior of porous BiOBr-g-C3N4 heterojunctions for organic pollutants

Enhancing the adsorption-photocatalytic efficiency of BiOBr for Congo red degradation by tuning the surface charge and bandgap via an Y3+-I- co-doping strategy

Metal-ion doping and halogen substitution have been largely applied to tune the bandgap of bismuth oxybromide (BiOBr) to upgrade its photodegradation capacity. In this work, the adsorption capacity and photocatalytic behavior of solvothermally synthesized BiOBr photocatalysts can be optimized via the synergistic effect of Y3+- and I--doping. After an adsorption reaction in the dark and exposure for another 80 min to visible light, pure BiOBr can remove 46.5% of Congo red (CR) from water with an initial CR concentration of 50 mg L-1. Meanwhile, Bi0.8Y0.20OBr0.97I0.03, the co-doped catalyst, displays total degradation rates exceeding 98% and 92% with CR dosages of 50 and 100 mg L-1, respectively, demonstrating a doubled degradation capacity. With the co-doping solution, the negative charges on the catalysts reduce, more oxygen vacancies are generated, the bandgap remarkably narrows, and the photoabsorption range broadens for derivation of photoinduced electron-hole pairs. The mechanism for optimized photodegradation behavior and dramatically increased adsorption capacity are discussed based on analyses of the structural evolution, surface properties including the chemical state and surface charge, electrochemical performance and the yield/type of photogenerated species. Density functional theory (DFT) simulations were conducted to investigate the structural state, density of states (DOS) and electrostatic potential.

Improved photocatalytic oxidation of micropollutant in wastewater by solar light: assisted palladium-doped graphitic carbon nitride

The escalating global industrial expansion has led to the extensive release of organic compounds into water bodies, resulting in substantial pollution and posing severe threats to both human health and the ecosystem. Among common micropollutants, bisphenol A (MP-BA) has emerged as a significant endocrine-disrupting chemical with potential adverse effects on human health and the environment. This study aims to develop an efficient photocatalyst, specifically by incorporating palladium-doped graphitic carbon nitride (Pd@GCN), to eliminate MP-BA pollutants present in industrial wastewater. The examination of optical properties and photoluminescence indicates that incorporating Pd into GCN enhances the visible light absorption spectra, which extends beyond 570 nm, and accelerates the separation rate of electron-hole pairs. The photocatalytic degradation efficiency of MP-BA increases from 81.7 to 98.8% as the solution pH rises from 5.0 to 9.0. Moreover, Pd@GCN significantly improves the removal rate of MP-BA in wastewater samples, reaching an impressive 92.8% after 60 min of exposure to solar light. Furthermore, the Pd@GCN photocatalyst exhibits notable reusability over six cycles of MP-BA degradation, indicating its promising potential for the treatment of organic pollutants in wastewater under solar light conditions.

Methyl-terminated graphite carbon nitride with regulatable local charge redistribution for ultra-high photocatalytic hydrogen production and antibiotic degradation

Intramolecular-tailored graphite carbon nitride (g-C3N4) has great potential to greatly optimize the photo-response performance and carrier separation ability, but exquisite molecular structure engineering is still challenging. Firstly, a series of oxygen and terminal methyl moiety co-modified g-C3N4 (CNNx) has been systematically prepared by using N-Hydroxysuccinimide (HOSu) as a novel copolymerized precursor and urea. The density functional theory (DFT) calculations demonstrated that the presence of oxygen can lower the binding energy for the C-C bond to make the terminal modification easier. The terminal methyl and Oxygen not only caused abundant alveolar defects to break the periodic symmetry but also acted as an electron-accepting platform to tune the local charge redistribution within g-C3N4 molecular. The synthesized CNNx (CNN25) achieved ultra-high photocatalytic activity and chemical stability under visible light toward antibiotic degradation (99% tetracycline, 92% doxycycline, 65% ofloxacin and 74% sulfathiazole degradation within 30 min) and hydrogen production (an apparent quantum efficiency of 2.10% at 400 nm). CNN25 also maintains good efficiency in surface water and groundwater. Moreover, the TC solution treated with CNN25 had hardly any harm to the growth of E. coli. We believe our findings will provide a facile and green strategy for the preparation of non-metallic modified g-C3N4.

Recyclable and flexible Bi(Ho3+-Yb3+)OBr/g-C3N4 composite porous fiber for efficient water purification and real-time temperature sensing

Herein, an electrospinning porous nanofiber with large specific surface area, excellent flexibility, remarkable tensile strength, and high stability of thermal degradation has been developed by loading Ho3+/Yb3+ co-doped BiOBr/g-C3N4 (BHY/CN) heterojunction photocatalysts on polyacrylonitrile (PAN) nanofibers. The optimized BHY/CN-2 nanofiber demonstrates outstanding photocatalytic activity for the degradation of 98.83% tetracycline (TC, 60 min) and 99.06% rhodamine B (RhB, 90 min) under simulated sunlight irradiation, and maintains a high level of reusability and recycling stability in three cycles. In addition, temperature monitoring of the catalytic degradation process can be feedback by (5F4, 5S2) → 5I8 and 5F5 → 5I8 radiation transitions of Ho3+ with excellent sensitivity. More importantly, the nanofiber luminescence performance is enhanced by the doping of g-C3N4, which maintain the effective upconversion luminescence properties even in water, providing a reliable reference for real-time monitoring and feedback of the operating temperature, and further expanding the application fields of photocatalysts.

Synergistic visible light assisted photocatalytic degradation of p-chlorophenol and rifampicin from aqueous solution using a novel g-C3N4 quantum dots incorporated α-MoO3 nanohybrid - Mechanism, pathway and toxicity studies

In this work, a simple g-C3N4 quantum dots enriched MoO3 nanohybrid was formulated for the synergistic photocatalytic degradation of an industrially active organic pollutant, p-chlorophenol (PCP) and a widely prescribed antibiotic, rifampicin (RIF). The nanohybrid was synthesised via a facile ultrasonic assisted hydrothermal method and characterized using various characterization analysis. The efficient Z-scheme charge transfer of the nanohybrid resulted in the elimination of 98% PCP and 89% RIF under visible light with a rate constant of 0.012 and 0.006 min-1 respectively. The photocatalysis was attributed to the formation of both hydroxyl (OH•) and superoxide (O2•-) radicals in the resulting nanohybrid. The intermediates formed in the course of reaction were estimated through gas chromatography-mass spectroscopy/mass spectroscopy (GC-MS/MS) analysis and a suitable degradation pathway was constructed. The structural stability and reusability of the nanohybrid was affirmed through X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analysis to outweigh the industrial potential of the catalyst, with 85% PCP and 80% RIF removal efficiency after six cycles of degradation. In addition, the mineralization of the pollutants was confirmed by total organic carbon analysis. Further, the toxicity of the drug and the formed intermediates was determined using ecological structure activity relationships (ECOSAR) software. On the whole, this work provides an excellent insight for the development of environment-friendly materials in a large scale for the degradation of water-based pollutants.

Graphitic carbon nitride metal-free photocatalyst for the simultaneous removal of emerging pharmaceutical pollutants in wastewater

The presence of pharmaceutical pollutants in water has emerged as a significant public health concern due to their potential adverse impacts, including the development of antibiotic resistance. Consequently, advanced oxidation processes based on photocatalysis have garnered considerable attention for treating pharmaceutical contaminants in wastewater. In this study, graphitic carbon nitride (g-CN), a metal-free photocatalyst, was synthesized by the polymerization of melamine and assessed as a potential candidate for the photodegradation of acetaminophen (AP) and carbamazepine (CZ) in wastewater. Under alkaline conditions, g-CN demonstrated high removal efficiencies of 98.6% and 89.5% for AP and CZ, respectively. The relationships between degradation efficiency and catalyst dosage, initial pharmaceutical concentration, and photodegradation kinetics were investigated. Increasing the catalyst dose facilitated the removal of antibiotic contaminants, with an optimum catalyst dose of 0.1 g, achieving a photodegradation efficiency of 90.2% and 82.7% for AP and CZ, respectively. The synthesized photocatalyst removed over 98% of AP (1 mg/L) within 120 min, with a rate constant of 0.0321 min-1, 2.14 times faster than that of CZ. Quenching experiments revealed that g-CN was active under solar light and generated highly reactive oxidants such as hydroxyl (•OH) and superoxide (•O2-). The reuse test confirmed the good stability of g-CN for treating pharmaceuticals during three repeated cycles. Finally, the photodegradation mechanism and environmental impacts were discussed. This study presents a promising approach for treating and mitigating pharmaceutical contaminants in wastewater.

Polyaniline/g-C3N4/Bi2O3/Ti photoanode for visible light responsive photocatalytic fuel cell degradation of rhodamine B and electricity generation

In order to develop efficient photoanode to improve the performance of visible light responsive photocatalytic fuel cell (PFC), in this work, polyaniline/g-C₃N₄/Bi₂O₃/Ti photoanode was successfully prepared using silica-sol drop coating method, and assembled with Cu cathode to construct PFC to decompose rhodamine B and generate electricity simultaneously. The degradation rate, maximum photocurrent density and maximum power density of this PFC were 91.23%, 0.086 mA cm^-2 and 4.78 μW cm^-2, respectively, which were 1.4 and 1.8 times, 2.4 and 4.5 times, and 1.9 and 7.3 times those of the corresponding values of the PFCs with g-C₃N₄/Bi₂O₃/Ti and Bi₂O₃/Ti photoanodes, respectively. This is attributed to the type II heterojunction structure formed among polyaniline, g-C₃N₄ and Bi₂O₃ in the polyaniline/g-C₃N₄/Bi₂O₃/Ti photoanode. Among them, polyaniline has π-π conjugated structure, which can rapidly transfer the electronic charge between g-C₃N₄ and Bi₂O₃, thus enhancing the separation efficiency of photo-generated e^--h⁺ pairs spatially and reducing their recombination, extending the visible light response wavelength of the photocatalyst, and finally improving its photocatalytic properties. This study can provide significant reference for the research of Bi₂O₃-based visible light responsive PFC.

Heterostructured 2D/2D ZnIn2S4/g-C3N4 nanohybrids for photocatalytic degradation of antibiotic sulfamethoxazole and photoelectrochemical properties

In recent years, antibiotic drugs have been extensively used owing to increased industrial growth, and this has created issues related to drinking water and a green environment. Different techniques have been used to resolve these issues, among which heterogeneous photocatalysis has been widely explored for the elimination of toxic compounds from wastewater resources. In this study, ZnIn₂S₄, g-C₃N₄, and ZnIn₂S₄/g-C₃N₄ hybrid heterostructured composites are synthesized via hydrothermal method and used these (i) for the removal of antibiotic sulfamethoxazole pollutant and (ii) photoelectrochemical water oxidation. The nanomaterials were characterized using X-ray diffraction, Scanning electron microscopy, transmission electron microscopy, and UV-vis spectroscopy. The developed hybrid heterostructured composites were able to degrade sulfamethoxazole pollutants as well as offer improved photoelectrochemical properties compared to pristine samples. The catalytic performance of the materials developed under visible light irradiation was greatly improved for the degradation of the antibiotic drug up to 89.4% in 2 h. Moreover, the hybrid heterostructured photoelectrode showed a better photocurrent density (8.68 mA/cm²) and exhibited ∼19.2 and 29.9 times greater photocurrent density than the pristine photoelectrodes. Such a considerably increased catalytic activity was attributed to the active separation of charge carriers and transmission. The study offers an innovative approach to develop effective catalysts, and for the degradation of sulfamethoxazole as well as the PEC properties for hydrogen production.

Boosted photocatalytic performance of OVs-rich BiVO4 hollow microsphere self-assembled with the assistance of SDBS

In this study, monoclinic phase bismuth vanadate (BiOV₄) photocatalyst with unique hollow microsphere morphology was successfully prepared by a hydrothermal method in the existence of sodium dodecyl benzene sulfonate (SDBS). The prepared photocatalysts were characterized by X-ray diffraction (XRD), scanning electron (SEM) and X-ray photoelectron spectrometer (XPS) and UV-vis diffuse reflectance spectroscopy (UV-vis DRS). Experimental results show that SDBS definitely changes the microstructure of BiVO₄, which is allocated to the template role of SDBS in the preparation process. Moreover, the hydrothermal treatment time is also of crucial importance in affecting the structure and morphology of the photocatalysts, and the optimal hydrothermal treatment time for the formation of hollow microsphere is 24 h. Furthermore, the feasible growth mechanism for hollow microsphere was elaborated. Enriched oxygen vacancies (OVs) are introduced into BiOV₄ prepared with SDBS, largely elevating the separation efficiency of photo-generated charges. Under visible light irradiation, the photocatalytic activities of BiOV₄ for destruction of rhodamine (RhB) were evaluated. The photocatalytic degradation rate constant of RhB on the 3SBVO is 2.23 times of that on the blank BiOV₄ as the mass ratio of SDBS/BiOV₄ is 3 %. Photocatalytic degradation mechanism of BiVO₄ toward detoxification of organic pollutants was presented.

Preparation and Properties of g-C3N4-TiO2 Cement-Based Materials Supported by Recycled Concrete Powder

In this paper, recycled concrete powder (RCP) is used as the carrier of g-C3N4-TiO2 instead of natural minerals. The prepared g-C3N4-TiO2/RCP composites were characterized by X-ray diffractometer, scanning electron microscope, infrared spectrometer, specific surface area analyzer, UV-visible spectrophotometer, and RhB solution degradation experiments. The results show that the rough, porous structure of RCP was beneficial to the stable load of g-C3N4-TiO2. Under the condition that the content of g-C3N4-TiO2 catalyst is constant, the agglomeration of g-C3N4-TiO2 can be reduced by using RCP as a carrier, thus improving its photocatalytic efficiency. Subsequently, g-C3N4-TiO2/RCP was loaded onto the surface of cement-based materials by coating bonding method to study its photocatalytic performance. It is found that the photocatalytic cement-based material has a similar degradation effect on the degradation of surface RhB as g-C3N4-TiO2/RCP in RhB solution. Our work may open up a new field for the recycling of RCP and provide new ideas for the development of photocatalytic cement-based materials.

Self-Assembled Synthesis of Porous Iron-Doped Graphitic Carbon Nitride Nanostructures for Efficient Photocatalytic Hydrogen Evolution and Nitrogen Fixation

In this study, Fe-doped graphitic carbon nitride (Fe-MCNC) with varying Fe contents was synthesized via a supramolecular approach, followed by thermal exfoliation, and was then used for accelerated photocatalytic hydrogen evolution and nitrogen fixation. Various techniques were used to study the physicochemical properties of the MCN (g-C₃N₄ from melamine) and Fe-MCNC (MCN for g-C₃N₄ and C for cyanuric acid) catalysts. The field emission scanning electron microscopy (FE-SEM) images clearly demonstrate that the morphology of Fe-MCNC changes from planar sheets to porous, partially twisted (partially developed nanotube and nanorod) nanostructures. The elemental mapping study confirms the uniform distribution of Fe on the MCNC surface. The X-ray photoelectron spectroscopy (XPS) and UV-visible diffuse reflectance spectroscopy (UV-DRS) results suggest that the Fe species might exist in the Fe³⁺ state and form Fe-N bonds with N atoms, thereby extending the visible light absorption areas and decreasing the band gap of MCN. Furthermore, doping with precise amounts of Fe might induce exfoliation and increase the specific surface area, but excessive Fe could destroy the MCN structure. The optimized Fe-MCNC nanostructure had a specific surface area of 23.6 m² g^-1, which was 8.1 times greater than that of MCN (2.89 m² g^-1). To study its photocatalytic properties, the nanostructure was tested for photocatalytic hydrogen evolution and nitrogen fixation; 2Fe-MCNC shows the highest photocatalytic activity, which is approximately 13.3 times and 2.4 times better, respectively, than MCN-1H. Due to its high efficiency and stability, the Fe-MCNC nanostructure is a promising and ideal photocatalyst for a wide range of applications.

Investigation of the photocatalytic and optical properties of the SrMoO4/g-C3N4 heterostructure obtained via sonochemical synthesis with temperature control

In this work, nanomaterials of the SrMoO₄/g-C₃N₄ heterostructure were synthesized in a single step by the sonochemical method with controlled temperatures. Structural and morphological investigations indicate the formation of heterojunctions, revealing the presence of g-C₃N₄ (CN) in the heterostructures and an interface region between the phases. Optical analyzes show broadening of the wavelength absorption range and a decrease in the photoluminescence (PL) intensity of the heterojunctions compared to the CN emission spectrum, proving a decrease in the recombination of the photogenerated charges. The results of the photocatalytic tests indicate that the insertion of CN promoted photocatalytic degradation of the Methylene Blue (MB), Rhodamine B (RhB) and Crystal Violet (CV) organic contaminants, up to 99.58%, 100% and 98.65%, respectively. The mixture of dyes used and reuse cycles was performed to analyze the applicability of the compounds in a real situation.

Interfacial engineering of novel inorganic-organic β-Ga2O3/COF heterojunction for accelerated charge transfer towards artificial photosynthesis

Semiconductor-based solar-driven CO₂ to fuels has been widely reckoned as an ingenious approach to tackle energy crisis and climate change simultaneously. However, the high carrier recombination rate of the photocatalyst severely dampens their photocatalytic uses. Herein, an inorganic-organic heterojunction was constructed by in-situ growing a dioxin-linked covalent organic framework (COF) on the surface of rod-shaped β-Ga₂O₃ for solar-driven CO₂ to fuel. This novel heterojunction is featured with an ultra-narrow bandgap COF-318 (absorption edge = 760 nm), which is beneficial for fully utilizing the visible light spectrum, and a wide bandgap β-Ga₂O₃ (absorption edge = 280 nm) to directional conduct electrons from COF to reduce CO₂ without electron-hole recombination occurred. Results showed that the solar to fuels performance over β-Ga₂O₃/COF was much superb than that of COF. The optimized Ga₂O₃/COF achieved an outstanding CO evolution rate of 85.8 μmol h^-1·g^-1 without the need of any sacrificial agent or cocatalyst, which was 15.6 times more efficient than COF. Moreover, the analyses of photoluminescence electrochemical characterizations and density functional theory (DFT) calculations revealed that the fascinate construction of β-Ga₂O₃/COF heterojunction significantly favored charge separation and the directional transfer of photogenerated electrons from COF to β-Ga₂O₃ followed by CO₂. This study paves the way for developing effective COF-based semiconductor photocatalysts for solar-to-fuel conversion.

A review on the progress of the photocatalytic removal of refractory pollutants from water by BiOBr-based nanocomposites

Organic matters from various sources such as the manufacturing, agricultural, and pharmaceuticals industries is continuously discharged into water bodies, leading to increasingly serious water pollution. Photocatalytic technology is a clean and green advanced oxidation process, that can successfully decompose various organic pollutants into small inorganic molecules such as carbon dioxide and water under visible light irradiation. Bismuth oxybromide (BiOBr) is an attractive visible light photocatalyst with good photocatalytic performance, suitable forbidden bandwidth, and a unique layered structure. However, the rapid combination of the electron-hole pairs generated in BiOBr leads to low photocatalytic activity, which limits its photocatalytic performance. Due to its unique electronic structure, BiOBr can be coupled with a variety of different functional materials to improve its photocatalytic performance. In this paper, We present the morphologically controllable BiOBr and its preparation process with the influence of raw materials, additives, solvents, synthesis methods, and synthesis conditions. Based on this, we propose design synthesis considerations for BiOBr-based nanocomplexes in four aspects: structure, morphology and crystalline phase, reduction of electron-hole pair complexation, photocorrosion resistance, and scale-up synthesis. The literature on BiOBr-based nanocomposites in the last 10 years (2012-2022) are summarized into seven categories, and the mechanism of enhanced photocatalytic activity of BiOBr-based nanocomposites is reviewed. Moreover, the applications of BiOBr-based nanocomposites in the fields of degradation of dye wastewater, antibiotic wastewater, pesticide wastewater, and phenol-containing wastewater are reviewed. Finally, the current challenges and prospects of BiOBr-based nanocomposites are briefly described. In general, this paper reviews the construction of BiOBr-based nanocomposites, the mechanism of photocatalytic activity enhancement and its research status and application prospects in the degradation of organic pollutants.

A novel Fe/Mo co-catalyzed graphene-based nanocomposite to activate peroxymonosulfate for highly efficient degradation of organic pollutants

A novel 3D α-FeOOH@MoS₂/rGO nanocomposite was successfully fabricated by a simple in situ hydrothermal method. It is a highly efficient heterogeneous catalyst in activation of peroxymonosulfate (PMS) for rapid degradation of rhodamine B (RhB), with 99.9% of RhB removed within 20 min. The introduction of rGO contributes to uniform dispersion and sufficient contact of α-FeOOH and MoS₂ nanosheets. Highly active Mo(IV) enhances the reduction of Fe(III), improves Fe(III)/Fe(II) conversion and promotes the generation of O₂1, which ensures an improved catalytic activity. MoS₂/rGO hybrid can effectively solve the problem of material reunion and make α-FeOOH exhibit excellent catalytic performance. The α-FeOOH@MoS₂-rGO/PMS system is a co-catalytic system based on the active components of α-FeOOH and MoS₂. The main reactive oxygen species in the α-FeOOH@MoS₂-rGO/PMS system are O₂1, SO₄^.- and ⋅O₂^-, which contribute to a high reactivity over a wide range of pH (5-9). Besides, this system is highly resistant to anions (Cl^-, SO₄^2-) and natural organic matter (humic acid), and can be widely used for degradation of common organic pollutants. The α-FeOOH@MoS₂/rGO is a promising Fenton-like catalyst for refractory organic wastewater treatment.

Constructing Ni4/Fe@Fe3O4-g-C3N4 nanocomposites for highly efficient degradation of carbon tetrachloride from aqueous solution

Catalytic hydrodechlorination is one of the most potential remediation methods for chlorinated organic pollutants. In this study, Ni₄/Fe@Fe₃O₄-g-C₃N₄ (NFFOCN) nanocomposites were synthesized for carbon tetrachloride (CT) removal and characterized by SEM, XPS and FTIR. The characterization results demonstrated that the special functional groups of g-C₃N₄, especially NH groups, effectively alleviated the aggregation of nanoparticles. In addition, the C and N groups of g-C₃N₄ enhanced the catalytic dechlorination of CT by providing binding sites. The experimental results showed that NFFOCN could effectively remove CT over a wide initial pH range of 3-9, and the CT removal efficiency reached 94.7% after 35 min with only 0.15 g/L of NFFOCN at pH 5.5. The Cl^-, SO₄^2-, and HCO₃^- promoted the removal of CT, while HA and NO₃^- had the opposite effect. Furthermore, good sequential CT removal by NFFOCN nanocomposites was observed, and the CT removal efficiency reached 77.3% after four cycles. Based on the identification of products, a possible degradation pathway of CT was proposed. Moreover, the main mechanisms regarding CT removal included the direct reduction of nZVI (about 40.51%), adsorption (around 34.79%), and hydrodechlorination of CT by Ni⁰ using H₂ (about 19.40%).

Sunlit expeditious visible light-mediated photo-fenton degradation of ciprofloxacin by exfoliation of NiCo2O4 and Zn0·3Fe2·7O4 over g-C3N4 matrix: A brief insight on degradation mechanism, degraded product toxicity, and genotoxic evaluation in Allium cepa

Pharmaceutical pollutant in the environmental water bodies has become a major concern, which causes adverse effect to aquatic entities. This study provides an incisive insight on the photocatalytic degradation of ciprofloxacin (CIP) and the development of rationally engineered g-C3N4-NiCo2O4-Zn0.3Fe2·7O4 nanocomposite for boosted photocatalytic performance under visible light irradiation. The g-C3N4-NiCo2O4-Zn0.3Fe2·7O4 nanocomposite was synthesized via ultrasonication-assisted hydrothermal method. The characterization of the as-prepared material was evaluated by XPS, SEM, HR-TEM, PL, FT-IR, EIS, ESR, XRD, BET, and UV-Vis DRS techniques. Furthermore, the effect of catalytic dosage, drug dosage, and pH changes was explored, where g-C3N4-NiCo2O4-Zn0.3Fe2·7O4-10% unveiled excellent visible light photo-Fenton degradation of 92% for CIP at 140 min. The hydroxyl radicals (OH.) served as the predominant radical species on the photodegradation of CIP, which was confirmed by performing a radical scavenging test. Furthermore, the degradation efficiency was determined by six consecutive cycle tests, where the nanomaterial exhibited excellent stability with 98.5% reusable efficiency. The degradation of CIP was further scrutinized by GC-MS analysis, where the degraded intermediate products and the possible pathway were elucidated. The degraded product toxicity was determined by ECOSAR program, where the degraded products haven't exhibited any considerable toxic effects. In addition, the genotoxicity of the nanomaterial was determined by treating them with root tips of A. cepa, where it was found to be non-toxic. Here, the prepared g-C3N4-NiCo2O4-Zn0.3Fe2·7O4 nanocomposite (CNZ NCs) shows eco-friendly and excellent photo-Fenton activity for environmental applications.

Recent Progress on Photoelectrochemical Water Splitting of Graphitic Carbon Nitride (g−CN) Electrodes

Graphitic carbon nitride (g−CN), a promising visible-light-responsive semiconductor material, is regarded as a fascinating photocatalyst and heterogeneous catalyst for various reactions due to its non-toxicity, high thermal durability and chemical durability, and “earth-abundant” nature. However, practical applications of g−CN in photoelectrochemical (PEC) and photoelectronic devices are still in the early stages of development due to the difficulties in fabricating high-quality g−CN layers on substrates, wide band gaps, high charge-recombination rates, and low electronic conductivity. Various fabrication and modification strategies of g−CN-based films have been reported. This review summarizes the latest progress related to the growth and modification of high-quality g−CN-based films. Furthermore, (1) the classification of synthetic pathways for the preparation of g−CN films, (2) functionalization of g−CN films at an atomic level (elemental doping) and molecular level (copolymerization), (3) modification of g−CN films with a co-catalyst, and (4) composite films fabricating, will be discussed in detail. Last but not least, this review will conclude with a summary and some invigorating viewpoints on the key challenges and future developments.

Research progress of photocatalysis for algae killing and inhibition: a review

The healthy development of biodiversity has been threatened frequent water eutrophication. In recent years, photocatalytic technology, which has attracted researchers' attention, not only showed increasing potential in the field of organic pollutant degradation, but also many kinds of photocatalysts were used in the field of red tide pollution control at present, which showed superior ability to inactivate harmful algae and degrade algal toxins. Researches have also explored the mechanisms of photocatalytic algae inhibition. In this study, the current research progress in the field of photocatalytic algae inhibition was systematically discussed from several aspects, such as common types of photocatalysts, modification methods of photocatalysts, types of tested algae for photocatalytic algae inhibition, and action mechanism of inactivated algae cells, so as to provide a certain theoretical basis for further application research of photocatalysts in the field of algae removal in the later period.

Enhanced visible light photocatalytic activity of the needle-like SrMoO4 decorated g-C3N4 heterostructure for degradation of tetracycline

Photocatalytic mechanism diagram of SrMoO4/g-C3N4.