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The surface-enhanced Raman scattering (SERS) performance and photocatalytic degradation of dye molecules absorbed on Ag nanoparticle-decorated ZnO microrods are investigated at 20 and 50 °C. The role of temperature in the mechanism is elucidated. This work provides insight into the optimization of temperature-dependent plasmon-induced catalysis using similar materials. [ABSTRACT FROM AUTHOR]

In this paper, a NiAl-LDH with the characteristic structure of a hydrotalc-like compound was applied as a carrier in a two-step hydrothermal process, and a MnCdS/In2S3/NiAl-LDH composite material was successfully prepared by loading MnCdS and In2S3 on the flower spherical-like surface of NiAl-LDH. The combination of NiAl-LDH with In2S3 and MnCdS made the band gap smaller and the light absorption range larger, thus increasing the utilization rate of light. 50% MnCdS/In2S3/NiAl-LDH composites had the best photoinduced charge separation and highest surface enrichment of photogenerated electrons. In the degradation experiment of crystal violet (CV), 50% MnCdS/In2S3/NiAl-LDH composites showed superior photocatalytic degradation efficiency (>98.5%) under full spectrum light. Furthermore, the applicability and universality of photocatalysts were studied by observing the degradation of CV by MnCdS/In2S3/NiAl-LDH composites under different conditions. In addition, the composites showed excellent hydrogen production capacity in the photolysis of water, in which hydrogen production within 8 hours was about 7661.51 μmol g−1. By combining the results of active species capture experiments, density functional theory (DFT) calculations and photoelectrochemical experiments, the possible mechanism of double S-scheme heterojunction photocatalysis among NiAl-LDH, In2S3 and MnCdS was inferred, which is one of the main reasons for the enhancement of photocatalytic activity. [ABSTRACT FROM AUTHOR]

Metal oxide composites with graphene/graphene oxide have increasingly gained popularity in enhancing the photocatalytic degradation of several existing harmful dyes. Moreover, identifying the role of carbon networks and their interactions in composite formation would assist in the design and development of photocatalysts. In the present study, we investigated the role of carbon networks in improving photocatalytic properties. Electronic structure analysis of cobalt oxide–graphene (C2)/graphene oxide (C3) nanocomposites using XAS suggested possible charge transfer from cobalt oxide nanoparticles to the carbon network during composite formation. The photocatalytic degradation of C3 towards phenol dye (1 × 10−3 M) was >50% and improved the degradation rate with k = 0.231 h−1.In the quest to understand the mechanism unfolding on its surface, in situ XAS under UV–visible irradiation was performed, which shed light on delayed excitonic recombination in the synthesized nanocomposites. This enabled hydroxy radicals (˙OH) to play a preeminent role in the cleavage of the phenol ring and its intermediaries. Based on these observations, a detailed mechanism for charge transfer occurring during nanocomposite formation and the mechanism involved in the enhanced photocatalytic activity of the nanocomposite photocatalyst towards phenol degradation under the influence of UV–visible irradiation are discussed. [ABSTRACT FROM AUTHOR]

In this research, Sr-doped hydroxyapatite, HAp and NiO nanoparticles were used to produce a novel nanocomposite, Sr-doped HAp/NiO. Various analytical and instrumentation techniques such as FTIR, PXRD, UV-DRS, SEM, TEM, and XPS were used to characterize the as synthesized composite material. The nanocomposite acts as an efficient photocatalyst and is able to degrade Congo red (CR) dye up to 95.6% within 40 min under solar light irradiation without any kind of external additive. The HR LC–MS spectrum was recorded to determine the degradation products of the chosen organic dye. Furthermore, the as prepared nanocatalyst also effectively reduced 98.7% of carcinogenic Cr(VI) to Cr(III) within just 10 min. In order to propose the photocatalytic mechanism and to detect the active radicals present, a radical trapping experiment was conducted. As an appealing photocatalyst for wastewater treatment and reduction of toxic chemicals, the research concluded with a methodical and cost-effective process for producing the Sr-doped HAp/NiO nanocomposite. [ABSTRACT FROM AUTHOR]

This study presents the synthesis of a new nanocomposite named Zn3V2O8/hydroxyapatite (ZnV/HAP) to assess its photocatalytic efficiency for degrading Congo red dye (CR) under visible light. The nanocomposite was analyzed using various techniques, including FT-IR, XRD, UV-vis DRS, SEM, TEM, EDAX, XPS, and BET analysis. The photocatalyst's performance was enhanced by a shift in its band gap to 1.7 eV, compared to similar materials. ZnV/HAP exhibits superior photocatalytic performance compared to ZnV particles. The rate constant for the degradation of CR by ZnV/HAP was determined to be 0.0063 min−1. The degrading efficiency of the ZnV/HAP composite is 94%. The enhanced charge separation in the ZnV/HAP composite is attributed to the strong contacts between the interfacial surfaces, which are responsible for their higher activity. A method was found to facilitate this heightened activity, with hydroxyl and superoxide radicals serving as crucial reactive species that significantly contribute to the photocatalytic process. The phytotoxicity investigation conducted on Vigna radiata plants demonstrated the photocatalytic effectiveness of the ZnV/HAP combination. In addition, the deteriorated CR dye solution exhibited a color removal efficiency of 94.62% for total organic carbon (TOC) and 92.86% for chemical oxygen demand (COD). The findings demonstrate that the synthesized ZnV/HAP is a viable substitute for visible-light-driven photocatalysts. Furthermore, the antimicrobial efficacy of ZnV/HAP was assessed against Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Aspergillus niger, demonstrating remarkable antibacterial and antifungal properties comparable to the positive control medication. [ABSTRACT FROM AUTHOR]

A BODIPY-containing conjugated microporous polymer (CMP, LBFD-1) was modified with calixarene to develop a hydrophilic CMP (LBFD-2) with broader absorption extending to the near-infrared-II region. LBFD-2 exhibited an H2O2 production rate of 2.14 mmol g−1 h−1 in the air without any sacrificial agents. The removal efficiency (η) of LBFD-2 towards methylene blue and rhodamine B reached >99.5% within 20 and 40 min in light. LBFD-2 can withstand diverse environmental changes, showing excellent reusability and potential for practical applications in real-water systems. [ABSTRACT FROM AUTHOR]

The residue of antibiotics and various pollutants has led to an urgent issue in environmental pollution control. In this study, we constructed an S-scheme P-TiO2@Zn-MOF heterojunction by self-assembling phosphonate-based MOFs on mesoporous phosphate-TiO2 beads. Compared to monomers, the P-TiO2@Zn-MOF2.0 heterojunction exhibits significantly higher photocatalytic activity for the photo-oxidative degradation of ciprofloxacin (97.2% in 60 min) and tetracyclic (TC) (94.5% in 100 min) and the photo-reduction of Cr(VI) (92.7% in 60 min) under simulated sunlight. Experimental results and calculations revealed the effective separation and transfer of photogenerated carriers at the P-TiO2@Zn-MOF2.0 S-scheme heterojunction interface, enabling the formation of highly active superoxide and hydroxyl radicals. Furthermore, the hybrid maintained excellent Cr(VI) photoreduction performance after recycling tests in actual electroplating industry wastewater at a strongly acidic pH. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal Chemical Society Reviews. It includes a variety of articles on topics such as oxidative degradation of plastics, atmospheric water harvesting, biofabrication with microbial cellulose, and electrolysis for fuels and chemicals production. The journal aims to connect the world with the chemical sciences and is published by The Royal Society of Chemistry. The document also mentions approved training courses offered by the society for professional development. [Extracted from the article]

Oxidative degradation is a powerful method to degrade plastics into oligomers and small oxidized products. While thermal energy has been conventionally employed as an external stimulus, recent advances in photochemistry have enabled photocatalytic oxidative degradation of polymers under mild conditions. This tutorial review presents an overview of oxidative degradation, from its earliest examples to emerging strategies. This review briefly discusses the motivation and the development of thermal oxidative degradation of polymers with a focus on underlying mechanisms. Then, we will examine modern studies primarily relevant to catalytic thermal oxidative degradation and photocatalytic oxidative degradation. Lastly, we highlight some unique studies using unconventional approaches for oxidative polymer degradation, such as electrochemistry. [ABSTRACT FROM AUTHOR]

Over the past decades, the field of organic solar cells (OSCs) has witnessed a significant evolution in materials chemistry, which has resulted in a remarkable enhancement of device performance, achieving efficiencies of over 19%. The photoactive layer materials in OSCs play a crucial role in light absorption, charge generation, transport and stability. To facilitate the scale-up of OSCs, it is imperative to address the photostability of these electron acceptor and donor materials, as their photochemical degradation process remains a challenge during the photo-to-electric conversion. In this review, we present an overview of the development of electron acceptor and donor materials, emphasizing the crucial aspects of their chemical stability behavior that are linked to the photostability of OSCs. Throughout each section, we highlight the photochemical degradation pathways for electron acceptor and donor materials, and their link to device degradation. We also discuss the existing interdisciplinary challenges and obstacles that impede the development of photostable materials. Finally, we offer insights into strategies aimed at enhancing photochemical stability and discuss future directions for developing photostable photo-active layers, facilitating the commercialization of OSCs. [ABSTRACT FROM AUTHOR]

In this work, based on the electrostatic adsorption theory, a direct Z-scheme NH2-UiO-66/BiOCl composite photocatalyst was prepared by a one-step solvothermal method with NH2-UiO-66 embedded on the smooth surface of flower-like BiOCl without additional chlorine source to form a close contact interface. The photocatalytic degradation of tetracycline hydrochloride (TCH) of 1.0-NH2-UiO-66/BiOCl(1.0-NUBC) prepared under simulated sunlight was 1.63 times and 78.84 times that of pure BiOCl and pure NH2-UiO-66, respectively. The reason for the enhanced photocatalytic performance may be that electrostatic adsorption promotes the homogeneous and orderly synthesis of heterogeneous structures, significantly increasing the ratio of NH2-UiO-66/BiOCl surface, which not only improves the visible light response range but also promotes the formation of the interface electric field between NH2-UiO-66 and BiOCl interface. The separation and transfer of the photogenerated electron–hole pairs are greatly promoted. Therefore, this study provides an effective way for the synthesis of BiOCl/MOF composites and has a good application prospect. [ABSTRACT FROM AUTHOR]

Bi5O7I doped with Zn2+ (Zn2+/Bi5O7I) was prepared using a precipitation calcination method. Its photocatalytic activity was improved by adjusting the band gap of Bi5O7I, and its photocatalytic performance was evaluated by degrading RhB. The experimental results showed that Zn2+/Bi5O7I-8 had the highest photodegradation efficiency, and the degradation rate for RhB after exposure to light for 30 minutes was 91% and reached 100% in 60 minutes. The degradation rate constant k of Zn2+/Bi5O7I-8 reached 0.10813 min−1, which is 13 times more than that of Bi5O7I. As a result of Zn2+ being added into Bi5O7I, the band gap of Zn2+/Bi5O7I became narrower than that of Bi5O7I, and the photogenerated electrons and holes were successfully prevented from recombining; therefore, the photocatalytic activity of Zn2+/Bi5O7I was higher than that of Bi5O7I. After four rounds of photocatalytic experiments, the photocatalytic efficiency of Zn2+/Bi5O7I-8 remained high. The composition and microstructure of the materials were characterized using XRD, FTIR, XPS, SEM, and TEM. The optical properties and degradation mechanism of the material were investigated using DRS, PL, photocurrent response, and active substance capture experiments. A suggested mechanism for the photocatalytic degradation of RhB is presented. [ABSTRACT FROM AUTHOR]

The current work aims to generate multifunctional MOFs by incorporating a well-known inorganic motif, a trinuclear Cu-pyrazolate [Cu3(μ3-OH)(μ-Pyz)3] (T-CuP) unit, as a node of the network. Accordingly, we report herein the synthesis and properties of five new compounds using five V-shaped dicarboxylic acids as auxiliary ligands. The structural features are consistent with the theme of grafting T-CuP units as nodal points of architectures whose chassis are primarily made of bent acids. V-shaped acids also induce a helical nature inside resulting frameworks. Beside their structural and physical features, T-CuP unit-based MOFs also vindicate our thematic approach of the trinuclear Cu-pyrazolate unit imparting specific physicochemical properties, such as magnetic, electrical, and catalytic properties, to resultant MOFs. The MOFs show excellent catalytic properties in reducing 4-nitrophenol, which could be attributed to the porous nature of the network along with the presence of metal centres with unsaturated coordination within the T-CuP unit. Furthermore, efficient photocatalytic degradation of harmful organic dyes confirms their importance for environmental remediation. The presence of a T-CuP unit and various functional groups also make some of the MOFs suitable candidates for electrical applications, which is indeed manifested in encouraging proton conductivity. Finally, the potential of current MOFs, fitted with a magnetically important trinuclear Cu-pyrazolate motif, as magnetic materials has also been thoroughly investigated. [ABSTRACT FROM AUTHOR]

The construction of Z-scheme heterojunctions is still a challenge. Structure tailoring and energy band engineering of metal–organic frameworks (MOFs) permit the rational design and fabrication of Z-scheme MOF/graphene oxide (GO) heterojunctions to enhance photocatalytic performance. Herein, a novel Z-scheme Zn-MOF/GO heterojunction as an environmentally friendly, reusable, and highly efficient visible-light-induced photocatalyst for methylene blue (Mb) decoloration and/or Cr(VI) reduction was synthesized. The Zn-MOF/GO composite displayed much higher photodegradation performance than pure Zn-MOF. Besides, the photocatalytic performance of composites is related to the amounts of GO, and Zn-MOF/GO(15%) showed the best activity. Specifically, Zn-MOF/GO(15%) presented 92.6% Mb decoloration, 98.8% Cr(VI) reduction, and the simultaneous removal of Mb (87.9%) and Cr(VI) (99.8%) with good stability. The improved performance for Zn-MOF/GO(15%) can be due to the formation of the Z-scheme heterojunction and built-in electric field, which can not only promote the photogenerated electron–hole separation and transfer, but also broaden the spectrum of light absorption. Furthermore, the improved plausible photodegradation mechanism of Zn-MOF/GO(15%) was provided, and e−, h+ and ·OH were the primary reactive species during the photodegradation reactions. [ABSTRACT FROM AUTHOR]

In this work, a new d10-configuration based Cd(II) coordination polymer (CP) with the formula [Cd2(CH3COO)2(bimb)2]·2ClO4 (1) have been synthesized using 4,4′-bis(imidazolyl)biphenyl (bimb) ligand and characterized. Single-crystal X-ray analysis reveals that the CP forms a 2D layer connected to a 3D supramolecular framework with weak packing interactions between benzyl and imidazolyl rings. CP 1 has been used as a photoluminescent sensor and a photocatalyst for the photodegradation of antibiotics, in particular nitrofurantoin (NFT). Sensing experiments indicate that 1 can selectively detect nitrofurantoin with a limit of detection of 0.025 μM, whereas when employed as a photocatalyst, CP 1 can photodecompose NFT up to 91.83% in a time span of 20 min. The decline in the photoluminescence intensity of CP 1 in the presence of NFT and the photocatalytic mechanism are addressed using theoretical calculations. [ABSTRACT FROM AUTHOR]

Advanced oxidative process is an efficient method to photocatalytically degrade the effluent pollution by organic dyes with a suitable catalyst. Photocatalysts with a heterojunction not only improve the excitation efficiency of the catalyst in the presence of light by broadening the wavelength range of absorption but also reduce the rate of recombination. ZnO and TiO2 were successfully synthesized in this study via solution combustion synthesis. Wurtzite ZnO was grown along with anatase TiO2 to create a heterojunction of ZnO–TiO2, and Co loading was carried out to improve the rate of electron transfer between the heterojunction for enhanced photocatalytic activity. The photogenerated electrons are injected from the conduction band of ZnO to TiO2via Co to create ˙O2− and holes from TiO2 to form OH˙, which help to degrade alizarin S. The detailed photocatalytic experiment confirmed Co/ZnO–TiO2 as an extremely efficient catalyst, which shows the complete degradation of the dye alizarin S in just 40 minutes under UV light illumination. [ABSTRACT FROM AUTHOR]

Herein, a series of N-doped Ti3C2/porous g-C3N4 composites are ultrasonically prepared from N-doped Ti3C2 and porous g-C3N4 under N2 atmosphere. The structure, morphology, and optical characteristics of the as-prepared composites are characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, UV-vis diffuse reflectance spectroscopy, etc. Moreover, photocatalytic measurements show that N-doped Ti3C2 is an excellent modifier for porous g-C3N4 to heighten its photocatalytic activity. Only 44.1% of rhodamine B can be degraded by the photocatalysis of pristine porous g-C3N4, while the photocatalytic degradation ratio of rhodamine B can reach up to 97.5% for the optimal N-doped Ti3C2 loading composites under visible light for 15 min. Moreover, the photocatalytic tests of N2 fixation confirm that the optimal composites show the highest production yield of NH4+ (11.8 μmol gcat−1 h−1), which is 2.11-folds more than that of porous g-C3N4 (5.6 μmol gcat−1 h−1). The reinforced photocatalytic properties are revealed to profit from the more photogenerated electrons and holes' separation, higher ability for light response, and more abundant active sites. This work develops the route for boosting the photocatalytic properties of porous g-C3N4 with N-doped Ti3C2. [ABSTRACT FROM AUTHOR]

A type II heterostructured BiVO4/MIL-88B(Fe) composite was successfully synthesised for the photocatalytic degradation of tetracycline hydrochloride (TC-HCl) by a simple hydrothermal method. Thin film materials avoid secondary pollution of powder materials. The samples were characterised by XRD, SEM, TEM, XPS, UV-Vis DRS, and PL. The samples were also characterised for their optoelectronic properties. 3-BV/MIL-88B(Fe) (3 mmol BiVO4) was the most effective catalyst for the degradation of TCHCl, achieving 92.1% removal at 75 min with a degradation rate constant of 22.79 x 10-3 min-1. Moreover, durability evaluation and TC-HCl degradation potential evaluation were also performed. We looked into how TC-HCl concentration, pH and ions affect the degradation results. In order to determine the active ingredients, experiments for trapping free radicals and EPR tests were performed. The results indicated that the main active species were h+ and OH. It is proposed that a reasonable type-II heterostructure can help to explain the photocatalytic mechanism. The current study creates a stable photocatalytic system by compositing electrocatalytic and photocatalytic materials to achieve efficient antibiotic degradation and provides a viable strategy for future applications. [ABSTRACT FROM AUTHOR]

Photocages, also known as photoactivated protective groups (PPGs), have been utilized to achieve controlled release of target molecules in a non-invasive and spatiotemporal manner. In the past decade, BODIPY fluorophores, a well-established class of fluorescent dyes, have emerged as a novel type of photoactivated protective group capable of efficiently releasing cargo species upon irradiation. This is due to their exceptional properties, including high molar absorption coefficients, resistance to photochemical and thermal degradation, multiple modification sites, favorable uncaging quantum yields, and highly adjustable spectral properties. Compared to traditional photocages that mainly absorb UV light, BODIPY-based photocages that absorb visible/near-infrared (Vis/NIR) light offer advantages such as deeper tissue penetration and reduced bio-autofluorescence, making them highly suitable for various biomedical applications. Consequently, different types of photoactivated protective groups based on the BODIPY skeleton have been established. This highlight provides a comprehensive overview of the strategies employed to construct BODIPY photocages by substituting leaving groups at different positions within the BODIPY fluorophore, including the meso-methyl position, boron position, 2,6-position, and 3,5-position. Furthermore, the application of these BODIPY photocages in biomedical fields, such as fluorescence imaging and controlled release of active species, is discussed. [ABSTRACT FROM AUTHOR]

A novel MIL-101(Fe)/ZnCrZr-LBMO heterojunction was successfully constructed and used for the removal of ciprofloxacin (CIP) in this work. The MIL-101(Fe)/ZnCrZr-LBMO composite exhibited significantly enhanced photocatalytic degradation activity, with reaction rates approximately 3.4 and 3.1 times faster than those observed with pristine MIL-101(Fe) and ZnCrZr-LBMO, respectively. The effect of different amounts of ZnCrZr-LBMO, sample pH, CIP concentration, inorganic cations, and anions on CIP removal was investigated, and the possible intermediates and degradation pathways of CIP were speculated. The·O2− radicals dominated CIP degradation, with minor contributions from 1O2, h+, and ·OH radicals. The composite exhibited high removal rates for CIP (94.7%), ofloxacin (86.8%), and tetracycline (96.3%), respectively, within 60 min of light irradiation, and excellent reusability, retaining over 85.1% CIP degradation rate after five cycles. Our work provides a new reference to construct highly efficient and easily recyclable MIL-101(Fe)/ZnCrZr-LBMO photocatalysts for the removal of antibiotic pollutants, promising advancements in real water treatment applications. [ABSTRACT FROM AUTHOR]

Photocatalytic degradation of pollutants is one of the most promising strategies for addressing environmental issues associated with wastewater from textile and other dyeing industries. Graphitic carbon nitride (g-C3N4) has emerged as a prospective visible-light photocatalyst in this field due to its various advantages. However, pristine g-C3N4 often exhibits limited activity. To enhance the performance of g-C3N4, alkali metal ion doped g-C3N4 was prepared using a simple one-step thermopolymerization method. Characterization and analysis of the samples revealed that the obtained doped photocatalysts exhibited enhanced visible-light photocatalytic degradation activity. This is attributed to the reduction in grain size, which provides more active sites, extended visible-light absorption, a reduced bandgap, and more efficient electron transfer. Notably, due to the optimal adjustment of the microstructure and electronic structure, K+ doped g-C3N4 demonstrated the highest photocatalytic performance with a degradation rate of 89.1%, significantly surpassing the efficiency of pristine g-C3N4 (72%). These results demonstrated that the approach of incorporating alkali metal ions into g-C3N4 has the potential for facilitating high-performance photodegradation for organic pollutant removal. [ABSTRACT FROM AUTHOR]

To overcome the drawbacks of traditional techniques for improving latent fingerprint (LFP) and biosensing applications, such as low sensitivity, high background interference, complicated setups, and poor universality, we developed Zn1−xEuxO (x = 0, 0.25, and 0.5) nanoparticles via a co-precipitation method. On diverse porous and non-porous surfaces, LFPs coated with optimized Zn1−xEuxO (x = 0, 0.25, and 0.5) nanoparticles exhibit clearly defined ridge patterns with good sensitivity and little background interference. The Tauc plot determined the band gap energy, which declines with increasing Eu doping and was found to be 3.04, 3 and 2.95 eV for x = 0, 0.25, and 0.5, respectively; the increase in Eu doping levels in the ZnO host lattice resulted in enhanced photoluminescence (PL) capabilities. The photocatalytic activity response was investigated using the organic methylene blue (MB) dye as the pollutant. The photocatalytic activity of the Eu-doped NPs exhibited a higher performance of 94.83% compared with undoped ZnO NPs. Our findings open up new possibilities for utilizing optimized Eu-doped ZnO nanoparticles in forensic research and in the MB dye degradation process. [ABSTRACT FROM AUTHOR]

The presence of antibiotics in aquatic systems poses a significant risk to both the ecological balance and human health. To address this issue, the development of advanced photocatalytic materials capable of efficiently treating antibiotic-contaminated wastewater is imperative. In this investigation, we successfully synthesized nitrogen–phosphorus co-doped carbon dots (NPCDs) modified (001) TiO2/Ti3C2Tx composites via a series of uncomplicated hydrothermal reactions, ensuring visible light responsivity. Comprehensive characterization of the composite photocatalysts was conducted using XRD, FT-IR, N2 adsorption, SEM, TEM, XPS, UV-Vis DRS, and PL techniques. Subsequently, the photocatalytic performance was assessed through the degradation of tetracycline hydrochloride (TC) and ceftiofur sodium solutions under visible light irradiation. The optimized composites exhibited remarkable photocatalytic degradation efficiencies of 93.4% and 75.5% for TC and ceftiofur sodium, respectively, under visible light, following quasi-primary kinetic behavior. Reactive free radical capture experiments highlighted the predominant roles of ˙O2− and ˙OH species in the photocatalytic degradation process. Additionally, we proposed plausible mechanisms governing photocatalytic degradation based on the obtained results. The heightened photocatalytic reactivity arises from the efficient transfer of photogenerated electrons through the NPCDs → TiO2 →Ti3C2Tx pathway, a mechanism that effectively facilitates the separation and transfer of photogenerated charge carriers. [ABSTRACT FROM AUTHOR]

Nanomaterials have attracted great interest in the field of photocatalytic degradation due to their larger specific surface area and efficient charge/mass transfer ability, which are beneficial for enhancing photocatalytic activity. However, the bandgap of photocatalysts would increase with the size reduction, weakening the photoabsorption ability. Thus the relationship between the size of catalysts and photoactivity should be balanced to achieve optimal photocatalytic performance. Herein, ultra-small CuWO4 nanoparticles (ca. 39 nm) with moderate oxygen vacancies (CuWO4–OVs) were synthesized by the cascade strategy (ligand confinement@fast calcination). The introduction of oxygen vacancies offset the deficiency of light absorption ability caused by the small size effect. Besides, oxygen vacancies could provide more reaction active sites, conducive to the adsorption and activation of dye molecules and H2O. Degradation experiments reveal that the optimized photocatalyst CuWO4–OVs 350 shows outstanding photocatalytic activity, and the removal ratio of methylene blue (MB) reaches over 90.26% in 70 min, exceeding that of pure CuWO4–air (37.66%). Additionally, the degradation performance of CuWO4–OVs 350 surpasses most of the other CuWO4-based photocatalytic systems. More importantly, the photocatalytic degradation activity of CuWO4–OVs 350 could remain at 88.26% even after five cycles, and high photostability was achieved. This work affords constructive inspiration for synergistic photoactivity enhancement and increase of catalyst reaction active sites to achieve eminent photocatalytic degradation performance. [ABSTRACT FROM AUTHOR]

Designing efficient, inexpensive, and stable photocatalysts to degrade organic pollutants and antibiotics has become an effective way for environmental remediation. In this work, we successfully performed in situ growth of CdS QDs on the surface of elliptical BiVO4 to try to show the advantage of the binary heterojuncted photocatalyst (BVO@CdS) for the photocatalytic degradation of tetracycline (TC). The In situ growth of CdS QDs can provide a large number of reactive sites and also generate a larger contact area with BiVO4. In addition, compared with mechanical composite materials, in situ growth can significantly reduce the energy barrier at the interface between BiVO4 and CdS, providing more channels for the separation and migration of photogenerated charge carriers, and further improving reaction activity. As a result, BVO@CdS-0.05 shows the best degradation efficiency, with a degradation rate of 88% after 30 min under visible light. The TC photodegradation follows a pseudo-second-order reaction with a dynamic constant of 0.472 min−1, which is 6.47 times that of pure BiVO4, 7.24 times that of pure CdS QDs and 2 times that of the mechanical composite. The degradation rate of BVO@CdS-0.05 decreases to 77.8% with a retention rate of 88.5% after four cycles, demonstrating excellent stability. Through liquid chromatography-mass spectrometry (LC-MS) analysis, two possible pathways for TC degradation are proposed. Through free radical capture experiments, electron spin resonance measurements, and photoelectrochemical comprehensive analysis, it is confirmed that BVO@CdS composites have constructed an efficient Z-scheme heterojunction via in situ growth, thereby highly enhancing the separation and transport efficiency of charge carriers. [ABSTRACT FROM AUTHOR]

In the realm of photocatalysis, effectively utilizing solar energy, especially the near-infrared (NIR) spectrum, presents substantial challenges. To tackle this issue, a novel composite of NaYF4:Yb3+/Er3+@Cu2O@MoS2@Fe3O4 (denoted as NYE@Cu2O@MoS2@Fe3O4) was ingeniously fabricated and assessed for the photodegradation of organic contaminants. By harnessing the distinct properties of upconversion materials, narrow bandgap semiconductors, and magnetic substances, the NYE@Cu2O@MoS2@Fe3O4 catalyst possesses a photodegradation rate of 92% for the rhodamine B dye under NIR light radiation, which is superior to NYE@Cu2O (50%) and NYE@Cu2O@MoS2 (85%). The enhanced performance in the near-infrared photocatalysis of NYE@Cu2O@MoS2@Fe3O4 is mainly attributed to the synergistic effect of various components, which promotes an increase in photo-induced carrier generation and facilitates their efficient transfer and energy utilization under NIR irradiation. This study provides a possible route for the near-infrared photocatalytic degradation of pollutants in areas with limited light or even dark conditions. [ABSTRACT FROM AUTHOR]

Three-dimensional iodoargentate hybrids [Co(en)3(Ag2I4)]n (1), [Fe(en)3(Ag2I4)]n (2) (en = ethylenediamine) and [Co(dien)2(Ag2I4)]n·nH2O (3) (dien = diethylenetriamine) were prepared in C2H5OH solvent via a one-step reaction under solvothermal conditions. In compounds 1 and 2, AgI4 tetrahedra were interlinked via corner-sharing to form a 3D α-Ag2I4 framework with interpenetrated channels with cross sectional dimensions of 8.071 Å × 9.039 Å and 9.039 Å × 9.039 Å. The AgI4 tetrahedra in compound 3 were connected via both corner- and edge-sharing into a 3D β-Ag2I4 framework with dimensions of 5.929 Å × 8.329 Å, and 8.329 Å × 9.910 Å. Compounds 1–3 showed sensitive photocurrent response under visible light irradiation with steady current densities in the range of 3.46–8.26 μA cm−2. These compounds were catalytically active during the photodegradation of crystal violet (CV), with degradation conversions of 72.2%, 91.5% and 80.1% after 105 min of light irradiation over compounds 1–3, respectively. [ABSTRACT FROM AUTHOR]

Restricted light absorption spectra in conjunction with intrinsic material instability present formidable challenges to the effective functionality of existing photocatalytic systems. As a viable alternative to conventional photocatalytic materials, hydrogen-bonded organic frameworks (HOFs) can form conjugated systems through coupling and stacking effects, which can effectively promote the rapid transfer of charge over a wide optical range and improve the stability and photocatalytic activity. Herein we employ a large conjugate system material based on cobalt phthalocyanine (HOF-CoPcTc) as a proof of concept for this approach. The carboxyl groups in the tetracarboxy cobalt phthalocyanine were conjugated with phthalocyanine macrocycles which could extend the π-electron conjugation system of HOF-CoPcTc. Remarkably, the decomposition rate of the sulfamethoxazole (SMX) molecule in an aqueous solution was about 99% after 120 min under visible light irradiation for HOF-CoPcTc, which is a significant 9.78-fold improvement over that of the ligand CoPcTc. This study demonstrated that metal phthalocyanine compositions with carboxyl groups can be used to successfully synthesize HOF materials for large conjugated systems and provide a useful method for achieving efficient photocatalytic degradation of antibiotics. [ABSTRACT FROM AUTHOR]

Carbonization of waste material into functional carbonaceous material is a benign way of utilizing biomass. Herein, we report the decoration of SnS2 nanoparticles on the biochar carbonaceous material using a facile hydrothermal synthetic strategy. The biomass collected from staminate flowers was pyrolyzed to obtain a biochar material containing a hydrophilic surface that creates an efficient environment for the decoration of SnS2 nanoparticles. The SnS2 decoration was thoroughly investigated using state-of-the-art instrumentation techniques. The morphological investigations indicate the formation of flower-shaped SnS2 nanoparticles with a sufficiently exposed surface for effective surface activities. These include the photodegradation of the methylene blue (MB) dye and electrochemical sensing of Pb2+ and Hg2+ ions. The SnS2@BC composite exhibits superior photocatalytic activity for the degradation of MB. Almost 95% of MB is removed within 60 min of contact time by a collaborative effect of adsorption and sunlight-driven photocatalysis. The removal of MB followed pseudo-first-order kinetics with a high K1 value of ca. 0.013 min−1. The cyclic voltammetry (CV) and differential pulse voltammetry (DPV) traces of the SnS2@BC modified glassy carbon electrode (GCE) show a decent electrochemical response with limits of detection of ca. 0.28 and 0.55 μM in the case of Pb2+ and Hg2+ respectively. Furthermore, the DFT studies were carried out on a simulated model material and the results were in line with the experimental data. This work provides an economical treatment method for the photodegradation and electrochemical sensing of toxic contaminants present in wastewater. [ABSTRACT FROM AUTHOR]

In this paper, three-dimensional TiO2 nanoflowers (NFs) were prepared by a facile hydrothermal method, and Ag3PO4 was grown in situ following alkali treatment to design and synthesize a Ag3PO4/OH/TiO2 catalyst with excellent photocatalytic activity under visible light. The test results show that the photocatalytic degradation performance of TiO2 NFs after alkali treatment and Ag3PO4 loading is significantly improved. This is because the alkali treatment and the introduction of Ag3PO4 can provide a large amount of –OH, which can be converted to ˙OH under UV irradiation, followed by an increase in the number of active radicals to enhance the photocatalytic degradation performance. Meanwhile, the introduction of Ag3PO4 can effectively improve the light absorption ability of the photocatalyst. Moreover, the in situ growth of Ag3PO4 on TiO2 NFs can construct a high-quality Ag3PO4/TiO2 heterojunction to promote the charge separation and transport. Therefore, the degradation rate of Ag3PO4/OH/TiO2 can reach 90% after 30 min for degrading 3 mg L−1 RhB under visible light. The Ag3PO4/OH/TiO2 photocatalyst designed in the present work provides a new tool for the degradation of organic dyes. [ABSTRACT FROM AUTHOR]

Tuning of vacancies in photocatalytic materials has emerged as a versatile strategy to enhance visible light absorption and photocatalytic activity. In this study, surface oxygen vacancies (defects) were incorporated on antimony tungstate to boost its photocatalytic activity, which was examined by studying the degradation of model pollutants under visible light irradiation. Specifically, a two-to-three-fold increase in photocatalytic activity was observed for oxygen vacancy-rich antimony tungstate in comparison to its pristine counterpart. This improvement in the photocatalytic performance can be attributed to the presence of oxygen vacancies in the material, which leads to an enhanced absorption of light, decrease in the recombination of charge carriers, and increase in the number of active sites. In addition, owing to the nature of the surface charge present, the photocatalysts were found to be selective for the degradation of cationic pollutants in comparison to anionic and neutral pollutants, and can thus be used for the separation of a mixture of pollutants. Furthermore, scavenger studies illustrate that holes play a major role in the photocatalytic degradation of pollutants. Moreover, the excellent photostability of oxygen vacancy-rich antimony tungstate over three consecutive cycles demonstrates its potential as a good photocatalyst for the degradation of pollutants. Overall, this study demonstrates that the engineering of surface vacancies on perovskite oxide materials can render them as efficient single component photocatalysts for environmental remediation applications. [ABSTRACT FROM AUTHOR]

Perovskite materials are emerging as the most promising and efficient low-cost energy materials for various applications. The construction of heterojunctions has become a field of interest because of their high potential to give off a large amount of energy. Herein, a Z-scheme heterojunction was made between two perovskites (CoTiO3 and CaTiO3) in order to make a cheap material that is good at photocatalysis. Various methods were used to characterize the resulting CoTiO3/CaTiO3 (CCO 75: 25) composite, including XRD, Raman, XPS, HRSEM, HRTEM, BET, and UV-vis. The increased photocatalytic activity of the CoTiO3/CaTiO3 (CCO) composite is attributed to the accelerated charge transfer from O2- to Ti4+ and from Co2+ to Ti4+ ions, revealing the close interfacial contact between CoTiO3 and CaTiO3, and spatial charge transfer within the CoTiO3/CaTiO3 heterojunction. A direct Z-scheme mechanism was developed, and charge transfer properties were verified by the scavenger test and ESR, PL, and EIS analyses. The enhanced degradation rate of k = 0.0373 min-1 is achieved for the CCO 75: 25 composite. Meanwhile, the CCO 75: 25 composite established high photocatalytic stability when recycled for CBZ degradation. This research offers mechanistic and practical views on designing simple and cost-effective materials for pollutant removal. [ABSTRACT FROM AUTHOR]

In this experiment, a novel heterostructured nano-TiO2/LaMnO3 composite photocatalyst was prepared by the sol–gel method, and the crystalline shape, morphology and photoresponse of the samples were analysed by combining XRD, FI-IR, SEM, TEM, BET, XPS, UV-Vis and PL characterization techniques, and the effects of different composite ratios, catalyst dosage, ammonia–nitrogen aqueous concentration and pH on the photocatalysis of the photocatalytic degradation of ammonia–nitrogen were investigated by combining with kinetic simulations. The results showed that T/LMO has a polyhedral shape with a microporous structure, a particle size of about 30 μm, and a band gap of 2.82 eV. After irradiation with a 25 W, 254 nm UV lamp for 3 h, T/LMO (1 : 2) could exhibit a 61.15% degradation rate in 100 mL NH4Cl solution with a mass concentration of 75 mg L−1 and pH 5, the degradation rate was still 52.5% after three times of recycling, the degradation products were mainly non-toxic nitrate nitrogen and nitrogen gas, and it was also experimentally demonstrated that ˙O2− and ˙OH are active radicals that play an important role in the photocatalytic degradation process. Finally, the experimental results were verified in conjunction with the results of photoelectrochemical tests, demonstrating that the binary composite T/LMO is a Z-type heterojunction structure. With good performance of photocatalytic degradation of ammonia nitrogen, reduced electron–hole pair complexation, and an increased photogenerated carrier migration rate, this study provides some theoretical knowledge and experimental evidence for the practical application of novel photocatalysts in the removal of ammonia nitrogen from wastewater. [ABSTRACT FROM AUTHOR]

Based on the anion exchange strategy, a novel Bi2S3/BiOCl0.1Br0.9 S-scheme heterojunction was prepared via a facile one-step low-temperature water bath method for the first time. In this process, 2D Bi2S3 nanosheets were controllably grown on the surface of a 3D hollow BiOCl0.1Br0.9 solid solution. Under visible light irradiation, the as-prepared 3BS-BCB exhibited a remarkable photocatalytic degradation efficiency of 99.67% toward rhodamine B (Rh B) within 140 min, which is approximately 3.57 times higher than that of the BiOCl0.1Br0.9 solid solution alone. The enhanced photocatalytic performance is attributed to the formation of an interfacial electric field (IEF), which accelerated the separation rate of photoinduced electron–hole pairs and coupled the strong redox ability of both the semiconductors. Moreover, the photosensitive effect of Bi2S3 extended its light absorption range, increasing the yield of photogenerated charge carriers. Such thermodynamic and kinetic compatibility is the fundamental reason for the enhanced photocatalytic efficiency. This study provides new insights into the design of S-scheme heterojunction photocatalysts with visible light response and high redox ability based on wide-band gap semiconductors. [ABSTRACT FROM AUTHOR]

Designing efficient catalysts with strong redox characteristics and high visible light absorption is of particular interest in the field of photocatalysis. In this study, we synthesized an active and cost-effective photocatalyst by combining MOF-derived La/Fe bimetallic LaFeO3 porous nanosheets with hydrothermally synthesized CdS nanorods. Several p-LaFeO3/n-CdS photocatalysts with different concentrations (wt%) of LaFeO3 were synthesized, and their physicochemical properties were characterized by standard analytical techniques such as UV-vis DRS, FTIR, XRD, BET, SEM, TEM, EDX and XPS. The photocatalytic degradation performance of the synthesized materials was evaluated using chromophoric dyes such as rhodamine B (RhB) and congo red (CR) and antibiotics such as tetracycline (TC) and oxytetracycline (OTC) under visible light irradiation in aqueous suspension. The as-synthesized 15 wt% p-LaFeO3/n-CdS (15 LC) heterojunction photocatalyst exhibited remarkable photocatalytic degradation performance against RhB (96%, 30 min), CR (98%, 25 min), TC (80%, 100 min), and OTC (78.6%, 75 min). The reactive oxygen species such as O2˙−, h+, and ˙OH were involved in the degradation process, which was monitored through scavenger tests. The heterojunction photocatalyst effectively suppressed photoinduced electron–hole pair recombination and facilitated interfacial charge transfer. Based on experimental data and projected energy band positions, a type II mechanism is proposed to elucidate the photocatalytic degradation of organic contaminants, emphasizing the redox capabilities and broad visible light absorption of the synthesized photocatalyst. The phototransformation of 4-nitrophenol to 4-aminophenol and adsorption isotherms were also done using the 15 LC heterojunction photocatalyst, whereas in the case of the adsorption isotherms the curve fitted the Langmuir isotherm model. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) emerge as innovative photocatalysts featuring systematically tuned chemical structures, nano-porosity, and photoelectric properties. We have shown in the last years that COFs are excellent photocatalysts and they are able to produce hydrogen peroxide (H2O2) from oxygen and water. Despite the recent surge in the photosynthesis of H2O2 using COFs, its subsequent application for tandem pollutant remediation as a tangible green alternative to Fenton chemistry has not yet been comprehensively explored. In this study, we synthesized three highly crystalline sp2 COFs with different donor–acceptor (D–A) strengths, employing triazine units as the electron acceptor moiety. The D–A alignment promotes photogenerated charge separation, augmenting the photocatalytic process, which resulted in the TMT-TT-COF achieving a H2O2 production rate of 1952 μmol g−1 h−1 without any sacrificial agents. The COFs also manifested a rapid photocatalytic degradation of bisphenol A (BPA) from a variety of real-life waterbodies. This study pioneers the in situ H2O2 production via COFs to subsequently generate other reactive oxygen species (ROS) for direct organic pollutant degradation in the visible region. [ABSTRACT FROM AUTHOR]

Coordination polymers are a sub-class of coordination complexes that possess unique opto-electronic properties and hence can be utilized for a wide range of applications such as sensing and photocatalysis. Herein, four new coordination polymers (CPs) with formula [Mn2(HL)(NMP)(H2O)2]n (1), [Mn2(HL)(DMA)2(H2O)·2DMA]n (2), [Mn(H3L)(H2O)2]n (3) and [Mn(H3L)(H2O)(4,4′-bipy)]n (4) (H5L = 3,5-bis(3,4-dicarboxyphenoxy) benzoic acid and NMP = N-methyl pyrrolidone) were synthesized under hydrothermal conditions and characterized. The single-crystal X-ray analysis revealed a distorted octahedral geometry around Mn(II) in these CPs and that they form an extended hydrogen bonding and π⋯π stacking interaction-assisted network. Thermogravimetric studies revealed that the CPs, 1, 2, 3 and 4, have variable thermal stability in the range of 82–194 °C. All four complexes exhibited optical semiconducting behavior and hence were used as photocatalysts for the photodecomposition of antibiotics, including chloramphenicol (CAP), nitrofurazone (NFZ), ornidazole (ODZ), oxytetracycline (OXY) and sulfamethoxazole (SMT). Among the CPs, CP 2 exhibited an impressive 91.93% degradation of NFZ within 60 min. The plausible photocatalytic mechanism was explained with the assistance of Hirshfeld surface analysis. [ABSTRACT FROM AUTHOR]

A nanocomposite (TiO2/NiFe2O4@MWCNTs) was synthesized through hydrothermal methods, combining NiFe2O4, TiO2, and MWCNTs. The material underwent characterization using various analytical methods, including XRD analysis, SEM, TEM, EDS, UV-vis spectroscopy, PL analysis, FT-IR, Raman spectroscopy, and BET analysis. The average size of a nanoparticle is 36 nm, as determined by transmission electron microscopy and the Scherrer formula. UV-visible examination reveals that the TiO2/NiFe2O4@MWCNTs nanocomposite has an energy band gap of 1.5 eV. The resultant nanocomposite has a specific surface area of 70.5 m2 g−1 and a pore volume of 0.29 cc g−1. These analyses demonstrated that the inclusion of MWCNTs effectively inhibited charge carrier recombination in both NiFe2O4 and TiO2 nanoparticles. The catalyst's efficiency was evaluated in a batch reactor under diverse conditions, including different nanocomposite dosages, CIP concentrations, and pH levels. The degradation of CIP was explored through photocatalytic experiments with varying nanocomposite dosages, revealing that a dosage of 0.5 g L−1 resulted in an 83.5% degradation efficiency (CIP: 40 mg L−1, pH = 6, 120 min, 120 W m−2). Different CIP concentrations were also tested, showing that a concentration of 10 mg L−1 achieved a degradation performance of 93.5% (catalyst: 0.5 g L−1, pH = 6, 120 min, 120 W m−2) and an efficiency of 97.2% at a pH of 10. The optimal conditions for CIP degradation were determined as 0.5 g L−1 of nanocatalyst, a CIP concentration of 10 mg L−1, and a pH of 10. These optimal parameters were then applied to assess CIP degradation using NiFe2O4 and NiFe2O4/MWCNTs as individual materials. Trapping analyses have established that H+ and OH˙, which are reactive radicals, are the main agents responsible for the breakdown of CIP. The highest agreement with the experimental data was obtained by applying a pseudo-first-order kinetic model, which had an R2 value of 0.97 for a range of CIP concentrations. Notably, even after four consecutive uses, the photocatalysts maintained their original efficiency, experiencing a minimal decrease of less than 3.2% in CIP degradation. Due to its straightforward synthesis, excellent stability, and potential for recycling, TiO2/NiFe2O4@MWCNTs demonstrated promising performance in degrading CIP antibiotics, suggesting its suitability for removing and breaking down pharmaceutical organic contaminants in water systems. [ABSTRACT FROM AUTHOR]

Photodegradation of aqueous organic pollutants provides an ideal removal process for wastewater treatment, urging the development of photocatalysts with high-performance, inexpensiveness and good reusability. Herein, we report the integration of a boron-dipyrromethene (BODIPY) unit and a β-cyclodextrin (β-CD) unit into a polymer network to generate a hyper cross-linked polymer (CDP). As anticipated, this particular CDP polymer combines the advantageous features of an adsorbent and a photosensitizer, thereby showcasing meticulously balanced adsorption and photodegradation processes. This unique synergy culminates in the effective deterioration of bisphenol A (BPA) in aqueous solutions through photocatalytic reactions. Significantly, the utilization of the CDP polymer in photodegradation processes exhibits remarkable ability to withstand environmental variations, encompassing pH levels, coexisting ions, and water matrices. Moreover, it demonstrates excellent recyclability, further enhancing its appeal as a sustainable solution. This work provides a new platform for designing and preparing high-performance and economical POP-based photocatalysts for efficient wastewater treatment. [ABSTRACT FROM AUTHOR]

The pyrolysis of metal–organic frameworks (MOFs) has emerged as a promising route to synthesize carbon/metal oxide-based materials with diverse phase compositions, morphologies, sizes and surface areas. In this paper, 1,3,5-benzoic acid (BTC) and 2,4,6-tri(4-pyridinyl)-1-pyridine (TPP) were used as ligands to prepare a novel cobalt-based MOF (Co-MOF) which was used as a precursor to obtain five carbon-based materials at different temperatures (Co-C200/400/600/800/1000). Furthermore, five dyes were used as degradation targets to investigate the photocatalytic degradation performance of the title materials under UV light irradiation. Co-C1000 exhibited the best photocatalytic degradation performance for methyl orange (MO), and the degradation rate could reach 99.21%. The enhanced photocatalytic activity was attributed to narrower band-gaps and a synergistic effect originating from the well-aligned straddling band structures between Co/CoO/Co3O4 and C, also resulting in a faster interfacial charge transfer during the photocatalytic reaction. This study will aid in the development of photocatalysts generated from carbon-based materials via the pyrolysis transformation of MOFs, therefore greatly enhancing the photocatalytic performance. [ABSTRACT FROM AUTHOR]

The photodegradation of propranolol (PRO) by BiOCl0.5I0.5/persulfate under visible light was comprehensively investigated. The results demonstrated a significant increase in the removal efficiency of PRO under visible light irradiation, achieved by the combination of BiOCl0.5I0.5 solid solution and persulfate (PS). The photocatalytic activity of the system was found to be enhanced with an increase in the pH value. Additionally, the addition of a certain amount of PS improved the degradation of PRO. The presence of typical water constituents, Cl− and NO3−, had a negligible impact on PRO removal. In contrast, the increasing concentration of humic acid (HA) exhibited apparent inhibition of PRO degradation. Furthermore, radical scavenging experiments revealed that the removal of PRO was primarily facilitated by active free species, including h+ and ˙O2−. The presence of characteristic peaks of ˙OH (peak ratio 1 : 2 : 2 : 1), 1O2 and ˙SO4− in the EPR spectrum indicates that these three radicals are also involved in the degradation process. Moreover, the BiOCl0.5I0.5/PS system demonstrated excellent photocatalytic activity, as well as favorable reusability and stability. This study offers new insights into the photocatalytic degradation of PRO, presenting a promising approach in this field. [ABSTRACT FROM AUTHOR]

Transition-metal coordination complexes have attracted wide attention in molecular chemistry, but their applications still confront a tremendous challenge. Herein, a novel silver coordination polymer with a formula of {[Ag9(TIPA)6](NO3)9·12H2O}n (Ag-TIPA) was prepared by a solvothermal reaction of silver nitrate with triangular tris(4-imidazolylphenyl)amine (TIPA). The crystalline molecular structure was determined by single-crystal X-ray diffraction, which showed that each Ag(I) was coordinated with two nitrogen atoms of TIPA ligands. Such Ag-TIPA was used as a catalyst for the photodegradation of ciprofloxacin and 4-nitrophenol under UV-visible light irradiation. The results exhibited excellent photocatalytic performance and reusability due to high structure stability in an acidic, neutral and alkaline environment. The experimental findings and density functional theory calculations revealed that metal–ligand charge transfer in Ag-TIPA extended the absorption range of light and improved the charge transfer properties of TIPA. To further understand the photodegradation process, the intermediates were predicted and analysed through electrostatic potential, orbital weighted dual descriptor, and liquid chromatography-mass spectrometry techniques. Based on these findings, a possible degradation mechanism was proposed. This study provides new insights into the design and synthesis of Ag-based coordination polymers with novel structures, excellent catalytic activity, and good durability. [ABSTRACT FROM AUTHOR]

A robust and porous titanium metal–organic framework (Ti-MOF; LCU-505) has been solvothermally synthesized based on an unprecedented tetranuclear Ti2(μ3-O)2Tb2(μ2-CH3COO)2(H2O)4(OOC−)8 cluster (abbreviated as [Ti2Tb2]) and tritopic 4,4′,4′′-s-triazine-2,4,6-triyl-tribenzoic acid ligand (H3TATB). LCU-505 shows remarkable water stability and permanent porosity for N2 and CO2 gas adsorption. Moreover, LCU-505 demonstrates n-type semiconductor behavior and good photocatalytic activity in the degradation of organic dyes. [ABSTRACT FROM AUTHOR]

Tetrabromobisphenol A (TBBPA), a prevalent brominated flame retardant, poses significant environmental and health risks, necessitating its removal. In this study, WO3 with different structures was synthesized for TBBPA photodegradation under visible light using H2O2 and O2 as oxidants. The catalyst exhibited robust stability and reusability, rendering it suitable for practical applications. The crystalline structure and surface structure of WO3 controlled its catalytic activity towards TBBPA photodegradation. Monoclinic WO3 with the (022) plane was found to be the most active for ˙O2− active species generation from H2O2 and thus active for TBBPA degradation. Degradation product analysis showed that the catalyst was active not only for the removal of TBBPA, but also for the debromination of TBBPA. Nearly 100% debromination was achieved. [ABSTRACT FROM AUTHOR]

NiFe-LDH/g-C3N4 (LDH/CN) heterostructures with different amounts of NiFe-LDH (LDH) were prepared by a hydrothermal method and characterized using different experimental techniques. Their photocatalytic properties were investigated using the degradation of tetracycline hydrochloride (TC) and the production of hydrogen from water splitting. Experimental results showed that the hydrogen production rate (780.5 μmol g−1 h−1) was 2.29 times that of pristine CN, and the TC removal rate (76.3%) of 1.8LDH/CN was 3.71 times that of CN. According to the detailed study of the structural, optical, and photoelectrochemical properties, a type II charge transfer mechanism was proposed to explain the improved photocatalytic performance of LDH/CN. [ABSTRACT FROM AUTHOR]

Herein, hollow hZrO2/g-C3N4 composite photocatalysts were successfully fabricated using polymethylacrylic acid (PMAA) nanospheres as sacrificial templates via reflux-precipitation polymerization and subsequent ZrO2 layer coating by sol–gel method over PMAA nanospheres, calcining process, and forming composites with g-C3N4 in sequence. The formation mechanism of the unique composites was proved by FESEM, TEM, XPS, XRD, and EDX mapping characterizations. The photodegradation tests of methylene blue (MB) and ciprofloxacin (CIP) were used to investigate the photocatalytic activity. The results revealed that hZrO2/g-C3N4 exhibited significantly boosted photocatalytic activity for degrading 99.7% methylene blue and 81.5% ciprofloxacin in 120 min under simulated sunlight irradiation (Xe lamp, 500 W), which was much better than that of hZrO2 (42.1% for MB and 19.1% for CIP). The enhanced performance is presumably attributed to the synergetic interaction of the two components and the efficient separation of the photoproduced electron–hole pairs between ZrO2 and g-C3N4, which was verified using photocurrent and EIS characterizations. On the basis of the scavenging studies of free radicals (e−, h+, ˙O2−, and ˙OH), the mechanism of the boosted photocatalytic activity was proposed. More significantly, the composites presented excellent reusability confirmed by cyclic photocatalytic degradation experiments, which is crucial for the sustainable and green applications of photocatalysts. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks and coordination polymers (MOFs/CPs) have emerged as a rare category of multidimensional materials with applications in many fields, particularly as photocatalysts for aromatic dyes and for the luminescent sensing of volatile organic solvents (VOCs), anions, cations, etc. Herein, a luminescent zinc(II) coordination polymer (ZnCP) was prepared using 3,5-diamino triazole (DAT) and 1,3,5-benzenetricarboxylic acid (BTC) under solvothermal conditions and was fully characterized by FTIR spectroscopy, powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) analysis, and single X-ray crystallography. Moreover, the photocatalytic performance of the ZnCP in decomposing an aqueous solution of methyl green (MG) was examined. Photocatalysis results indicated a 99.61% efficiency in the presence of the ZnCP under visible light. Furthermore, an active species trapping experiment helped deduce a possible photocatalysis mechanism of MG degradation. Interestingly, the ZnCP also acted as a potential luminescent sensor for the detection of cations Fe3+ and Cu2 and anions Cr2O72− and MnO4−, with outstanding limit of detection (LOD) values of 2.44 nM for Fe3+, 3.50 nM for Cu2+, 3.14 nM for Cr2O72−, and 2.54 nM for MnO4−. Thus, the designed luminescent zinc(II) coordination polymer holds the potential to act as a photocatalyst as well as a luminescent sensor. [ABSTRACT FROM AUTHOR]

In this work, N-graphyne is in situ coupled with BiOCl0.5Br0.5via a facile one-step sonochemical method. To our knowledge, both the synthesis strategy for BiOCl0.5Br0.5 and the N-graphyne/BiOCl0.5Br0.5 photocatalytic system are new developments. A collection of characterization methods is adopted to detect the morphologies, structures, and electronic and optical properties. The results demonstrate that wrinkle-like N-graphyne nanosheets successfully enwind around or on flower-like BiOCl0.5Br0.5 microspheres, which are regularly assembled by BiOCl0.5Br0.5 nanosheets. Compared with pristine BiOCl0.5Br0.5, N-graphyne/BiOCl0.5Br0.5 composites exhibit superior adsorption capacity and visible-light-driven photocatalytic degradation of levofloxacin. In particular, the optimal N-graphyne amount for ameliorating the photocatalytic performance of BiOCl0.5Br0.5 is ascertained. In addition, the good stable performance for photocatalysis is confirmed by four cycling experiments. The dominant active species is confirmed to be O2˙− during photodegradation. The improved photocatalytic activity is attributed to the enhanced visible light response and the accelerated transfer/separation of photogenerated carriers by N-graphyne, which are verified using UV–vis absorption spectra, photocurrents, photopotentials, Nyquist plots, and Mott–Schottky curves. This study develops a new perspective for the synthesis and modification of BiOX solid solution, which can be used as an efficient photocatalyst. [ABSTRACT FROM AUTHOR]

The photocatalytic degradation of organic dyes has become the focus of a considerable number of research groups. In this work, a green synthesis route towards the fabrication of a Zn0.98Mn0.02O/BiOCl nanocomposite using lemon peel extract is presented. The synthesized samples were characterized by powder X-ray diffraction, Fourier transform infrared, transmission electron microscopy, XPS analysis and UV-visible spectrophotometry analysis. The photocatalytic activities of the synthesized nanoparticles and nanocomposite were studied by monitoring the degradation of methylene blue and methyl orange dyes under visible light. The photocatalytic degradation of the dyes using the synthesized materials was confirmed by the color of the residual sample and UV-visible spectrophotometry. The synthesized nanocomposite showed an enhanced efficiency towards photocatalytic degradation and under optimal conditions, the maximum removal of up to 96% of methylene blue and 94% of methyl orange can be achieved in just 60 minutes. The generation of superoxide and hydroxyl radicals through the heterojunction between Zn0.98Mn0.02O and BiOCl was the reason for the enhanced degradation efficiency as confirmed by radical scavenger tests. [ABSTRACT FROM AUTHOR]

AgI/BiOI composites were prepared with BiOI nanosheets as the substrate by in situ ion exchange and characterized by a series of characterization methods. The photocatalytic performance tests showed that the effective separation of photogenerated electron–hole pairs and the photocatalytic activities of the AgI/BiOI composites could be achieved by adjusting the Ag/Bi molar ratios, which may result in changes in the composition and structure of the AgI/BiOI composites. Among them, the AgI/BiOI-1.2 sample with a Ag/Bi molar ratio of 1.2 demonstrated a Bi5O7I composition and the highest separation efficiency of photogenerated electron–hole pairs, as well as the best photocatalytic performance for norfloxacin (NOR) photodegradation. More than 98.8% of NOR could be removed over AgI/BiOI-1.2 within 120 min under the optimum conditions. Radical quenching experiments confirmed that the photogenerated holes and ˙O2− radicals played significant roles during the process of photocatalytic NOR degradation. A possible Z-type heterojunction mechanism for the photocatalytic degradation of NOR over AgI/BiOI-1.2 was proposed. [ABSTRACT FROM AUTHOR]