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Mixed-dimensional van der Waals heterojunctions (MD-vdWhs), known for exceptional electron transfer and charge separation capabilities, remain underexplored in photocatalysis. In this study, we leveraged the synergistic effect of intermolecular π â π* and D-π-A dual channels to fabricate novel MD-vdWhs. Owing to the synergistic effect, it exhibits superior electron transfer and delocalization ability, thereby enhancing its photocatalytic performance. The Optimal photocatalyst can degrade 98.78 % of 20 mg/L tetracycline (TC) within 15 min. Additionally, we introduced a novel proof strategy for investigating the photoelectron transfer path, creatively demonstrating the synergistic dual channels effect, which can be attributed to the carbonyl density and light-excitation degree. Notably, even under low-power light sources, it achieved complete inactivation of Escherichia coli within just 7 mins, far surpassing current cutting-edge research. This theoretical framework holds promise for broader applications within related studies.
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Sterile inflammation, characterized by a persistent chronic inflammatory state, significantly contributes to the progression of various diseases such as autoimmune, metabolic, neurodegenerative, and cardiovascular disorders. Recent evidence has increasingly highlighted the intricate connection between inflammatory responses and cardiovascular diseases, underscoring the pivotal role of the Stimulator of Interferon Genes (STING). STING is crucial for the secretion of type I interferon (IFN) and proinflammatory cytokines in response to cytosolic nucleic acids, playing a vital role in the innate immune system. Specifically, research has underscored the STING pathway involvement in unregulated inflammations, where its aberrant activation leads to a surge in inflammatory events, enhanced IFN I responses, and cell death. The primary pathway triggering STING activation is the cyclic GMP-AMP synthase (cGAS) pathway. This review delves into recent findings on STING and the cGAS-STING pathways, focusing on their regulatory mechanisms and impact on cardiovascular diseases. It also discusses the latest advancements in identifying antagonists targeting cGAS and STING, and concludes by assessing the potential of cGAS or STING inhibitors as treatments for cardiovascular diseases.
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Enfermedades Cardiovasculares , Proteínas de la Membrana , Nucleotidiltransferasas , Transducción de Señal , Humanos , Nucleotidiltransferasas/metabolismo , Enfermedades Cardiovasculares/metabolismo , Enfermedades Cardiovasculares/inmunología , Proteínas de la Membrana/metabolismo , Animales , Inmunidad Innata , Inflamación/inmunología , Inflamación/metabolismoRESUMEN
Notable differences in photo-physical and chemical properties were found between bulk water and solid phase extraction (SPE) isolates for dissolved organic matter (DOM). The moieties extracted using modified styrene divinylbenzene cartridges, which predominantly consist of conjugated aromatic molecules like humic acids, contribute mainly to light absorption but exhibit lower quantum yields of fluorescence and photo-produced reactive intermediates (PPRIs). Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) revealed lignin as the moieties displaying most significant variance in abundance. In Van Krevelen-Spearman plot, we observed molecules positively or negatively correlated with DOM's optical and photochemical properties (including SUVA254, steady-state concentrations of ·OH, 1O2 quantum yield, etc.) were confined to specific regions, which can be delineated using a threshold modified aromaticity index (AImod) of 0.3. Based on the relationships between optical properties and PPRI production, it is suggested that the energy gap between ground state and excited singlet state (â³ES1âS0), governing the inner conversion rate, serves as a determinant for apparent quantum yield of PPRIs in DOM, with intra-molecular charge transfer (CT) interactions potentially playing a pivotal role. Regarding DOM's photoreactivity with pollutants, this study has revealed, for the first time, that protein/amino sugars/amino acids could act as antioxidant groups in addition to phenols on the photolysis of sulfadiazine. These findings provide valuable insights into DOM photochemistry and are expected to stimulate further research in this area.
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Extracción en Fase Sólida , Sustancias Húmicas , Compuestos Orgánicos/químicaRESUMEN
In response to antibiotic residues in the water, a novel advanced oxidation technology based on MgO2 was used to remediate sulfamethazine (SMTZ) pollution in aquatic environments. Upon appropriate regulation, the remarkable removal efficiency of SMTZ was observed in a UV/MgO2 system, and the pseudo-first-order reaction constant reached 0.4074 min-1. In addition, the better performance of the UV/MgO2 system in a weak acid environment was discovered. During the removal of SMTZ, the pathways of SMTZ degradation were deduced, including nitration, ring opening, and group loss. In the mineralization exploration, the further removal of residual products of SMTZ by the UV/MgO2 system was visually demonstrated. The qualitative and quantitative researches as well as the roles of reactive species were valuated, which revealed the important role of ·O2-. Common co-existing substances in actual wastewater such as NO3- HA, Cl-, Fe2+, Co2+, and Mn2+ can slightly inhibit the degradation of SMTZ in the UV/MgO2 system. Finally, the capacity of efficient degradation of SMTZ in actual wastewater by the UV/MgO2 system was proved. The results indicated that the innovative UV/MgO2 system was of great practical application prospect in antibiotic residue wastewater remediation.
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Contaminantes Químicos del Agua , Purificación del Agua , Antibacterianos/química , Óxido de Magnesio , Aguas Residuales , Peróxido de Hidrógeno/química , Contaminantes Químicos del Agua/química , Rayos Ultravioleta , Sulfametazina/química , Sulfanilamida , Oxidación-Reducción , Cinética , Sulfonamidas , Purificación del Agua/métodosRESUMEN
To predict PPCPs' photolysis rate in natural aquatic environment, it is essential to grasp the reaction rates between DOM and PPCPs, yet there are few measured data and no prediction models for this important photochemical parameter. To address this, a reaction rate coefficient (αDOM) was defined to describe the apparent rate of DOM-involved photoreaction for PPCPs. The measured αDOM values for 40 PPCPs in 9 DOM samples varied dramatically, ranging from (-2.1 ± 0.1)× 1010 to (2.2 ± 0.1)× 1011 M-1 s-1. Then the quantitative structure-activity relationship (QSAR) models were developed using chemical and water quality descriptors via the random forest method. We initially separated positive and negative values by a classifier with an AUC value of 0.965, followed by the construction of regression models for positive and negative values, respectively, using a regressor. Positive models achieved satisfactory goodness-of-fit and predictive ability (R2adj=0.92 and Q2ext=0.86), while negative models demonstrated acceptable performance (R2adj=0.71 and Q2ext=0.70). Finally, a comprehensive photolysis model that incorporates the QSAR models for αDOM was established and the significance of water quality parameters was emphasized through sensitive analysis. This model enables more elaborate predictions of PPCPs' photolysis rates in various water samples, providing valuable assistance for forecasting PPCPs' environmental fate.
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The attenuation characteristics of PPCPs play an important part in predicting their environmental concentrations. However, considerable uncertainty remains in reported laboratory data on the attenuation characteristics of PPCPs. In this analysis, we compile information on laboratory-observed photodegradation half-lives (t1/2), biodegradation t1/2, the organic carbon normalized adsorption constant (KOC) and field-observed overall attenuation t1/2 for PPCPs in water bodies from more than 200 peer-reviewed studies. To mitigate the effects of such uncertainty, we derive representative values (RV) for PPCP degradability from these records to better compare the characteristics of different PPCPs. We further examine the influence of experimental conditions and environmental drivers on the determination of t1/2 using difference analysis and correlation analysis. The results indicate that for laboratory photodegradation tests, different light sources, initial concentration and volume significantly affect t1/2, whereas there is no significant difference between values obtained from tests conducted in pure water and natural water. For biodegradation, laboratory-measured t1/2 values in batch, flume and column studies gradually decrease, marking the controlling role of experimental setup. Redox condition, initial concentration and volume are also recognized as important influencing factors. For adsorption, water-sediment ratio is the primary reaction parameter. As two frequently investigated factors, however, pH and temperature are not significant factors in almost all cases. In field observations, the persistence of carbamazepine, typically used as a tracer, is in doubt. Water depth and latitude are the most correlated drivers of t1/2, indicating the predominant status of photodegradation in the overall attenuation rates. These findings call for caution when selecting experimental parameters and environmental drivers in determining PPCP's attenuation rates and establishing PPCP fate models in the field.
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To determine and predict the reaction rate between 3DOM* and PPCPs in various water bodies, this study defines a reaction rate coefficient ( [Formula: see text] ) to describe the reaction between 3DOM* and PPCPs. As the values also included the inhibition effect of DOM's antioxidant moieties, the calculation of [Formula: see text] is inconsistent with that of a bimolecular rate constant via the steady-state kinetic method. The [Formula: see text] values of 12 selected PPCPs were determined in two DOM solutions and ten DOM-containing water samples collected from typical surface water bodies in Beijing. The Pearson coefficients between nine predictors including the absorbance ratio (E2/E3), specific absorption coefficient at 254 nm (SUVA254), fluorescence index (FI), biological index (BIX), humification index (HIX), pH, total organic carbon (TOC), total fluorescence intensity (TFI) and TOC normalized TFI (TFI/TOC) and [Formula: see text] were examined. Correlation patterns for sulfonamides, ß-blockers and diclofenac supported the electron transfer pathway, and was distinctly different from those appeared for FQs where quenching effect played a main part. TFI and TFI/TOC were recognized as the most useful surrogates in empirically predicting [Formula: see text] . For PPCPs that went through the electron transfer pathway, [Formula: see text] could be well fit to the Rehm-Weller model assuming a proportional relationship between TFI and â³Get. For FQs, [Formula: see text] was found to linearly correlated with TFI/TOC. The [Formula: see text] values determined in this study enrich the database of PPCPs photolysis parameters, and the correlation analysis provides reference for forecasting PPCPs fate in the aquatic environment.
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Effective photoexcitation and carrier migration are the essential aspects to strengthen semiconductor-engaged redox reaction. Herein, a three-dimensional thin-wall hollow porous cystic-like g-C3N4 (HPCN) with curved layer edge was successfully fabricated via a non-template thermal-condensation strategy. The construction of unique distorted structure can evoke the hard-to-activate nâπ* electronic transition to some extent, broadening the absorption spectrum to 800 nm. And benefiting from the multiple reflections of incident light, the effective photoactivation can be further achieved. Moreover, the thin-wall porous framework can shorten the diffusion distance and accelerate migration of photogenerated charge, favouring interfacial redox reactions. The optimized HPCN1.0 demonstrated an excellent photocatalytic degradation of SMX under blue-LED light irradiation, which was dramatically superior to that of pristine g-C3N4 (CN, 11.4 times). Ultimately, in consideration of reactions under several influencing factors with four different water samples, we demonstrated that the HPCN photocatalyst could be utilized far more productively for the elimination of SMX under real-world aqueous conditions. This work provides a straightforward approach for the removal of SMX and has immense potential to contribute to global scale environmental remediation.
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Electrónica , Sulfametoxazol , Porosidad , CatálisisRESUMEN
Highly efficient oxidation, as non-thermal regeneration technology, is a promising method to solve the regeneration problem of spent activated carbon (AC) in wastewater treatment. In this study, FeOCl was confined into activated carbon (FeOCl/AC) for catalytic oxidation of contaminants on AC during the regeneration process. The characterization results of FeOCl/AC showed that amorphous FeOCl was distributed in micropores, mesopores and macropores of AC. The methylene blue (MB)-adsorbed FeOCl/AC had a regeneration efficiency of 93.7 % at neutral pH in the presence of H2O2, much higher than 46.9 % by Fenton oxidation and 33.7 % by H2O2 oxidation. Meanwhile, the spent FeOCl/AC after the adsorption of atrazine, 2,4-dichlorophenol, and ofloxacin had the regeneration efficiencies of 71.5 %, 86.4 %, and 100 %, respectively. Moreover, the regeneration efficiency still reached 87 % in the fifth adsorption-regeneration cycle, and was linearly decreased with the increase of adsorbed amounts of MB. During 6 h regeneration of spent FeOCl/AC, 97 % of adsorbed MB was degraded. Electron paramagnetic resonance and radical trapping experiments indicated that both superoxide and hydroxyl radicals were involved in MB oxidation during the regeneration process.
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Atrazina , Contaminantes Químicos del Agua , Carbón Orgánico/química , Peróxido de Hidrógeno/química , Azul de Metileno/química , Superóxidos , Oxidación-Reducción , Adsorción , OfloxacinoRESUMEN
Stimulator of interferons genes (STING), which is crucial for the secretion of type I interferons and proinflammatory cytokines in response to cytosolic nucleic acids, plays a key role in the innate immune system. Studies have revealed the participation of the STING pathway in unregulated inflammatory processes, traumatic brain injury (TBI), spinal cord injury (SCI), subarachnoid haemorrhage (SAH) and hypoxic-ischaemic encephalopathy (HIE). STING signalling is markedly increased in CNS injury, and STING agonists might facilitate the pathogenesis of CNS injury. However, the effects of STING-regulated signalling activation in CNS injury are not well understood. Aberrant activation of STING increases inflammatory events, type I interferon responses, and cell death. cGAS is the primary pathway that induces STING activation. Herein, we provide a comprehensive review of the latest findings related to STING signalling and the cGAS-STING pathway and highlight the control mechanisms and their functions in CNS injury. Furthermore, we summarize and explore the most recent advances toward obtaining an understanding of the involvement of STING signalling in programmed cell death (autophagy, necroptosis, ferroptosis and pyroptosis) during CNS injury. We also review potential therapeutic agents that are capable of regulating the cGAS-STING signalling pathway, which facilitates our understanding of cGAS-STING signalling functions in CNS injury and the potential value of this signalling pathway as a treatment target.
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Enfermedades del Sistema Nervioso Central , Ferroptosis , Interferón Tipo I , Ácidos Nucleicos , Autofagia/fisiología , Citocinas/metabolismo , Humanos , Inflamación , Interferón Tipo I/metabolismo , Proteínas de la Membrana/metabolismo , Necroptosis , Nucleotidiltransferasas/metabolismo , PiroptosisRESUMEN
This paper aims to provide insights on mechanochemistry as a green and versatile tool to synthesize advanced materials for water remediation. In particular, mechanochemical methodologies for preparation of reagents and catalysts for the removal of organic pollutants are reviewed and discussed, focusing on those materials that, directly or indirectly, induce redox reactions in the contaminants (i.e., photo-, persulfate-, ozone-, and Fenton-catalysts, as well as redox reagents). Methods reported in the literature include surface reactivity enhancement for single-component materials, as well as multi-component material design to obtain synergistic effects in catalytic efficiency and/or reactivity. It was also amply demonstrated that mechanochemical surface activation or the incorporation of catalytic/reactive components boost the generation of reactive species in water by accelerating charge transfer, increasing superficial active sites, and developing pollutant absorption. Finally, indications for potential future developments in this field are debated.
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Contaminantes Ambientales , Agua , Catálisis , Descontaminación , Indicadores y Reactivos , Oxidación-ReducciónRESUMEN
The development of conjugated polymers with intramolecular donor-acceptor (D-A) units has the capacity to enhance the photocatalytic performance of carbon nitride (g-C3N4) for the removal of antibiotics from ambient ecosystems. This strategy addresses the challenge of narrowing the band gap of g-C3N4 while maintaining its high LUMO position. For this study, we introduced the above donor units into g-C3N4 to construct intramolecular D-A structures through the copolymerization of dicyandiamide with creatinine, which strategically extended light absorption into the green region and expedited photoelectron separation. The introduction of electron donor blocks kept the LUMO distributed on the melem, which maintained the high LUMO energy level of the copolymer with the potential to generate oxygen radicals. The as-prepared porous D-A conjugated polymer enhanced the photocatalytic degradation of sulfisoxazole with kinetic constants 5.6 times higher than that of g-C3N4 under blue light and 15.3 times higher under green light. Furthermore, we surveyed the degradation mechanism including the effective active species and degradation pathways. This study offers a new perspective for the synchronous construction of a porous intramolecular D-A conjugated polymer to enhance water treatment and environmental remediation capacities.
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Photocatalytic degradation of typical pharmaceuticals in natural sunlight and in actual water is of great significance. In this study, the oxygen or nitrogen linked heptazine-base polymer (ONLH) was successfully incorporated with TiO2 nanoparticles and formed a TiO2/ONLH nanocomposite which was responded to the natural sunlight. Under natural sunlight, the TiO2/ONLH can effectively degrade ten types of pharmaceuticals. In particular, fluoroquinolone containing N-piperazinyl, and cardiovascular drugs containing long aromatic side chains were easily degraded. The half-life of the best degradation performance of propranolol was less than 5 min. The rate constants of propranolol using the TiO2/ONLH were approximately six- and eight-fold higher than those of pristine TiO2 and ONLH, respectively. Two reactive species (OH and O2-) facilitated the rapid degradation of propranolol, which occurred primarily through the hydroxyl radical addition, ring-opening, and ipso substitution reactions. An acute toxicity test using luminescent bacteria indicated that the toxicity of the propranolol reaction solution gradually decreased with lower total organic carbon (TOC). According to the toxicity evaluation of monomer products, the TiO2/ONLH also reduced the generation of toxic transformation products. The effects of actual water/wastewater have further shown the TiO2/ONLH might be applied for the removal of pharmaceuticals in wastewater.
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Preparaciones Farmacéuticas , Contaminantes Químicos del Agua , Catálisis , Luz Solar , Titanio , Agua , Contaminantes Químicos del Agua/análisisRESUMEN
The extensive use of bisphenol analogues in industry has aggravated the contamination of the water environment, and how to effectively remove them has become a research hotspot. This study presents two imine-based covalent organic frameworks with different pore sizes (COFs) [TAPB (1,3,5-tris(4-aminophenyl)benzene)-Dva (2,5-divinylterephthaldehyde)-PDA (terephthalaldehyde) (COF-1), and TAPB (1,3,5-tris(4-aminophenyl)benzene)-Dva (2,5-divinylterephthaldehyde)-BPDA (biphenyl dialdehyde) (COF-2)], which have achieved the efficient adsorption of bisphenol S (BPS) and bisphenol A (BPA). The maximum adsorption capacity of COF-2 for BPS and BPA obtained from Langmuir isotherms were calculated as 200.00 mg g-1 and 149.25 mg g-1. Both hydrogen bonding and π-π interactions might have been responsible for the adsorption of BPS and BPA on the COFs, where the high adsorption capacity of COFs was due to their unique pore dimensions and structures. Different types of pharmaceutical adsorption studies indicated that COF-2 exhibited a higher adsorption performance for different types of pharmaceuticals than COF-1, and the adsorption capacity was ranked as follows: bisphenol pharmaceuticals > anti-inflammatory pharmaceuticals > sulfa pharmaceuticals. These results confirmed that COFs with larger pore sizes were more conducive to the adsorption of pollutants with smaller molecular dimensions. Moreover, COF-1 and COF-2 possessed excellent pH stability and recyclability, which suggested strong potential applications for these novel adsorbents in the remediation of organic pollutants in natural waterways and aqueous ecosystems.
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Antibiotics are widespread in the environment with notable ecological risk, for which efficient and green removal technologies are demanded. As a kind of g-C3N4-based material with remarkable photocatalytic property, OCN is an oxygen- and nitrogen-linked carbon nitride organic polymer which can be synthesized through a single-step thermal polymerization method. In this study, OCN was applied for the visible-light-driven photocatalytic degradation of a typical fluoroquinolone (FQ) antibiotics enrofloxacin (ENR). The photocatalysis process achieved over 97% ENR removal within 60 min with 0.4 mg/L OCN and 4 mg/L ENR at pH 8.2. The photocatalytic mechanism of OCN at different pH was studied for the first time. It was shown that O2â -, 1O2 and h+ made contributions at neutral or basic pH and 1O2 contributes the most (57.6% at pH 8.2), while â OH played a role only under acidic condition with a contribution rate of 23.8% at pH 3.2. The cleavage of the piperazine ring and the quinolone ring were two main degradation pathways. The common water constituents humic acid and NO3- showed a dual effect, but HCO3- and Cl- inhibited the degradation. The effect of different water matrices was tested under natural sunlight and it was only a tiny disturbance to the degradation rates. The biotoxicity test conducted using Vibrio fischeri indicated that the toxicity of degradation products became negligible after 3 h. This study demonstrated that OCN is a promising candidate for the advanced treatment and in-situ remediation.
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Polímeros , Agua , Catálisis , Enrofloxacina , Compuestos Heterocíclicos con 3 Anillos , Cinética , TriazinasRESUMEN
Hydroxyl radicals (OH) have robust non-selective oxidizing properties to effectively degrade organic pollutants. However, graphitic carbon nitride (g-C3N4) is restricted to directly generate OH due to its intrinsic valence band. In this study, we report a facile environmental-friendly self-modification strategy to synthesize reduced graphitic carbon nitride (RCN), with nitrogen vacancies and CN functional groups. The incorporation of CN enabled to downshift the valence band level, which endowed RCN with the capacity to directly generate OH via h+. Experimental and instrumental analyses revealed the critical roles of nitrogen vacancies and CN groups in the modification of the RCN band structure to improve its visible light absorption and oxidizing capacity. With these superior properties, the RCN was significantly enhanced for the photocatalytic degradation of DCF under visible light irradiation. The self-modification strategy articulated in this study has strong potential for the creation of customized g-C3N4 band structures with enhanced oxidation performance.
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Diclofenaco/química , Grafito/química , Compuestos de Nitrógeno/química , Catálisis , Luz , Oxidación-Reducción , Procesos FotoquímicosRESUMEN
The adsorbents for water treatment and purification are commonly not recyclable because of the lack of a reagent-less "switch" to readily release the adsorbed compounds. Herein, the interface of Bi2O2CO3 (BOC) nanosheets is designed, synthesized, and modified with citric acid, namely, modified Bi2O2CO3 (m-BOC). The m-BOC is able to selectively adsorb methylene blue (MB) in the dark and the adsorbed MB could be released in the light from m-BOC without the addition of any chemicals. The adsorption mechanism is attributed to the electrostatic attraction between positively charged MB and the negatively charged surface of m-BOC. In contrast, the desorption of MB has resulted from the photo-induced charge redistribution on the surface of m-BOC, which unlocks the coordination bond between m-BOC and the carboxylic group. As a result, BOC is recycled. Such a mechanism was verified by both experimental investigation and DFT calculation. This work provides a promising interfacial engineering strategy for the remediation of dye-polluted water and smart separation in chemical engineering.
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Achieving efficient solar utilization is a primary goal in the field of photocatalytic degradation of PPCPs. For this study, a broad-spectrum carbon and oxygen doped, porous g-C3N4 (COCN) was synthesized via a simple co-pyrolysis of dicyandiamide and methylamine hydroiodide (CH5N·HI). The 0.3COCN demonstrated an excellent photocatalytic degradation of indometacin (IDM), which was 5.9 times higher than bulk g-C3N4. The enhanced photocatalytic activity could be ascribed to the broad-spectrum utilization of solar light and improved charge separation efficiency. Reactive species (RSs) scavenging experiments have shown that O2·- and 1O2 were the dominant active species. Further, the 0.3COCN exhibits excellent yield of hydroxyl radicals which was confirmed by electron spin resonance (ESR) spectra. Meanwhile, the degradation pathways of IDM were proposed according the HRAM LC-MS/MS and total organic carbon (TOC). This research provided a new strategy for a broad-spectrum photocatalyst, and a promising strategy for environmental remediation.
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Indometacina/análisis , Luz , Nitrilos/química , Oxígeno/química , Fotólisis , Contaminantes Químicos del Agua/análisis , Catálisis , Transporte de Electrón/efectos de la radiación , Peróxido de Hidrógeno/química , Nitrilos/efectos de la radiación , Oxidación-Reducción , Porosidad , Propiedades de SuperficieRESUMEN
Pharmaceuticals and personal care products (PPCPs) are increasingly being scrutinized by the scientific community due to their environmental persistence. Therefore, the development of novel environmentally compatible and energy-efficient technologies for their removal is highly anticipated. In this work, a novel metal-free photocatalytic nanoreactor was successfully synthesized by anchoring carbon dots to hollow carbon nitride nanospheres (HCNS/CDs). The unique structure of these hollow nanospherical HCNS/CDs hybrids endowed them with a high population of reactive sites, while enhancing optical absorption due to internal light reflection. Simultaneously, the CDs served as "artificial antennas" to absorb and convert photons with low energy, due to their superior up-converting properties. Consequently, the HCNS/CDs demonstrated excellent photodegradation activities for the degradation of PPCPs under broad-spectrum irradiation. Remarkedly, 10 mg/L of naproxen (NPX) was completely degraded following 5 min of natural solar irradiation. It was further revealed that the O2â¢- played a significant role during the photocatalytic process, which could lead to the decomposition of NPX. The effects of natural water matrices and the degradation of trace PPCPs further supported that this photocatalytic system may be efficaciously applied for the remediation of PPCPs contamination in ambient waterways.
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Nanosferas , Carbono , Catálisis , Cinética , Porosidad , AguaRESUMEN
Widespread usage of the sulfonamide class of antibiotics is causing increasing ecotoxicological concern, as they have the capacity to alter ambient ecosystems. Photocatalytic technology is an attractive yet challenging strategy for the degradation of antibiotics. For this work, the phosphate modification of m-Bi2O4 (Bi2O4-P) was prepared via a one-step hydrothermal process involving sodium bismuthate and sodium phosphate, which was employed for the degradation of sulfamethazine (SMZ) under visible light irradiation. The 0.5% Bi2O4-P exhibited excellent photocatalytic performance, which was 1.9 times that of pure m-Bi2O4. The photocatalytic degradation kinetics and mechanism of SMZ was investigated at different pH, whereupon it was revealed that m-Bi2O4-P exhibited improved SMZ adsorption and photocatalytic activities in contrast to pure m-Bi2O4. Compared with other four sulfonamide antibiotics, structures that contained additional methyl on the pyrimidine could be more easily attacked by phosphate modified m-Bi2O4. Reactive species (RS) scavenging experiments revealed that h+ was primarily responsible for the degradation of SMZ. Further studies of RS by ESR technology, and the results of photoelectrochemical properties showed phosphate-modified m-Bi2O4 could make greater use of photogenerated carriers, thereby producing additional RS. Based on the HRAM LC-MS/MS and the Frontier Molecular Orbital Theory, the degradation pathways of SMZ were proposed.