A comparison increasing the photodegradation power of a Ag/g-C3N4 /CoNi-LDH nanocomposite: Photocatalytic activity toward water treatment.

For environmental applications, it is crucial to rationally design and synthesize photocatalysts with positive exciton splitting and interfacial charge transfer. Here, a novel Ag-bridged dual Z-scheme Ag/g-C3N4/CoNi-LDH plasmonic heterojunction was successfully synthesized using a simple method, with the goal of overcoming the common drawbacks of traditional photocatalysts such as weak photoresponsivity, rapid combination of photo-generated carriers, and unstable structure. These materials were characterized by XRD, FT-IR, SEM, TEM UV-Vis/DRS, and XPS to verify the structure and stability of the heterostructure. The pristine LDH, g-C3N4, and Ag/g-C3N4/CoNi-LDH composite were investigated as photocatalysts for water remediation, an environmentally motivated process. Specifically, the photocatalytic degradation of tetracycline was studied as a model reaction. The performance of the supports and composite catalyst were determined by evaluating both the degradation and adsorption phenomenon. The influence of several experimental parameters such as catalyst loading, pH, and tetracycline concentration were evaluated. The current study provides important data for water treatment and similar environmental protection applications.

Constructing homo/hetero-nuclear carbon and oxygen atoms co-doped graphitic carbon nitride assisted by ionic liquid for photothermal synergistic catalytic oxidation of cyclohexane.

The adoption of photothermal synergistic catalysis for cyclohexane oxidation can balance the advantages of high conversion of thermal catalysis and high selectivity of photocatalytic technology to achieve better catalytic performance. Here, we prepared functional carbon nitride (BCA-CN) by self-assembly strategy of ionic liquid [Bmim]CA (1-Butyl-3-methylimidazole citrate) with melamine and cyanuric acid utilizing abundant elements and anionic/cationic hydrogen bonding interactions. The introduction of [Bmim]CA embeds C-C (carbon and carbon band) and C-O-C (ether bond) structures into graphitic carbon nitride (g-C3N4) framework, significantly improving light absorption capacity and migration of photo generated charge carriers. Compared to g-C3N4, both BCA-CN increases cyclohexane conversion and KA oil (the mixture of cyclohexanol and cyclohexanone) selectivity by 1.3 times under photothermal catalysis. The surface reactions are facilitated by changing adsorption sites of cyclohexane to increase adsorption energy and obtaining more hydroxyl radicals and superoxide radicals. Furthermore, the enhanced selectivity is attributed to the difficulty in generating cyclohexanone radicals. This work offers the reference scheme for the development of efficient photothermal catalysts in the selective oxidation of cyclohexane.

Boosted electrocatalytic activity and durability of CuFe/NC by modulating the interfacial composition and electronic structure for efficient oxygen reduction reaction.

Oxygen reduction reaction (ORR) serves as the foundation for various electrochemical energy storage devices. Fe/NC catalysts are expected to replace commercial Pt/C as oxygen electrode catalysts based on the structural tunability at the atomic level, abundant iron ore reserves and excellent activity. Nevertheless, the lack of durability and low active site density impede its advancement. In this work, a durable catalyst, CuFe/NC, for ORR was prepared by modulating the interfacial composition and electronic structure. The introduction of Cu nanoclusters partially eliminates the Fenton effect from Fe and optimizes the electron structure of FeNx, thereby effectively enhancing the long-term durability and activity. The prepared CuFe/NC exhibits a half-wave potential (E1/2) of 0.90 V and superior stability with a decrease in E1/2 of only 20 mV after 10,000 cycles. The assembled alkaline Zinc-Air batteries (ZABs) with CuFe/NC exhibit an open-circuit potential of 1.458 V. At a current density of 5 mA cm-2, the batteries are capable of operation for 600 h with a stable polarization. This CuFe/NC may promote the practical application of novel and renewable electrochemical energy storage devices.

Efficient photocatalytic H2O2 production and photodegradation of RhB over K-doped g-C3N4/ZnO S-scheme heterojunction.

Designing efficient dual-functional catalysts for photocatalytic oxygen reduction to produce hydrogen peroxide (H2O2) and photodegradation of dye pollutants is challenging. In this work, we designed and fabricated an S-scheme heterojunction (g-C3N4/ZnO composite photocatalyst) via one-pot calcination of a mixture of ZIF-8 and melamine in the KCl/LiCl molten salt medium. The KCN/ZnO composite produced 4.72 mM of H2O2 within 90 min under illumination (with AM 1.5 filter), which is almost 1.3 and 7.8 times than that produced over KCN and ZnO, respectively. Simultaneously, the KCN/ZnO also showed excellent photodegradation performance for the dye pollutants (Rhodamine B, RhB), with a removal rate of 92 % within 2 h. The apparent degradation rate constant of RhB over KCN/ZnO was approximately 5-8 times that of KCN and ZnO. In the photocatalytic process, photo-generated holes and superoxide radicals are the main active species. Oxygen (O2) was mainly reduced to produce H2O2 via a two-electron (2e-) pathway with superoxide radicals as intermediates and the 2e- oxygen reduction reaction selectivity of KCN/ZnO was close to 69.82 %. Photo-generated holes are mainly responsible for the degradation of RhB. Compared with pure KCN and ZnO, the enhanced photocatalytic activity of the KCN/ZnO composite is mainly attributed to the following aspects: 1) larger specific surface area and pore volume is beneficial to expose more active sites; 2) stronger light harvesting ability and red-shifted absorption edge bestow the compound a stronger light utilization efficiency; 3) the construction of S-scheme heterostructure between KCN and ZnO improve the photogenerated electron-hole pairs separation ability and bestow photogenerated carriers a higher redox potential.

Advancing antibiotic detection and degradation: recent innovations in graphitic carbon nitride (g-C3N4) applications.

The uncontrolled release of antibiotics into the environment would be extremely harmful to human health and ecosystems. Therefore, it is in urgent need to monitor the environment and promote the detection and degradation of antibiotics to the relatively harmless by-products to a feasible extent. Graphitic carbon nitride (g-C3N4) is a non-metallic n-type semiconductor that can be used for the antibiotic detection and degradation due to its easy synthesis process, excellent chemical stability and unique optical properties. Unfortunately, the utilization of visible light, electron-hole recombination and electron conductivity have hindered its potential applications in the fields of photocatalytic degradation and electrochemical detection. Although previous publications have highlighted the diverse modification methods for the g-C3N4-based materials, the underlying structure-performance relationships of g-C3N4, especially for the detection and degradation of antibiotics, remains to be further explored. In view of this, the current review centered on the recent progress in the modification techniques of g-C3N4, the detection and degradation of antibiotics using the g-C3N4-based materials, as well as the potential antibiotic degradation mechanisms of the g-C3N4-based materials. Additionally, the underlying applications of the g-C3N4-based materials for antibiotic detection and degradation were also prospected. This review would provide a valuable research foundation and the up-to-date information for the g-C3N4-based materials to combat antibiotic pollution in the environment.

Photocatalytic activity of self-heterojunctioned intermediate phases in HCl protonated and HNO3 deconjugated g-C3N4 nanostructures.

This research involved the different acid-treatment conditions of graphitic carbon nitride and its modified nanostructures through thermal polycondensation of urea at various temperatures. X-ray diffraction patterns revealed that processing at a lower temperature than 500 °C resulted in melem and its derivatives, indicating incomplete transformation of urea to g-C3N4. However, treatment at higher temperatures and the HCl acid treatment led to the formation and expansion of g-C3N4 networks, as evidenced by notable differences in peak intensities observed in their Fourier-transform infrared and Raman spectra. Scanning electron microscopy analysis illustrated a transition from the granular morphology of melamine to the layered structure characteristic of g-C3N4. The nanoparticle morphology observed in the HNO3 acid treatment sample was attributed to the deconjugation of nanosheets through the highly oxidative acid medium. The most suitable photocatalytic activity for Methylene Blue (MB) degradation under UV and visible light illumination was observed for the samples prepared at 550 °C and HCl post-processed nanostructures. It is proposed that the enhanced photocatalytic activity observed in these samples is most likely attributed to the reduced recombination of photogenerated charge carriers facilitated by heterojunctions formed between different intermediate phases. These findings highlight the potential of modified g-C3N4 and its derivatives as promising photocatalytic materials for water purification applications.

NAT10/ac4C/JunB facilitates TNBC malignant progression and immunosuppression by driving glycolysis addiction.

BACKGROUND: N4-Acetylcytidine (ac4C), a highly conserved post-transcriptional mechanism, plays a pivotal role in RNA modification and tumor progression. However, the molecular mechanism by which ac4C modification mediates tumor immunosuppression remains elusive in triple-negative breast cancer (TNBC). METHODS: NAT10 expression was analyzed in TNBC samples in the level of mRNA and protein, and compared with the corresponding normal tissues. ac4C modification levels also measured in the TNBC samples. The effects of NAT10 on immune microenvironment and tumor metabolism were investigated. NAT10-mediated ac4C and its downstream regulatory mechanisms were determined in vitro and in vivo. The combination therapy of targeting NAT10 in TNBC was further explored. RESULTS: The results revealed that the loss of NAT10 inhibited TNBC development and promoted T cell activation. Mechanistically, NAT10 upregulated JunB expression by increasing ac4C modification levels on its mRNA. Moreover, JunB further up-regulated LDHA expression and facilitated glycolysis. By deeply digging, remodelin, a NAT10 inhibitor, elevated the surface expression of CTLA-4 on T cells. The combination of remodelin and CTLA-4 mAb can further activate T cells and inhibite tumor progression. CONCLUSION: Taken together, our study demonstrated that the NAT10-ac4C-JunB-LDHA pathway increases glycolysis levels and creates an immunosuppressive tumor microenvironment (TME). Consequently, targeting this pathway may assist in the identification of novel therapeutic strategies to improve the efficacy of cancer immunotherapy.

Oxygen Vacancies Regulated S-Scheme Charge Transport Route in BiVO4-OVs/g-C3N4 Heterojunction for Enhanced Photocatalytic Performance.

Oxygen vacancies (OVs) are widely considered as active sites in photocatalytic reactions, yet the crucial role of OVs in S-scheme heterojunction photocatalysts requires deeper understanding. In this work, OVs at hetero-interface regulated S-scheme BiVO4-OVs/g-C3N4 photocatalysts are constructed. The Fermi-level structures of BiVO4 and g-C3N4 lead to a redistribution of charges at the heterojunction interface, inducing an internal electric field at the interface, which tends to promote the recombination of photogenerated carriers at the interface. Importantly, the introduction of OVs induces defect electronic states in the BiVO4 bandgap, creating indirect recombination energy level that serves as crucial intermediator for photogenerated carrier recombination in the S-scheme heterojunction. As a result, the photocatalytic degradation rate on Rhodamine B (RhB) and tetracyclines (TCs) for the optimal sample is 10.7 and 11.8 times higher than the bare one, the photocatalytic hydrogen production rate is also improved to 558 µmol g-1 h-1. This work shows the importance of OVs in heterostructure photocatalysis from both thermodynamic and kinetic aspects and may provide new insight into the rational design of S-scheme photocatalysts.

Construction of S-scheme g-C3N4/PbTiO3 heterojunction and its highly efficient photocatalytic degradation of organic pollutants under simulated sunlight.

This study successfully synthesized a composite photocatalyst g-C3N4/PbTiO3 through hydrothermal and calcination methods using PbTiO3 and g-C3N4. The catalyst was characterized by XRD, FTIR, Raman, XPS, SEM, TEM, UV-vis DRS, PL, and other techniques. The results indicate that the composite photocatalyst exhibits efficient electron transfer, enhanced light absorption, effective separation and utilization of photogenerated electron-hole pairs, demonstrating superior photocatalytic activity. Under simulated sunlight, the removal efficiency of methyl blue (MB) with an initial concentration of 10 mg/L reaches 93.0% after 120 min. After five cycles, the degradation efficiency of MB is 79.2%, still maintaining 85% of the initial catalytic activity. The pH values in the range of 4.0-7.0, inorganic anions, and water quality have a minimal impact on the photocatalytic degradation of MB. Additionally, the composite photocatalyst exhibits strong removal capabilities for other pollutants, such as tetracycline. Therefore, the prepared catalyst demonstrates good feasibility for practical applications. Free radical quenching experiments indicate that hydroxyl radicals (·OH) are the primary active groups in the photocatalytic degradation of MB. Based on this, a photocatalytic mechanism involving a S-scheme heterojunction has been proposed. This study provides new insights into preparing PbTiO3 composite semiconductors and constructing novel S-scheme heterojunctions.

Transesterification of waste cooking oil for biodiesel production using alkaline-modified graphitic carbon nitride heterogeneous catalyst.

Developing efficient, stable, cost-effective, and environmentally benign heterogeneous catalysts for transesterification is highly required for sustainable biodiesel production. The present study explores the biodiesel production from waste cooking oil (WCO) using graphitic carbon nitride (g-C3N4) and its alkaline-modified nanocatalyst. The catalysts were characterised by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Energy Dispersive X-ray spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR). From the XRD analysis, crystalline sizes of g-C3N4 and alkaline g-C3N4 were found to be 26 and 29 nm, respectively. Transesterification of WCO was carried out at 60 °C for a reaction time of 2 h using 2 wt.% of g-C3N4 and alkaline g-C3N4. Transesterification reaction catalysed by alkaline-modified g-C3N4 was found with a higher yield of biodiesel (89%) than the biodiesel yield (78%) with transesterification reaction catalysed by g-C3N4. The recyclability of both catalysts was also evaluated by reusing them for up to the 5th cycle. The obtained biodiesel was analyzed by using FTIR and GC-MS. The synthesised biodiesel was found to have significant level of monounsaturated fatty acids and saturated fatty acids, which make it usefuel for use as fuel. Some physicochemical properties of the obtained biodiesel were also calculated and found appropriate as per the American Society for Testing and Materials (ASTM) standards. With high reusability and good catalytic activity, the synthesised alkaline-modified g-C3N4 can be employed as a viable option for biodiesel production from WCO.

MoS2high temperature sensitive element with a single Si3N4protective layer.

Temperature sensors find extensive applications in industrial production, defense, and military sectors. However, conventional temperature sensors are limited to operating temperatures below 200°C and are unsuitable for detecting extremely high temperatures. In this paper, a method for thermal protection of molybdenum disulfide (MoS2) films is proposed and a MoS2 high temperature sensor is prepared. By depositing a monolayer of Si3N4 onto MoS2, not only is the issue of high-temperature oxidation effectively addressed, but also the contamination by impurities that could potentially compromise the performance of MoS2 is prevented. Moreover, the width of the Schottky barrier of metal/MoS2 is reduced by using PECVD deposition of 400 nm Si3N4 to form an ohmic contact, which improves the electrical performance of the device by three orders of magnitude. The sensor exhibits a positive temperature coefficient measurement range of 25 to 550°C, with a maximum temperature coefficient of resistance (TCR) of 0.32%·°C-1. The thermal protection method proposed in this paper provides a new idea for the fabrication of high-temperature sensors, which is expected to be applied in the high-temperature field. .

Micron-Scale Vertical MoS2/Porous g-C3N4 Piezocatalyst via a Precursor's Supramolecular Self-Template Architecture: Degradation and Hydrogen Evolution.

Piezocatalysis can effectively harvest various kinds of mechanical energy with high entropy from the environment and drive some redox reactions without light irradiation, where MoS2- and g-C3N4-based piezocatalysts are recent research hotspots. This study constructs an architecture of ordered melamine hydrochloride-cyanuric acid/MoO42- supramolecular precursor via self-assembly, serving as a self-template for in situ tight growth of vertically aligned micron-scale MoS2 on porous foam-like g-C3N4(CMx) under S vapor with a bioinspired rooting and sprouting-like process. Experiments, DFT calculations, and finite element simulations collectively confirm the high piezoresponse of the CMx with high exposure of active sites and enhanced mechanical energy collection. The vertical interfaces and built-in electric fields in the composite induce efficient charge carrier separation and transfer. The optimized CM0.77 efficiently degrades various organic dyes and antibiotic under dark ultrasound [rhodamine B (RhB): 0.47 s-1, methyl orange (MO): 0.05 s-1, methylene blue (MB): 0.21 s-1, and tetracycline hydrochloride (TC): 0.03 s-1] and achieves hydrogen evolution (2431 µmol·g-1·h-1). Under simulated water flow (10 L/min), the expanded CM0.77/Al2O3 porous foam ceramic (CM/alumina ceramic) purifier device degrades 95% of 400 mL of RhB within 25 min. The developed ordered vertical MoS2/g-C3N4 piezocatalyst demonstrates rapid pollutant degradation and efficient hydrogen evolution under water flow and ultrasound, providing new insights for constructing multidimensional piezoelectric composites for environmental remediation and clean energy production.

Air stability of monolayer WSi2N4 in dark and bright conditions.

Two-dimensional materials with chemical formula MA2Z4 are a promising class of materials for optoelectronic applications. To exploit their potential, their stability with respect to air pollution has to be analyzed under different conditions. In a first-principle study based on density functional theory, we investigate the adsorption of three common environmental gas molecules (O2, H2O, and CO2) on monolayer WSi2N4, an established representative of the MA2Z4 family. The computed adsorption energies, charge transfer, and projected density of states of the polluted monolayer indicate a relatively weak interaction between substrate and molecules resulting in an ultrashort recovery time of the order of nanoseconds. O2 and water introduce localized states in the upper valence region but do not alter the semiconducting nature of WSi2N4 nor its band-gap size apart from a minor variation of a few tens of meV. Exploring the same scenario in the presence of photogenerated electrons and holes, we do not notice any substantial difference except for O2 chemisorption when negative charge carriers are in the system. In this case, monolayer WSi2N4 exhibits signs of irreversible oxidation, testified by an adsorption energy of -5.5 eV leading to an infinitely long recovery time, a rearrangement of the outermost atomic layer bonding with the pollutant, and n-doping of the system. Our results indicate stability of WSi2N4 against H2O and CO2 in both dark and bright conditions, suggesting the potential of this material in nanodevice applications.

Photoirradiation-enhanced behavior via morphological manipulation of CoFe2O4/g-C3N4 heterojunction for supercapacitor and CO2 reduction.

Regulating the morphology of graphitic carbon nitride (g-C3N4, CN) and constructing CoFe2O4/g-C3N4 (CFO/CN) heterojunctions were adopted in the photocatalytic energy storage and photocatalytic CO2 reduction (PCR). CFO/CNS had outstanding light response ability, while CFO/CNT possessed excellent charge transfer ability. Consequently, CFO/CNT electrode exhibited the highest specific capacitance without light, CFO/CNS electrode showed the most obvious photo-enhanced capacitance behavior with an increase by 21.05 % under light. This was ascribed to the generation and separation of photo-generated carriers, promoting oxidation/reduction reactions. And in PCR, the electron consumption rates of four CFO/CN heterojunctions were CFO/CNT > CFO/BCN > CFO/MCN > CFO/CNS. CFO/CNT presented the highest photocatalytic activity, attributing to the strong redox ability and photo-enhanced electron transfer. This strategy of utilizing CFO/CN heterojunctions to construct photo-enhanced supercapacitor electrodes and photocatalytic CO2 reduction catalysts provided new ideas for energy conversion and storage.

Antifouling characteristics and mechanisms in visible-light photocatalytic membrane bioreactor based on g-C3N4 modified membrane.

A novel visible-light photocatalytic membrane bioreactor (R3) was constructed for membrane fouling control and effluent quality improvement. Specially, g-C3N4 modified membrane was evaluated for the performance of synergistic separation and photocatalysis. Another two parallel reactors, MBRs with ceramic membrane (R1) and g-C3N4 membrane in dark condition (R2), were operated synchronously for comparison. A satisfactory effluent quality was obtained in R3 with COD and NH4+-N around 22.0 mg/L and 1.02 mg/L during 60-day operation, which was superior to R1 (27.8, 1.42 mg/L) and R2 (29.9, 2.26 mg/L). The thickness of cake layer on membranes in R3 (2.46 µm) was thinner than R1 (3.52 µm) and R2 (4.97 µm) after operation, indicating the introduction of visible light could effectively mitigate membranes fouling. Moreover, microorganism community analysis revealed that visible light increased the relative abundance of Bacteroidetes and Chryseolinea, which not only enhanced the activity of microorganisms in metabolizing organic nutrients, but also improved the transfer and utilization of photogenerated electrons on the semiconductor-microorganism interface. The active aromatic protein metabolism and the upregulated related enzymes further demonstrated the synergistic effect of photocatalysis and microbial communities on the membrane fouling mitigation. This work provides a novel application of photocatalysis into antibiofouling effect in MBRs, and opens a strategy for bacteria inactivation and foulants removal with eco-friendly solar energy.

Promising metal-free green heterogeneous catalyst for quinoline synthesis using Brønsted acid functionalized g-C3N4.

Rationally designing distinct acidic and basic sites can greatly enhance performance and deepen our understanding of reaction mechanisms. In our current investigation, we studied the utilization of Brønsted acid sites within layered graphitic carbon nitride (g-C3N4) for the first time to enhance the rate of the Friedländer synthesis. The structural and surface analyses confirm the effective integration of -COOH and -SO3H groups into the g-C3N4 lattice. The surface-functionalized g-C3N4-CO-(CH2)3-SO3H exhibits a remarkable acceleration in quinoline formation, surpassing previously mentioned catalysts, and demonstrating notable recyclability under optimized mild reaction conditions. The heightened reaction rate observed over g-C3N4-CO-(CH2)3-SO3H is attributed to its elevated surface acidity. By probing the Friedländer reaction mechanism through surface characterization, examination of reaction intermediates, and investigation of substrate scope, we elucidate the pivotal role of Brønsted acid sites. This study constitutes a comprehensive exploration of metal-free heterogeneous catalysts for the Friedländer reaction, offering a unique contribution to the field.

Oxygen Vacancy Engineering and Constructing Built-In Electric Field in Fe-g-C3N4/Bi2MoO6 Z-Scheme Heterojunction for Boosting Photo-Fenton Catalytic Degradation Performance of Tetracycline.

A novel Fe-g-C3N4/Bi2MoO6 (FCNB) Z-scheme heterojunction enriched with oxygen vacancy is constructed and employed for the photo-Fenton degradation of tetracycline (TC). The 2% FCNB demonstrates prominent catalytic performance and mineralization efficiency for TC wastewater, showing activity of 8.20 times greater than that of pure photocatalytic technology. Density-functional theory (DFT) calculations and degradation experiments confirm that the formation of Fe-N4 sites induces spin-polarization in the material, and the difference in Fermi energy levels results in the formation of built-in electric field at the contact interface, which facilitates the continuous generation and migration of photogenerated carriers to address the issue of insufficient cycling power of Fe (III)/Fe (II).The reactive radicals persistently target the extremely reactive sites anticipated by the Fukui function, causing the mineralization of TC molecules into "non-toxic" compounds through processes of hydroxylation, demethylation, and deamidation. This work holds significant importance in the domain of eliminating organic pollutants from water.

Peroxymonosulfate-assisted photocatalysis system enhanced magnetic Fe3O4@P-C3N4 treatment of tetracycline wastewater: Multi-pathways mediated electrons migration to generate reactive species.

Photocatalytic wastewater purification is essential for environmental remediation, but rapid carrier recombination and limited oxidative capacity hinder progress. This study proposes an innovative strategy by integrating homogeneous and heterogeneous electron acceptors into a g-C3N4-based photocatalytic system, significantly enhancing the multipath utilization of photogenerated electrons. A novel Fe3O4@P-C3N4 was developed to activate an advanced peroxymonosulfate-assisted photocatalysis (PAP) system, achieving complete degradation and significant mineralization of tetracycline (TC) in real water environments, outperforming others reported in the last five years. Phytic acid, as a key precursor, modifies the hollow tubular morphology and introduces phosphorus (P) heteroatoms as electronic trapping centers, enhancing the visible light response and carrier separation, thereby promoting the Fe2+/Fe3+ cycle and the formation of reactive species. Density functional theory (DFT) calculations pinpointed TC's vulnerable sites and synergically identified reactive species, revealing almost non-toxic degradation processes. Moreover, the recyclable magnetic Fe3O4@P-C3N4/PAP system demonstrates practical application potential and leaching stability in cyclic and continuous testing. This study offers unique insights into the strategic design of photocatalysts and catalytic environments, potentially advancing practical wastewater remediation.

In Vitro and In Vivo Assessments of Newly Isolated N4-like Bacteriophage against ST45 K62 Capsular-Type Carbapenem-Resistant Klebsiella pneumoniae: vB_kpnP_KPYAP-1.

The rise of carbapenem-resistant Klebsiella pneumoniae (CRKP) presents a significant global challenge in clinical and healthcare settings, severely limiting treatment options. This study aimed to utilize a bacteriophage as an alternative therapy against carbapenem-resistant K. pneumoniae. A novel lytic N4-like Klebsiella phage, vB_kpnP_KPYAP-1 (KPYAP-1), was isolated from sewage. It demonstrated efficacy against the K62 serotype polysaccharide capsule of blaOXA-48-producing K. pneumoniae. KPYAP-1 forms small, clear plaques, has a latent period of 20 min, and reaches a growth plateau at 35 min, with a burst size of 473 plaque-forming units (PFUs) per infected cell. Phylogenetic analysis places KPYAP-1 in the Schitoviridae family, Enquatrovirinae subfamily, and Kaypoctavirus genus. KPYAP-1 employs an N4-like direct terminal repeat mechanism for genome packaging and encodes a large virion-encapsulated RNA polymerase. It lacks integrase or repressor genes, antibiotic resistance genes, bacterial virulence factors, and toxins, ensuring its safety for therapeutic use. Comparative genome analysis revealed that the KPYAP-1 genome is most similar to the KP8 genome, yet differs in tail fiber protein, indicating variations in host recognition. In a zebrafish infection model, KPYAP-1 significantly improved the survival rate of infected fish by 92% at a multiplicity of infection (MOI) of 10, demonstrating its potential for in vivo treatment. These results highlight KPYAP-1 as a promising candidate for developing phage-based therapies targeting carbapenemase-producing K. pneumoniae.

Antibacterial and Anticorrosive Hydrogel Coating Based on Complementary Functions of Sodium Alginate and g-C3N4.

Graphitic carbon nitride (g-C3N4, CN) has emerged as a promising photocatalytic material due to its inherent stability, antibacterial properties, and eco-friendliness. However, its tendency to aggregate and limited dispersion hinder its efficacy in practical antibacterial applications. To address these limitations, this study focuses on developing a composite hydrogel coating, in which sodium alginate (SA) molecules interact electrostatically and through hydrogen bonding to anchor CN, thereby significantly improving its dispersion. The optimal CN loading of 35% results in a hydrogel with a tensile strength of 120 MPa and an antibacterial rate of 99.87% within 6 h. The enhanced mechanical properties are attributed to hydrogen bonding between the -NH2 groups of CN and the -OH groups of SA, while the -OH groups of SA facilitate the attraction of photogenerated holes from CN, promoting carrier transfer and separation, thereby strengthening the antibacterial action. Moreover, the hydrogel coating exhibits excellent antibacterial and corrosion resistance capabilities against Pseudomonas aeruginosa on 316L stainless steel (316L SS), laying the foundation for advanced antimicrobial and anticorrosion hydrogel systems.