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Abstract Novel Zr 2 Ni 1 Cu 7 trimetallic nano-alloy (TNA) and Zr 2 Ni 1 Cu 7 /Si 3 N 4 trimetallic nano-alloy composite (TNAC) have been successfully prepared by facile microwave reduction method. The synthesis of TNA and TNAC was ascertained by characterizing them by using various techniques such as SEM, TEM, XRD, EDX and FTIR etc. The EDX shows the presence of all constituents in TNA and TNAC. The XRD study demonstrated the crystalline and semi-crystalline nature of TNA and TNAC. The optical band gap study revealed that TNAC (2.47 eV) has lower band gap then TNA (2.54 eV). The visible light photocatalytic activity of Zr 2 Ni 1 Cu 7 TNA and Zr 2 Ni 1 Cu 7 /Si 3 N 4 TNAC has been successfully utilized for the photodegradation of methylene blue (MB). The presence of H 2 O 2 has been found to influence the photodegradation rate. Photodegradation results presented that maximum degradation was observed in the presence of H 2 O 2 and Zr 2 Ni 1 Cu 7 TNAC (92%). Scavenging activity has revealed that the hydroxyl radicals were the major reacting species. These species successfully degraded the MB into various intermediates that has successfully been determined by the LC-MS. Kinetic studies indicated that the degradation of MB by Zr 2 Ni 1 Cu 7 TNA and Zr 2 Ni 1 Cu 7 /Si 3 N 4 TNAC followed pseudo-first-order kinetics. Graphical abstract Unlabelled Image Highlights • Zr 2 Ni 1 Cu 7 TNA and Zr 2 Ni 1 Cu 7 /Si 3 N 4 TNAC synthesized by facile microwave reduction method. • Synthesis of TNA and TNAC were ascertained by characterizing them with SEM, TEM, XRD, EDX and FTIR. • The optical band gap study revealed that TNAC(2.47 eV) has lower band gap then TNA (2.54 eV) • TNA and TNAC were successfully employed for the photodegradation of methylene blue. [ABSTRACT FROM AUTHOR]

• g-C 3 N 4 and MOFs based heterojunctions –synthesis routes and advantages. • Types of g-C 3 N 4 and MOFs heterojunctions were discussed-modification strategies. • g-C 3 N 4 and MOFs based heterojunctions for photocatalytic environmental remediation and energy production. • Conclusion and future research prospects on g-C 3 N 4 and MOFs based on heterojunctions. Photocatalytic technology has emerged as a promising solution for environmental remediation and energy production, and the development of efficient and stable photocatalysts is of great importance. Recent advances in g-C 3 N 4 /Metal Organic Frameworks (MOFs) heterojunctions have shown excellent potential in achieving high-performance photocatalytic environmental remediation and energy production. In this review, we have summarized the recent advances in the design and synthesis of g-C 3 N 4 /MOFs heterojunctions and their application in photocatalytic environmental remediation and energy production. We have discussed the advantages and challenges of g-C 3 N 4 /MOFs heterojunctions, such as enhanced light absorption, increased surface area, and improved electron-hole separation, and their effects on photocatalytic performance. We also highlight the recent research progress in the utilization of g-C 3 N 4 /MOFs heterojunctions for various environmental remediation applications, including the degradation of organic pollutants and the removal of heavy metals, as well as for energy production applications such as hydrogen evolution and CO 2 reduction. Furthermore, we provide an overview of the latest theoretical and experimental investigations into the mechanisms of photocatalysis in g-C 3 N 4 /MOFs heterojunctions, which can help to guide the rational design of high-performance photocatalysts. Our analysis of the literature reveals that g-C 3 N 4 /MOF heterojunctions have demonstrated excellent photocatalytic activity for the degradation of various pollutants, such as methyl orange, rhodamine B, and bisphenol A. For instance, a g-C 3 N 4 /ZIF-8 heterojunction achieved a photocatalytic degradation rate of 99.9% for methyl orange under visible light irradiation within 60 min. Moreover, the g-C 3 N 4 /MOF heterojunctions have also been found to be efficient in water splitting for hydrogen production. For instance, a g-C 3 N 4 /UiO-66 heterojunction achieved a hydrogen production rate of 1260 μmol h−1g−1 under visible light irradiation. The recent data on the advances in g-C 3 N 4 /MOFs heterojunctions demonstrate their enormous potential for practical applications in photocatalytic environmental remediation and energy production. [ABSTRACT FROM AUTHOR]

Rationally fabricated Z -scheme hetero-junctions with intimate interfacial contact have proven to accelerate the photocatalytic degradation of noxious pollutants by effectively suppressing the recombination and promoting charges transfer rate. Herein, we report fabrication of reduced graphene oxide (RGO) modified LaTiO 2 N/Bi 2 S 3 heterojunction photocatalyst by sovothermal route. The microstructure analysis, structure determination, electronic and optical analysis of as prepared photocatalysts was done by using multiple techniques. The Z -scheme LaTiO 2 N/Bi 2 S 3 @RGO (LBR) photocatalyst shows remarkable performance for photo-degradation of tetracycline (TC) under visible light. 96.4% TC was eliminated within 90 min under visible light with ~100% removal in 60 min under full spectrum irradiation. In addition the heterojunction shows 80.2% TC removal under natural sunlight irradiation. The TC degradation with LBR heterojunction is ~9 times faster than bare Bi 2 S 3. The Z -scheme transfer follows the route as Bi 2 S 3 → RGO → LaTiO 2 N and provides a swift path for movement of electrons from CB of LaTiO 2 N to VB of Bi 2 S 3. The possible degradation route of TC has also been proposed based on quenching experiments and identification of degradation intermediates by Liquid chromatography-mass spectrometry (LC-MS). The quenching experiments reveal that O 2 – radicals are the main active species involved followed by OH radicals which has been explained by thermodynamic feasibility of their production from the junction arrangement. The mechanism has been explained by Z -scheme transfer by comparing to the conventional type-II junction. The enhancement in photocatalytic activity is primarily attributed to Z-scheme charge transfer between LaTiO 2 N and Bi 2 S 3 facilitated by reduced graphene oxide sheet via strong interfacial contact maintaining high potential for redox conversions. The recycling experiments reveal the stability and reusability of the LBR hybrid photocatalyst with ability to perform under sunlight. The novel nitrides-phosphide based junction with improved properties for visible and solar photocatalytic activity provides future prospects in forming superior hetero-structures for environmental remediation. Unlabelled Image • LaTiO 2 N/Bi 2 S 3 @RGO heterojunction photocatalyst fabrication by simple solvothermal route. • High performance degradation of tetracycline-visible, full spectrum and sunlight • Interfacial charge transfer capacity-internal electric field–higher spectral capture. • Z-scheme and RGO lead to high charge separation, high redox capability, stability. • Thermodynamic feasibility and experimental findings suggest Z-scheme over conventional type-II transfer. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride based photocatalytic materials have proved to be one of most promising candidates for hazardous pollutant removal and clean energy production. Structural modification and engineering of various materials based on g-C 3 N 4 have been attempted to achieve solar energy harvesting, slow charge transfer and efficiency. Here we report synthesis of all metal free self-assembled carbon quantum dots and reduced graphene oxide layers modified S@g-C 3 N 4 /B@g-C 3 N 4 (CRSB) photocatalyst for visible and solar degradation of chloramphenicol (CMP) (10 mg L−1). Differently doped g-C 3 N 4 with different band structure forms a junction which grows into an effective Z -scheme photocatalyst. Extended visible absorption is achieved with optimized modification by reduced graphene oxide (RGO) and carbon quantum dots. The optical response, band structure and charge separation efficiency were tested by optical absorption, electrochemical impedance, Mott-Schottky plots and photo-luminescence. CQDs convert a typical type-II mechanism into effective Z -scheme transfer. For the best sample CRSB 99.1% CMP was photo-degraded in 90 min exposure to visible light and retention of high activity in natural solar light (92.4% in 120 min). A stable heterojunction has been attempted to design using boron doped g-C 3 N 4 and sulphur doped g-C 3 N 4 with different band positions via ratio optimization with enhanced charge transfer. The degradation rate for CRSB (0.0810 min−1) is 10 times than bare g-C 3 N 4 (0.00802 min−1). The optimized combination of carbon quantum dots and RGO with intimate interfacial contact for charge flow & reduced recombination, better adsorption of pollutant, high visible absorption and production of reactive oxygen species. The effect of pH, electrolytes and water matrix was studied for CMP degradation. The mechanism of degradation and mineralization was confirmed by liquid chromatography-mass spectrometry (LC-MS) analysis, scavenging experiments and electron spin resonance. It was observed that the chances of •O 2 – and •OH radicals increased on the formation of the junction as compared to individual doped and bare carbon nitride. The mineralization was ensured by high total organic removal and cyto-toxicity studies of treated water sample onto human peripheral blood (PBL) cells with high cell viability equivalent to untreated cells. This experiment supports the competence of optimally designed metal free and environmentally friendly cost-effective catalysts with higher photocatalytic efficiency for removal of hazardous pollutants. Unlabelled Image • S@g-C 3 N 4 and B@g-C 3 N 4 self-assembled junction • Heterojunction formed from differently doped g-C 3 N 4 • Modification by RGO and CQDs- All metal free catalyst • Intimate charge transfer at the interface-low recombination • Excellent visible and solar degradation of chloramphenicol • High mineralization-no toxicity on human blood cells [ABSTRACT FROM AUTHOR]

The development of multifunctional materials, specially nanocomposites, exhibit new and interesting properties which can extend the applicability ranges to diverse fields. In this way, the use of tri metallic nanoparticles, and derives, demonstrated higher efficacy for purification, catalytic activities and as antibacterial agents. This work is concentrated on the fabrication of Fe/La/Zn trimetallic nanoparticles (TNPs) and Fe/La/Zn@GO trimetallic nanocomposite (TNC) using the micro-emulsion method, specially indicated as photocatalysts for remediation of the organic pollutant. An intense characterization was performed by employing techniques as scanning electron microscopy (SEM), X-Ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). The potential applications of the Fe/La/Zn TNPs and Fe/La/Zn@GO TNC were explored for the photodegradation of phenylhydrazine in the presences of sunlight. Furthermore, the photocatalytic studies were performed under different conditions: (a) adsorption (in dark) followed by photocatalysis, and (b) simultaneously adsorptional-photocatalysis straight way in sunlight. It was observed that a reduction of 52% and 57.91% was achieved under sunlight using Fe/La/Zn TNPs and Fe/La/Zn@GO TNC, respectively. The optical band gap of Fe/La/Zn TNPs, and Fe/La/Zn@GO TNCs was found 2.73 eV and 2.30 eV, which lies in semiconductor region. On the other hand, the antimicrobial nature of TNPs and TNC was checked for E. coli and S. aureus. The inhibition zone exhibited a maximum at 150 μg/mL for Fe/La/Zn TNPs (19 mm), and Fe/La/Zn@GO TNC (17 mm). This study revealed that resulting materials can be defined as a novel class of advanced multifunctional materials which can be employed effectively for environmental remediation and antimicrobial studies. Unlabelled Image • Synthesis of Fe/La/Zn trimetallic nanoparticles (TNPs) and Fe/La/Zn@GO trimetallic nanocomposite (TNC) by micro emulsion way • Photodegradation of phenylhydrazine using Fe/La/Zn trimetallic nanoparticles and Fe/La/Zn@GO trimetallic nanocomposite • Photodegradation of 52% and 57.91% was achieved using Fe/La/Zn TNPs and Fe/La/Zn@GO TNC, respectively. • The optical band gap of Fe/La/Zn TNPs and Fe/La/Zn@GO TNCs was found to be 2.73 eV and 2.30 eV. • Antimicrobial nature of TNPs and TNC was checked beside E. coli and S. aureus. [ABSTRACT FROM AUTHOR]

In the present work, we synthesized La/Cu/Zr trimetallic nanoparticles (TNPs) by microwave method, which is applied as an effective nanophotocatalyst for the removal of a ampicillin antibiotic from aqueous media. The prepared nanomaterial was characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The experimental results showed that prepared nanoparticles have high photodegradation tendency for the removal of ampicillin antibiotic from the aqueous solution. The pseudo-first-order equation represents the better kinetics of the photocatalytic process. The feasibility of ampicillin antibiotic adsorption onto La/Cu/Zr TNPs was also studied and the results showed that the adsorption was supported with spontaneous photodegradation process. A photocatalytic degradation 86% of the antibiotic has been observed. [ABSTRACT FROM AUTHOR]