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In this work, the performance of a series of noble metal catalysts supported on the SBA-16 mesoporous matrix was studied. Its activity was measured in catalytic hydrotreating (HDT) reactions, such as tetralin hydrogenation in a batch reactor. The results were adjusted with a pseudo first order equation and then, the most active catalysts were tested in a continuous flow reactor under industrial-like conditions. Noble metal catalysts were synthesized, mainly monometallic iridium and bimetallic iridium-platinum and iridium-palladium supported SBA-16. The support was also modified with aluminum to provide Bronsted and Lewis acidity to the catalysts. All the catalysts were characterized by FTIR, XRD, NMR, N2 isotherms, H2 chemisorption, TPR and XPS to be able to relate the activity with the nature of the catalyst. The catalyst modified with 0.5 wt% of Ir, 0.5 wt% of Pt and 3 wt% of Al supported over SBA-16 matrix was the most active in tetralin hydrogenation to decalins in a Batch reactor, achieving the higher kinetic constant of 0.012 min−1 and 90% of conversion to fully hydrogenated decalins at 120 min of reaction time. This catalyst also was the most active in the hydrogenation of tetralin using a continuous flow reactor obtaining the highest kinetic constant of all the catalysts tested with a value of 0.152 mol/h g cat. and achieving 90% of conversion to decalins at W/F = 150. Its greater activity was explained in terms of greater hydrogenating capacity, better dispersion of the active species, and greater resistance to deactivation thanks to the protective effect of the bimetallic alloy formed in synergy with a greater acidity of the aluminum-modified support. In this work, optimization has been achieved in the synthesis of an active, selective, contaminant-resistant catalyst with great stability. Very good results were obtained in a continuous process under conditions like to industrial ones. [ABSTRACT FROM AUTHOR]

The design and development of bifunctional heterogeneous catalysts via interface engineering are a very promising and necessary strategy for constructing highly efficient water electrolyzers. Nevertheless, it remains a great challenge to devolve active catalyst centers for simultaneous activities of oxygen/hydrogen evolution reactions (OER/HER). Herein, an amorphous FeOOH ultrathin nanosheet is grown over crystalline NiCo2S4/Ni3S2 vertically aligned nanosheets (NS) onto a nickel foam (NF) substrate (denoted as FeOOH/NCS/NS/NF) using facile wet chemical approaches. The developed heterogeneous catalyst exhibits superior bifunctional electrocatalytic activities with the lowest overpotentials of 285 mV (OER) and 226 mV (HER) to realize 50 mA cm–2 in alkaline conditions. Consequently, coupling of amorphous FeOOH and crystalline NiCo2S4/Ni3S2 promotes the surface adsorption of oxygen intermediate species along with water dissociation on catalytic active centers and mass transport with electron transfer at the interface. In the alkaline electrolyzer system, the obtained heterogeneous electrode delivers a substantial overall water splitting performance with a small cell voltage of 1.55 (1.70) V to reach 10 (50) mA cm–2, where FeOOH/NCS/NS/NF is used as an anode and cathode. Thus, the proposed heterogeneous catalyst strategy validates the effective pathway to design a competent electrode for water electrolysis applications. [ABSTRACT FROM AUTHOR]

Objective(s): Electrochemical estimation of dopamine by synthesized Pd@Au-PANI nanocomposite. Materials and Methods: Au-doped and Au-Pd incorporated PANI nanocomposites were prepared via oxidative polymerization and hydrothermal methods with ammonium persulphate. Results: As-suggested biosensor was improved for the simultaneous disclosure of dopamine and hydroquinone, displayed low detection limits of 0.46 µM for dopamine and 0.23 mM for hydroquinone. Conclusion: The fabricated biosensor showed broad linear ranges for dopamine (5-25 µM), and hydroquinone (0.5-2.5 mM). Along with these good results, the Au-Pd@PANI nanotube also implemented good stability and reproducibility. [ABSTRACT FROM AUTHOR]

Aluminum castings are increasingly being used in automotive powertrain and structural applications for vehicle lightweighting. Cast aluminum parts often need to be machined and joined to steel components in multi-material systems. Bimetallic components produced by casting aluminum over steel substrate are advantageous due to the elimination of machining and traditional dissimilar material joining processes. However, forming a strong metallurgical bonding during overcasting process has been challenging. In this paper, the effects of processing conditions such as substrate surface preparation, pre-heating temperature, melt conditions as well as casting design were studied by investigating the bimetallic interfaces for aluminum A319 casting alloy and a high alloy steel substrate in a sand-casting process. Zn and Al-based substrate coatings were evaluated. The experimental results suggest a metallurgical bond between aluminum and steel can be formed during the sand-casting process via high temperature diffusion with or without coatings. Al-based substrate coating prior to overcasting results in the formation of a continuous layer of intermetallics at the bimetallic interface, with large Al–Si–Fe intermetallics penetrating the cast aluminum. [ABSTRACT FROM AUTHOR]

Static self‐assembly resides in thermodynamically stable global minima of the energy landscape, whereas dynamic self‐assembly occupies local minima of the energy profile and remains in the ordered state for a limited time via dissipation of energy to surroundings. This makes the spatiotemporal control over the assembly and disassembly mechanism easily controllable in the case of dynamic self‐assembly. However, due to the higher thermal stability of static self‐assembly, it is very challenging to perform reverse engineering on these types of systems. Herein we report growth reaction‐based reversal of static silver cubes obtained via cucurbit[8]uril (CB[8]) crosslinked self‐assembly of silver nanoparticles (AgNP). The AgNP building units with variable CB[8] surface coverage have been used as seeds onto which deposition of gold via growth reaction has been performed. The disassembly of supracube structure has been controlled by the formation of [AuCl4]−–CB[8] complex and successive reduction of [AuCl4]− to Au0 on the surface of the seed. The resulting monodispersed isotropic nanoparticles, formed from the CB[8] based cubic self‐assembly after growth, exhibit Au−Ag bimetallic nature. Quenching of the fluorogenic response from the hydrophobic dye coumarin‐7, added after growth, suggests direct interaction with the metallic nanoparticle surface after disassembly and thereby confirms successful growth reaction mediated reversal of self‐assembly. [ABSTRACT FROM AUTHOR]

Synthesis of unique morphologies in photocatalytic materials, coupled with utilization of wide-spectrum solar energy through rare earth doping, holds significant promise to maximize the potential of photocatalysts. Herein in, cube-like Holmium (Ho) doped Bi 5 Nb 3 O 15 was synthesized by the hydrothermal method and integrated with reduced graphene oxide (rGO) sheets. As synthesized Ho–Bi 5 Nb 3 O 15 @rGO composite along its analogs i.e., Bi 5 Nb 3 O 15 and Ho–Bi 5 Nb 3 O 15 was characterized by XRD, SEM, FT-IR, TGA, I–V, EIS, Mott-Schottky and photo-current measurements. Phase studies showed that crystallite size for Bi 5 Nb 3 O 15 , Ho–Bi 5 Nb 3 O 15 , and Ho–Bi 5 Nb 3 O 15 @rGO was 27.4, 25.5, and 13.5 nm, respectively. Optical analysis exhibited a reduction in the band gap in consequent to Ho doping from 2.54 to 2.19 eV for Ho–Bi 5 Nb 3 O 15. Conductivity and photo-current measurements showed a remarkable increase in both electrical conductivity and photo-response of Ho–Bi 5 Nb 3 O 15 upon its incorporation into rGO matrix, reaching maximum values of 1.72 × 10−2 S/m and 0.66 μA, respectively. The enhanced photocatalytic activity of Ho–Bi 5 Nb 3 O 15 @rGO was ensured through the outstanding photo-degradation efficiency (96.5 %) against crystal violet (CV), greater than Bi 5 Nb 3 O 15 (49 %) and Ho–Bi 5 Nb 3 O 15 (63.4 %). Additionally, Ho–Bi 5 Nb 3 O 15 @rGO showed sufficient potential towards the degradation of acetylsalicylic acid (ASA) with 79.1 % photo-degradation. This elevated photocatalytic activity of Ho–Bi 5 Nb 3 O 15 @rGO is believed to be contributed by the collaborative outcomes aroused from the Ho-doping and heterojunction fabrication among cubical Ho–Bi 5 Nb 3 O 15 and rGO sheets. Hence, our work proposes an efficient strategy for the development of innovative photolytic materials for sustainable wastewater remediation. [ABSTRACT FROM AUTHOR]

Colloidal metal nanoparticles exhibit interesting catalytic properties for the hydrogenation of (hetero)arenes. Catalysts based on precious metals, such as Ru and Rh, promote this reaction efficiently under mild reaction conditions. In contrast, heterogeneous catalysts based on earth‐abundant metals can selectively hydrogenate (hetero)arenes but require harsher reaction conditions. Bimetallic catalysts that combine precious and earth‐abundant metals are interesting materials to mitigate the drawbacks of each component. To this end, RuNi nanoparticles bearing a phosphine ligand were prepared through the decomposition of [Ru(η4‐C8H12)(η6‐C8H10)] and [Ni(η4‐C8H12)2] by H2 at 85 °C. Wide angle X‐ray scattering confirmed a bimetallic segregated structure, with Ni predominantly on the surface. Spectroscopic analyses revealed that the phosphine ligand coordinated to the surface of both metals, suggesting, as well, a partial Ni shell covering the Ru core. The RuNi‐based nanomaterials were used as catalysts in the hydrogenation of quinoline to assess the impact of the metallic composition and of the stabilizing agent on their catalytic performance. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) have experienced an explosive global growth as a key byproduct of nanotechnologies over the last ten years due to their remarkable physiochemical qualities. Bimetallic nanoparticles are a promising combination of two kinds of nanoparticles that often display synergetic behaviors. In the current study, a technology that is beneficial to the environment was used to biosynthesize copper oxide and gold nanoparticles (CuO@Au NPs) utilizing a fungus isolate. Using carboxymethylcellulose (CMC) and chitosan (Ch), formed nanoparticles were turned into biopolymers (nanocomposite) using a green method. CuO@Au NPs and nanocomposite qualities were investigated using physical and chemical methods including FITR and XRD, as well as topographical methods like FESEM and HRTEM. About 20 nm-diameter bimetallic NPs were identified in the nanocomposite, which was also determined to have verified nanostructures. CuO@Au NPs exhibited less antimicrobial activities with inhibition zones of 15, 27, 8, and 25 mm than nanocomposite with inhibition zones of 16, 26, 29, and 14 mm against E. coli, E. faecalis, C. albicans, A. flavus, and M. circinelloid respectively. CuO@Au NPs reflected more MIC value against S. aureus, (62.5 µg/mL), S. typhi (62.5 µg/mL), E. faecalis (31.25 µg/mL) than MIC value of nanocomposite against the same bacteria. Moreover, the MBC values of CuO@Au NPs were more (ranged from 31.25 to 125 µg/mL) than that of nanocomposite (ranged from 15.62 to 62.5 µg/mL) against tested bacteria. DPPH scavenging % indicated that nanocomposite was promising than CuO@Au NPs with IC50 value of 116.87 µg/mL and 173.34 µg/mL, respectively. Effect of CuO@Au NPs and nanocomposite on Wi38 reflected high IC50 of 585.15 ± 1.58 µg/mL and 587.14 ± 0.29 µg/mL, respectively against Wi38 cells. However, the recorded IC50 values of CuO@Au NPs were less (166.56 ± 2.91 µg/mL) than IC50 (181.8 ± 4.27 µg/mL) of the nanocomposite against MCF-7 cells. [ABSTRACT FROM AUTHOR]

Bimetallic nanoparticles (BNPs) have garnered a great interest rather than monometallic nanoparticles (NPs) in terms of biotechnological applications due to their enhanced properties. They have a growing interest as promising biomedical agents for drug delivery, antibacterial, and anticancer treatments due to their significant permeability and retention effects. Both of nano-size copper (Cu) and selenium (Se) exhibited a significant activity in biological treatment and drug delivery systems. Consequently, the present work aimed to focus on the novel biogenic synthesis of Cu-Se BNPs using cell-free extract of a marine bacterium, and studying their anticancer and antioxidant activities. Based on 16S rDNA sequencing, the isolated marine bacterium was identified Bacillus amyloliquefaciens by phylogenetic analysis. Biogenic synthesis of Cu-Se BNPs was optimized by studying the effect of some physiological factors such as reaction time, pH, and temperature. Based on the reaction conditions, the biologically synthesized Cu-Se NPs was obtained with different particle size that ranged from 15.7-106.0 nm. The spherical small sized (15.7 nm) bimetallic Cu-Se BNPs displayed anticancer activity against HepG2 and MDA cell lines, while the cell viability was reduced by 87 % and 81 %, respectively. The estimated IC50 values were 696.4 µg/ ml for HepG2 and 273.9 µg/ ml for MDA, while scavenging capacity (SC) of Cu-Se BNPs (SC50 = 305.3 µM) showed lower ability to 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) scavenging compared to ascorbic acid (SC50 = 95.9 µM).

The task of creating a remarkably stable and effective electrochemical catalyst for efficient hydrogen evolution is arduous, primarily due to the multitude of factors that need to be taken into account for the industrial utilization of Pt. In this work, hybrid formation through in - s i t u reduction of Pt onto biogenic porous silica (Pt-SiO 2) is tested for its use as an efficient catalyst for hydrogen production. Exceptionally high electrocatalytic activity and excellent reusability of catalysts up to 200 cycles have been demonstrated. Pt-SiO 2 with low Pt content of 0.48 to 0.82 at% with active catalytic sites exhibit superior catalytic activity with a Tafel slope of 22 mV dec−1 and an overpotential of 28 mV (vs. RHE at 10 mA cm−2) as compared to the Pt wire and previously reported bare Pt-SiO 2 (0.65 at% and 0.48 at% of Pt), and hybrid (Pt/Ag) structures formed onto two different biogenic porous SiO 2 substrates. The best catalytic performance of the Pt 1 Ag 3 cluster, representing a low Pt concentration, has been validated by Density Functional Theory (DFT) calculations. Here, the high production from the Pt 1 Ag 3 cluster is assigned to the mutual synergistic effect between Pt/Ag atoms. The Pt atoms transfer the excess charge to the nearest Ag neighbors inside the cluster, facilitating hydrogen diffusion on the activated sites. These important findings authenticate the superior hydrogen production at reduced Pt concentration on amine-functionalized biogenic porous silica.   [ABSTRACT FROM AUTHOR]

Abstract Biopolymers embedded with nanoparticles of metal oxides (MOs) demonstrate a wide range of bio-functions. Chitosan-incorporated MOs are an interesting class of support matrices for enhancing the biological function, compared to other support matrices. Therefore, the importance of this study lies in exploiting chitosan as a carrier not of one metal as in previous studies, but of two metals in the form of a nanocomposite to carry out several biological functions. The coprecipitation approach was employed to synthesize chitosan/Fe2O3/ZnO-nanocomposite in the present research. The characterization of chitosan/Fe2O3/ZnO-nanocomposite was performed to find out the morphology and dispersion properties of chitosan/Fe2O3/ZnO-nanocomposite. The X-ray diffraction (XRD) investigation revealed that these were crystalline. Fourier transforms infrared (FTIR) spectrum bands were viewed at 400/cm and 900/cm, due to the stretching vibration of Fe and Zn oxygen bond. TEM showed that chitosan/Fe2O3/ZnO-nanocomposite was of 20–95 nm in size. chitosan/Fe2O3/ZnO-nanocomposite exhibited inhibitory potential against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Candida albicans with inhibition zones of 25 ± 0.1, 28 ± 0.2, 27 ± 0.1, and 27 ± 0.2 mm, respectively while didn’t inhibited Aspergillus niger. MIC value of nanocomposite was 15.62 ± 0.33 µg/mL for C. albicans, B. subtilis and E. coli, while it was 62.50 ± 0.66 µg/mL for Pseudomonas aeruginosa. Ranged values of nanocomposite MBC (15.62 ± 0.33 to 125 ± 1 µg/mL) were attributed to all tested bacteria. Different concentrations of chitosan/Fe2O3/ZnO-nanocomposite MBC (25, 50, and 75%) reflected anti-biofilm activity against E. coli (85.0, 93.2, and 96.0%), B. subtilis (84.88, 92.21, and 96.99%), S. aureus 81.64, 90.52, and 94.64%) and P. aurogenosa (90.11, 94.43, and 98.24%), respectively. The differences in the levels of antimicrobial activities may depend on the type of examined microbes. Antioxidant activity of chitosan/Fe2O3/ZnO-nanocomposite was recorded with excellent IC50 values of 16.06 and 32.6 µg/mL using DPPH and ABTS scavenging, respectively. Wound heal by chitosan/Fe2O3/ZnO-nanocomposite was achieved with 100% compared to the untreated cells (76.75% of wound closer). The cytotoxicity outcomes showed that the IC50 of the chitosan/Fe2O3/ZnO-nanocomposite was 564.32 ± 1.46 µg/mL normal WI-38 cells. Based on the achieved findings, the chitosan/Fe2O3/ZnO-nanocomposite is a very promising agent for perform pharmacological activities.

The combination of iron and copper (Fe/Cu) loaded on glass (G-Fe/Cu) has been developed for this study. The green synthesis was used to create bimetallic nanoparticles (G-Fe/Cu) using grape leaves extract, which employed as a natural reducing agent to easily produce nZVI from iron salts. The particle size, surface morphology, elemental composition and degree of crystallinity of the resulting nanocomposite have been analyzed by means of energy-dispersive X-ray spectroscopy (EDX), scanning electronic microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), Energy dispersive X-ray spectroscopy (EDS), and transmission electron microscopy (TEM). G-Fe/Cu nanocomposite were employed as adsorbent materials to eliminate ciprofloxacin (CIP) from polluted aqueous solution. Some factors affecting the adsorption function, in batch and continuous experimentations have been examined to select the optimum parameters that accomplish the maximum elimination ratio (99 %) and to investigate the efficiency of the nanoparticles as reactive bed materials. It was discovered that the ideal conditions were CIP concentration (50 ppm), pH 7, nanoparticles dosage (0.5 mg/ 50 mL) and 100 min of optimum contact time. In present paper, the response surface methodology (RSM) was applied as statistical tool used to optimize and model complex systems for elimination of CIP antibiotic from aqueous solution with selection the same four factors that mentioned above. The best appropriate isotherm model was the Freundlich model in batch study. The findings imply that hazardous compounds can be successfully eliminated from aqueous solutions using the prepared nanocomposites. The model's predictions aligned well with experimental outcomes, and the G-Fe/Cu nanocomposite effectively removed CIP from the solutions.

Biopolymers embedded with nanoparticles of metal oxides (MOs) demonstrate a wide range of bio-functions. Chitosan-incorporated MOs are an interesting class of support matrices for enhancing the biological function, compared to other support matrices. Therefore, the importance of this study lies in exploiting chitosan as a carrier not of one metal as in previous studies, but of two metals in the form of a nanocomposite to carry out several biological functions. The coprecipitation approach was employed to synthesize chitosan/Fe2O3/ZnO-nanocomposite in the present research. The characterization of chitosan/Fe2O3/ZnO-nanocomposite was performed to find out the morphology and dispersion properties of chitosan/Fe2O3/ZnO-nanocomposite. The X-ray diffraction (XRD) investigation revealed that these were crystalline. Fourier transforms infrared (FTIR) spectrum bands were viewed at 400/cm and 900/cm, due to the stretching vibration of Fe and Zn oxygen bond. TEM showed that chitosan/Fe2O3/ZnO-nanocomposite was of 20–95 nm in size. chitosan/Fe2O3/ZnO-nanocomposite exhibited inhibitory potential against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Candida albicans with inhibition zones of 25 ± 0.1, 28 ± 0.2, 27 ± 0.1, and 27 ± 0.2 mm, respectively while didn't inhibited Aspergillus niger. MIC value of nanocomposite was 15.62 ± 0.33 µg/mL for C. albicans, B. subtilis and E. coli, while it was 62.50 ± 0.66 µg/mL for Pseudomonas aeruginosa. Ranged values of nanocomposite MBC (15.62 ± 0.33 to 125 ± 1 µg/mL) were attributed to all tested bacteria. Different concentrations of chitosan/Fe2O3/ZnO-nanocomposite MBC (25, 50, and 75%) reflected anti-biofilm activity against E. coli (85.0, 93.2, and 96.0%), B. subtilis (84.88, 92.21, and 96.99%), S. aureus 81.64, 90.52, and 94.64%) and P. aurogenosa (90.11, 94.43, and 98.24%), respectively. The differences in the levels of antimicrobial activities may depend on the type of examined microbes. Antioxidant activity of chitosan/Fe2O3/ZnO-nanocomposite was recorded with excellent IC50 values of 16.06 and 32.6 µg/mL using DPPH and ABTS scavenging, respectively. Wound heal by chitosan/Fe2O3/ZnO-nanocomposite was achieved with 100% compared to the untreated cells (76.75% of wound closer). The cytotoxicity outcomes showed that the IC50 of the chitosan/Fe2O3/ZnO-nanocomposite was 564.32 ± 1.46 µg/mL normal WI-38 cells. Based on the achieved findings, the chitosan/Fe2O3/ZnO-nanocomposite is a very promising agent for perform pharmacological activities. [ABSTRACT FROM AUTHOR]

Zeolite imidazolate frameworks (ZIFs) have recently attracted eminent attention in the field of photocatalytic hydrogen generation. Herein, we first report and demonstrate the π–π interactions among bimetallic ZnCd-ZIF-8 and GO and their probed catalytic activity over the photocatalytic hydrogen generation efficiency. The successful synthesis of bimetallic ZIFs (ZnCd-ZIF-8) with the confined loading of a porous nanospace on GO enhances photocatalytic efficiency. The synthesized GO/ZnCd-ZIF-8(10) exhibited exceptional photocatalytic hydrogen generation efficiency of 2.4 mmol g–1 h–1 and AQY of 1.56% in 4 h. The optical and photoelectrochemical studies of the photocatalysts demonstrate the proximity of the catalytic active centers of GO toward water splitting and the Zn-Cd metal centers, with their chemical binding and stabilization, with increased electron–hole separation efficiency and charge transfer over the nanopores. The real-time studies demonstrate that the strong π–π interactions between ZnCd-ZIF-8 and GO are highly efficient toward photoinduced charge separation, confirmed through the Nyquist plot, which demonstrates their easy electron transfer over the hybrid photocatalyst, further leading to effectively enhanced water splitting. [ABSTRACT FROM AUTHOR]

In this study, a bimetallic Co–Fe nanocatalyst supported on carbon quantum dots (CQDs) is introduced as an effective catalyst for promoting hydrogen generation upon hydrolysis of sodium borohydride. Hydrothermal synthesis routes were used to produce CQDs support. All samples were subjected to analysis using XRD, UV–Vis, Raman, FTIR, FESEM, EDX, and nitrogen adsorption-desorption techniques. Benefiting from the higher surface area (51 m 2 g r ), pore volume (0.200 m L g r ), and good dispersion of Co–Fe nanoparticles over the CQDs support, the CoFe/CQD spherical nanocatalysts with 5 wt.% iron content exhibited the highest catalytic activity of 20200 mL/min.g cat within only 1 min of reaction. The kinetics studies revealed a low activation energy of 48 kJ/mol over this optimum catalyst. In addition, it was found that the catalytic performance of this catalyst was decreased after 4 runs of recycling experiments. Catalyst degradation and leaching of the active phase were likely responsible for the decline in catalyst performance. [Display omitted] • Bimetallic Co–Fe nanocatalysts supported on carbon quantum dots CQDs were prepared. • The prepared catalysts were used for H 2 generation upon hydrolysis of NaBH 4. • CoFe/CQD with 5 wt% iron exhibited superior performance in the hydrolysis of NaBH 4. • CoFe/CQD with 5 wt% iron possessed a high hydrogen generation, 20200 mL/min.g cat. • The activation energy (E a) of this reaction was 49.5 kJ/mol over CoFe/CQD with 5 wt% iron. [ABSTRACT FROM AUTHOR]

Incorporating electrocatalytic active sites into the reticular framework allows for the design of novel catalytic structures promoting desired catalytic reactions with efficient mass transfer. However, to fully exploit the advantages of such a framework, it is crucial to ensure the electrochemical stability of the material. In this context, alkaline‐stable bimetallic MxNi2‐xCl2BTDD (M = Fe, Co) metal–organic frameworks (MOFs) are employed as electrocatalysts for alkaline water oxidation reaction (WOR) to understand the correlation between secondary metal incorporation and catalytic activity changes. For a specific Fe ratio within the MOF, the optimal catalytic activity is achieved at an overpotential of 315 mV at a WOR current density of 10 mA cm−2geo. Based on its well‐defined crystal structure and uniformly arranged metal nodes, which are not limited to specific facets, the cooperative electrocatalytic mechanism during the faradaic WOR process is investigated through operando Raman spectroscopy and density functional theory calculations. These results enable the interpretation of the electrochemical WOR mechanism based on MOF, providing a further fundamental understanding of electrocatalytic activity in bimetallic systems. [ABSTRACT FROM AUTHOR]

The inherent and unique charge‐carrier release characteristics of piezoelectric sonosensitizers with desired bandgap can be leveraged to initiate reactive oxygen species (ROS) reactions that have considerable potential for sonodynamic therapy (SDT). In this study, a bimetallic Bi4NbO8Br‐polyvinylpyrrolidone (BNOBP) with a small bandgap (2.45 eV) is synthesized as a potential piezoelectric sonosensitizer. The robust interactions within and between the Bi─O and Nb─O layers narrow the bandgap, facilitating carrier transfer. Concurrently, compared with that of TiO2 and BiOBr, BNOBP exhibits a rapid acoustoelectric response and desirable electron–hole separation efficiency, enabling the generation of ·O2− under ultrasound (US) irradiation. Notably, BNOBP alleviates the overexpression of glutathione (GSH) in tumors and prevents the consumption of the generated ROS by GSH. Combining the previous small bandgap endow the high ROS generation efficiency, this study provides a paradigm for in situ regulation of oxidative stress levels in tumor tissue microenvironment based on bimetallic piezoelectric sonosensitizers. [ABSTRACT FROM AUTHOR]

The novel flower shaped nanomaterials, known as Nanoflowers (NFs), have attracted the interest of the scientific community around the world with their unique morphology, ease of synthesis, large surface-to-volume ratio, and high electron conductivity, making them a promising nanomaterial for various relevant applications. Bimetallic NFs comprise of two different metallic elements, with superior properties due to the synergistic effect between the hereditary properties of the constituent metal atoms. Bimetallic NFs can be synthesized through various methods, each offering unique advantages. Conventional methods provide a traditional approach to NF synthesis, while electrodeposition methods offer precise control over NF morphology and composition. Biological methods harness the power of biological systems for green and sustainable NF synthesis. Various characterization techniques for identifying the morphology of NFs include HR-TEM, SEM, EDX, XRD etc. These NFs exhibit exemplary catalytic activity with high selectivity and catalytic yield due to their large surface areas and augmented active site density. This review delineates the synthesis, morphology, electronic properties and catalytic applications of bimetallic NFs. The manuscript depicts various catalytic reactions and focuses on mechanism and role of bimetallic NFs in these reactions. Moreover, the recent challenges and future prospects of these bimetallic NFs are well discussed in detail. [ABSTRACT FROM AUTHOR]

An innovative photonic crystal fiber (PCF) biosensor using surface plasmon resonance (SPR) to diagnose six distinct kinds of cancers (skin cancer, cervical cancer, adrenal gland cancer, blood cancer, and breast cancer types 1 and 2) in cells is demonstrated here and incorporates with two microchannels and a bimetallic configuration. The numerical analysis utilizes the finite element method (FEM) combined with perfectly matched layers (PML). The plasmonic material employed in the biosensor is gold (Au), and a supportive material, titanium dioxide (TiO2), is combined with Au. By combining these two materials, the sensor's performance is improved. The numerical calculations indicate that breast cancer type 2 has the highest wavelength sensitivity (24,285.71 nm/RIU) and amplitude sensitivity (3959 RIU−1). The rest of the cancer cells' wavelength sensitivities are 11,000.00 nm/RIU (skin cancer), 13,333.33 nm/RIU (cervical cancer), 15,000.00 nm/RIU (blood cancer), 17,142.85 nm/RIU (adrenal gland cancer), and 21,428.57 nm/RIU (breast cancer type 1). This advanced biosensor has several uses in biological sensing and medical technology, and it has the potential to revolutionize cancer identification and medical diagnosis. [ABSTRACT FROM AUTHOR]

Core/shell Fe@Au nanostructures with their unique physicochemical properties have been widely studied in a wide variety of biomedical programs, such as imaging, biosensing, hyperthermia, drug delivery, and tissue engineering. Core/shell hematite (α-Fe2O3)@Au nanotruffles were synthesized using Rosmarinus officinalis leaf extract as natural reducing agent. First, hematite (α-Fe2O3) nanoparticles were fabricated using phenolic compounds in rosemary extract. Then, the Au nanoparticles were coated on the α-Fe2O3 core nanoparticles without utilizing any intermediate material. The physicochemical properties of the Fe2O3@Au nanotruffles were evaluated by XRD, FTIR, FESEM-EDAX, HR-TEM, and XPS. Due to the specific morphology of Fe2O3@Au nanotruffles, the Au shell thickness varied from 2.3 to 9 nm in different regions. The toxicity of the core/shell α-Fe2O3@Au nanotruffles with different concentrations was evaluated on human glioblastoma U87 cancer and PC12 pheochromocytoma cells based on MTT assay. The results established that these nanotruffles had the high toxicity effect on glioblastoma cells at a concentration of 500 μg/mL. Additionally, their antibacterial was evaluated on Escherichia coli and Streptococcus mutans by using the dilution method. [ABSTRACT FROM AUTHOR]

Platinum-based bimetallic nanoparticles (NPs) are of great interest for their applications in catalysis. The catalytic properties of these NPs are significantly dependent on their morphology, structure, and composition, whose response to thermal input remains challenging to be fully understood. This study investigates the thermally induced structural and chemical evolutions of single-crystalline Pt–Ni NPs using in situ transmission electron microscopy. The observed morphological evolution includes the facet development from a truncated octahedron to a spherical-like isotropic shape, followed by the formation of a pancake-like ellipsoid shape at high temperatures due to surface atom migration and interfacial wetting enabled by the particle–substrate interaction. Comparative investigations by in situ scanning transmission electron microscopy with energy-dispersive X-ray spectroscopy mapping elucidate that the solid-solution compositional configuration can be retained over a large temperature range, while core–shell NPs undergo irreversible solid-solution transitions through chemical homogenization at elevated temperatures. These findings elucidate the effect of thermal input on the structural evolution and compositional redistribution of Pt–Ni bimetallic NPs, offering valuable insights into the design of heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

Although Ag is a stable enough metal to be used as the electrocatalyst in alkaline fuel cells for the oxygen reduction reaction (ORR), its activity is far less compared to that of the commercial Pt/C. We report here a tailored fabricated Ag-core–AuAg-sandwiched–Ag-shell [(Ag@AuAg)@Ag] nanoscale material for application as a catalyst of an efficient ORR (kinetically sluggish process in the absence of a catalyst) in fuel cells via a stepwise template-mediated process. In this work, we not only showcased the worsened behaviors of Au on the surface to hinder the ORR but also justified its benefits as the core of a nanoscale material to positively influence the facile charge transfer from surface Ag to core Au to follow a four-electron-transfer pathway for ORR by producing water as the main product. This facile electron mobility enhances the Ag oxophilicity and thereby enhances the ORR kinetics. On the contrary, when both Au and Ag are present on the surface, while the core is purely made of Ag, the charge transfer is still facile but the availability of a smaller number of active sites (Ag) reduces the rate of ORR. For materials made of pure Au on the surface, the reaction rate decreases further and proceeds via a two-electron-transfer process, producing hydrogen peroxide. The newly developed electrocatalyst [(Ag@AuAg)@Ag] shows ORR activity comparable to that of Pt/C, but with regard to stability, (Ag@AuAg)@Ag is much better, holding 97% of its current density after 7 h of chronoamperometric studies. [ABSTRACT FROM AUTHOR]

Bimetallic nanomaterials have generated significant interest across diverse scientific disciplines, due to their unique and tunable properties arising from the synergistic combination of two distinct metallic elements. This study presents a novel approach for synthesizing branched gold–platinum nanoparticles by utilizing poly(allylamine hydrochloride) (PAH)-stabilized branched gold nanoparticles, with a localized surface plasmon resonance (LSPR) response of around 1000 nm, as a template for platinum deposition. This approach allows precise control over nanoparticle size, the LSPR band, and the branching degree at an ambient temperature, without the need for high temperatures or organic solvents. The resulting AuPt branched nanoparticles not only demonstrate optical activity but also enhanced catalytic properties. To evaluate their catalytic potential, we compared the enzymatic capabilities of gold and gold–platinum nanoparticles by examining their peroxidase-like activity in the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB). Our findings revealed that the incorporation of platinum onto the gold surface substantially enhanced the catalytic efficiency, highlighting the potential of these bimetallic nanoparticles in catalytic applications. [ABSTRACT FROM AUTHOR]

M-iridium (M = cobalt (Co), nickel (Ni)) bimetallic alloy catalysts with low iridium (Ir) loading of 0.3–2.0 mg·cm−2 were prepared on copper foam (CF) supports by electrodeposition. The top surface of as-deposited M-Ir catalysts was mainly composed of metallic state and oxides states, such as metallic Ir, Ni(OH)2 or Co(OH)2, Co(Ir) and Ni(Ir) solid solution, Ir oxides. M-Ir catalysts with low Ir loading exhibited excellent catalytic performance. Ni63.4Ir36.6/CF catalyst with low Ir loading of 1.8 mg·cm−2 achieved a current density of 10 mA·cm2 at an overpotential of 52 mV and a Tafel slope of 36 mV·dec−1. Co64.2Ir35.8/CF catalyst with low Ir loading of 0.7 mg·cm−2 was uniformly scattered with small ellipsoidal particles, looking like fine fluff, requiring an overpotential of 51 mV for hydrogen evolution reaction to reach a current density of 10 mA·cm−2, having a Tafel slope of 38 mV·dec−1. After long-term hydrogen evolution testing, M-Ir/CF catalysts exhibited excellent electrocatalytic stability for water splitting in alkaline solution. [ABSTRACT FROM AUTHOR]

The ability to economically offer distinct properties within a single component has gathered significant attention for bimetallic or cladded tubular components across various industries. A novel friction stir-based cladding method and its in-depth analyses to achieve internal cladding of Al inside the stainless steel (SS) tubes are presented. The process outcome with the variation in process parameters and its impact on heat generation and intermetallic compounds (IMCs) formation was analyzed. In this process, the joining between the base substrate and the cladded material is due to the heat generation that leads to interdiffusion and ultimately promotes the formation of IMCs. The mechanism of IMCs formation, its growth phenomenon, and its impact on joining efficacy were investigated. The cladded Al exhibited an approximately twofold increase in grain size compared to the base Al alloy, as revealed through electron back-scattered diffraction (EBSD) analysis. The coarser grains help to restrict the propagation of fracture during the flattening test. The cladded tube exhibits no sign of delamination after compression, which paves the way for the industrial adoption of the process. [Display omitted] • Friction stir backward extrusion based bimetallic tubular component fabrication. • Analysis of heat generation and its impact on the formation of IMCs. • Confirmation of Al-rich IMCs at the interface and its effects on bonding. • Uniform IMC layer thickness (3-4 µm) results in optimum bond strength at interface. • A twofold increase in the grain size of Al, resulting in resistance to delamination. [ABSTRACT FROM AUTHOR]

Bimetallic nanoparticles (BMNPs) have gained considerable attention due to their remarkable catalytic properties, making them invaluable in wastewater treatment applications. One of these challenges lies in the propensity of BMNPs to aggregate due to Van der Waals interactions, which can reduce their overall performance. Additionally, retrieving exhausted NPs from the treated solution for subsequent reuse remains a significant hurdle. Moreover, the leaching of NPs into the discharged wastewater can have harmful effects on humans as well as aquatic life. To overcome these issues, various substrates have been researched to maximize the efficiency and stability of the NPs. This review paper delves into the pivotal role of various substrates in immobilizing BMNPs, providing a comprehensive analysis of their performances, advantages, and drawbacks. The substrates encompass a diverse range of materials, including organic, inorganic, organic-inorganic, beads, fibers, and membranes. Each substrate type offers unique attributes, influencing the stability, efficiency, and recyclability of BMNPs. This review paper aims to provide an up-to-date and detailed analysis and comparison of the substrates used for the immobilization of BMNPs. This work further reviews the underlying mechanisms of the composites involved in treating pollutants from wastewater and how these mechanisms are enhanced by the synergistic effects produced by the substrate and BMNPs. Furthermore, the reusability and sustainability of these composites are discussed. Also, high-performing substrates are highlighted to give direction to future research focusing on the immobilization of BMNPs in the application of wastewater treatment. [ABSTRACT FROM AUTHOR]

Electrode modification has been one of the most active areas of interest in electrochemistry research. Hence, the investigation of the effects of chemically and electrochemically modified GCE nano-films on the NPs electrochemical properties. The electrochemistry of nano-films of Ag NPs, Au NPs and bimetallic Ag-Au (1:2) NPs of chemical citrate reduction synthesis drop coated (DCT) and electro-deposition method (EDP) are reported. The Chemically synthesized NPs were confirmed through FT-IR, UV–visible, XRD and SEM techniques while electro-deposited NPs were ascertained by double-pulsed chrono-amperometry and electrochemical impedance spectroscopy (EIS). The nano films; GCE/Ag NPs, GCE/Au NPs and GCE/Ag-Ag (1:2) NPs in 0.1 M HCl supporting electrolyte were studied via Cyclic Voltammetry (CV) and Differential Pulse Voltammetry (DPV) techniques. Generally the DCT nano films were electrochemically superior to the EDP film in terms of current intensities and GCE/Ag-Au (1:2) NPs showed enhanced α (0.019), ks (0.01 s−1), Q (3.6 × 10−9 C), Γ (5.3 × 10−13molescm−2) and D (1.31 × 10−1 cm2s−1), indicating better physicochemical properties for possible sensing applications compared to electro-deposited GCE nano-films.

Abstract Herein, core–shell magnetic nanoparticles are modified with imidazolium-tagged phosphine and propylene glycol moieties and used for the stabilization of bimetallic AuCu nanoparticles. The structure and morphology of the prepared material are identified with SEM, TEM, XRD, XPS, atomic absorption spectroscopy, Fourier translation infrared spectroscopy, and a vibrating sample magnetometer. This hydrophilic magnetic bimetallic catalyst is applied in the reduction of toxic nitroarenes and reductive degradation of hazardous organic dyes such as methyl orange (MO), methyl red (MR), and rhodamine B (RhB), as well as in the degradation of tetracycline (TC). This magnetic AuCu catalyst indicated superior activity in all three mentioned reactions in comparison with its single metal Au and Cu analogs. This catalyst is recycled for 17 consecutive runs in the reduction of 4-nitrophenol to 4-aminophenol without a significant decrease in catalytic activity and recycled catalyst is characterized.

This study presents the development of an affordable and straightforward solution-based surface-enhanced Raman scattering (SERS) detection platform, employing plasmonic-active silver–gold nanostars coated with graphene oxide (GO-SGNS). The inclusion of GO with SGNS produced several advantages, including colloidal stability, SERS detection reproducibility, and improved sensitivity. The solution-based SERS platform exhibited an ultralow detection capability with high reproducibility, and we achieved the limit of detection (LOD) as low as 10, 50, 100, and 100 pM for the pesticides-ziram, phorate, triazophos, and azinphos-methyl, respectively. To illustrate the potential for food safety, the surfaces of apples were pretreated with pesticides and were directly analyzed without any sample pretreatment. Furthermore, the solution-based SERS platform provided rapid detection of the four pesticides in binary and quaternary mixtures on apple surfaces, indicating good feasibility and multiplex capability of the method. [ABSTRACT FROM AUTHOR]

The homogeneously catalyzed Guerbet upgrading of ethanol to butanol can be modulated by the application of partial H2 pressure before the reaction. Ruthenium(II) PNP pincer complexes with methylene‐extended acridine‐based ligands and singly‐chelated ruthenium(II) complexes with PN ligands perform best at very low catalyst loadings and upon the application of catalyst‐specific pre‐reaction partial H2 pressure. The combination of ruthenium(II) PNP pincer complexes and manganese(I) pincer complexes with MACHO‐type PNP ligands allows for even lower ruthenium loadings while retaining low base load and consumption, thus enabling high space‐time yields, catalyst productivity and recyclability. Mechanistically, Mn is proposed to stabilize coordinatively unsaturated Ru species and allow coordination of ethoxide to Ru instead of attacking the electrophilic ligand backbone based on NMR spectroscopy and X‐ray crystallography. [ABSTRACT FROM AUTHOR]

[Display omitted] • Facile synthesis of anode material with organized structure. • Binary composite demonstrates better performance than its unitary counterpart. • In-situ XRD together with in-depth characterization reveals sodium ion storage. • DFT calculation verifies the sodium migration barrier. Sodium-ion batteries offer significant advantages in terms of low-temperature performance and safety. In this study, we present a straightforward synthetic approach to produce bimetallic selenide NiCoSe 2 nanoparticles grown on a three-dimensional porous carbon framework for application as anode materials in sodium-ion batteries. This unique architecture enhances reaction kinetics and structural stability. The three-dimensional interconnected porous carbon network establishes a continuous pathway of electronic conductive, while increasing specific surface area and mitigating volume expansion. Consequently, these features expedite ion transfer and enhance electrolyte interaction. Notably, compared to CoSe, NiCoSe 2 exhibits reduced ion transport distances and lower sodium diffusion barriers. Leveraging these attributes, NiCoSe 2 /N, Se co-doped carbon composite materials (NiCoSe 2 /NSC) demonstrate a high specific capacity of 320.8 mAh/g, even after 1000 cycles at 5.0 A/g, with a capacity retention rate of 85.1%. The study further delves into the revelation of the reaction mechanism and ion transport pathway through in-situ X-ray diffraction (XRD) analysis and theoretical calculations. The development of these anode materials is poised to pave the way for advancements in sodium-ion battery technology. [ABSTRACT FROM AUTHOR]

The phytofabrication of selenium-silver bimetallic nanoparticles (Se-Ag BNPs) utilizing Echinacea purpurea aqueous extract is investigated in this study. The synthesis process is characterized by a visible color change to dark reddish brown, a sign indicating successful nanoparticle formation. UV-visible spectrum analysis confirms the presence of SeNPs and AgNPs with absorption maxima at 268 nm and 325 nm, respectively. X-ray diffraction (XRD) patterns reveal the crystalline structure of the synthesized Se-Ag BNPs, exhibiting characteristic peaks consistent with metallic silver and selenium nanoparticles. Transmission electron microscopy (TEM) analysis showcases the diverse morphological structures of the Se-Ag BNPs, predominantly spherical but also featuring hexagonal and oval shapes. The average particle size is determined to be 33.38 nm, indicating uniformity and stability. Furthermore, the antioxidant properties of Se-Ag BNPs are evaluated through DPPH and ABTS radical scavenging assays, demonstrating dose-dependent scavenging capabilities with IC50 values of 264.78 µg/mL and 344.19 µg/mL, respectively. These findings underscore the potential of Se-Ag BNPs as effective antioxidants, offering promising applications in various fields such as biomedicine and environmental remediation. Comparisons with previous studies highlight the efficacy of the biosynthesis method using Echinacea purpurea extract in producing Se-Ag BNPs with superior antioxidant activity. [ABSTRACT FROM AUTHOR]

Introduction: The emergence of multi-drug-resistant bacteria is one of the main concerns in the health sector worldwide. The conventional strategies for treatment and prophylaxis against microbial infections include the use of antibiotics. However, these drugs are failing due to the increasing antimicrobial resistance. The unavailability of effective antibiotics highlights the need to discover effective alternatives to combat bacterial infections. One option is the use of metallic nanoparticles, which are toxic to some microorganisms due to their nanometric size. Methods: In this study we (1) synthesize and characterize bismuth and silver nanoparticles, (2) evaluate the antibacterial activity of NPs against Staphylococcus aureus and Escherichia coli in several infection models (in vivo models: infected wound and sepsis and in vitro model: mastitis), and we (3) determine the cytotoxic effect on several cell lines representative of the skin tissue. Results and discussion: We obtained bimetallic nanoparticles of bismuth and silver in a stable aqueous solution from a single reaction by chemical synthesis. These nanoparticles show antibacterial activity on S. aureus and E. coli in vitro without cytotoxic effects on fibroblast, endothelial vascular, and mammary epithelium cell lines. In an infected-wound mice model, antibacterial effect was observed, without effect on in vitro mastitis and sepsis models. [ABSTRACT FROM AUTHOR]

For the first time, a bimetallic metal–organic framework of (MOF) La3+ and Ce3+ (Ce, La-MOF) was synthesized using a new solvothermal route. Also, monometallic MOFs La3+ (La-MOF) and Ce3+ (Ce-MOF) were synthesized using the mentioned method. To identify, and analyze the synthesized nanostructures, field emission scanning microscopy (FSEM), energy dispersive X-ray mapping (MAP), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), thermal gravity curve (TGA), differential scanning calorimetry (DSC) analysis, Fourier transforms infrared (FT-IR) spectroscopy and Brunauer–Emmt–Teller surface area (BET) were used. According to the XRD diffraction patterns of Ce–La-MOF nanostructure, no additional peaks are derived from La species, which confirms that the addition of La does not change the crystalline phase structure of Ce-MOF. The size of La-MOF, Ce-MOF, and Ce, La-MOF nanostructures was calculated by the Williamson-Hall method and reported as 72.97, 55.46, and 81.55 nm, respectively. The specific surface area (BET) results for La-MOF, Ce-MOF, and Ce, La-MOF nanostructures were reported as 140, 200, and 260 m2 g−1 respectively, and the mean pore volumes of the nanostructures were reported as 0.019, 0.022 and 0.030 cm3 respectively. These values allow the use of these versatile nanostructures in various applications such as biosensing, separation and purification, medicine field, and catalysts. In addition, in this study, modified electrodes for synthesized nanostructures were tested for the electrooxidation of acetaminophen. And the obtained results show better electrocatalytic behavior of bimetallic Ce, La-MOF nanostructures than monometallic La-MOF, Ce-MOF nanostructures against acetaminophen. [ABSTRACT FROM AUTHOR]

Investigating the impact of successive introduction of precursor in making of silver-copper bimetallic green nanoparticles utilizing Tulsi leaf extract both as a stabilizing and reducing agent. Green synthesis methods using plants and plant-based extract are more beneficial and biodegradable than any other synthesis methods. Compared to other approaches plants generate nanoparticles which are more stable, and scaling them up is very easy. The impact of electronegativity of Ag and Cu metals on the formation and growth of these bimetallic nanoparticles has been studied. Energy Dispersive X-ray analysis (EDX) and scanning electron microscopy (SEM) were used to investigate the biosynthesized Ag-Cu nanoparticles and Cu-Ag nanoparticles. [ABSTRACT FROM AUTHOR]

This paper reports on the optimization of fenitrothion photocatalytic degradation in visible light based on Plackett Burman (PB) design and central composite design (CCD) in response surface methodology (RSM). A herbicide routinely used with a negative impact on the environment is fenitrothion, which must be degraded to minimize the impact on the environment. For fenitrothion degradation, Ag-Au bimetallic nanoparticles on the semiconducting s-doped gC3N4 surface were synthesized using the galvanic exchange. The properties of s-gC3N4/Ag-Au bimetallic nanocomposite were confirmed by various methods. Significant factors responsible for fenitrothion photocatalytic degradation were determined using Plackett-Burman (PB) design and were catalyst dosage, initial fenitrothion concentration, H2O2 concentration, pH, and rotational speed. Central composite design (CCD) design was used for further optimization. The optimum conditions for the maximum degradation of fenitrothion (100%) constraints were found to be 100% an amount of H2O2 concentration 60 mM, pH 10, rotational speed 700 rpm. These results showed that s-gC3N4/Ag-Au bimetallic nanocomposite could act as a suitable photocatalyst under visible light in the degradation of fenitrothion. By removing fenitrothion from real water samples, as well as by maintaining its stability and reusability in five successive cycles, the practicality of this nanocomposite was demonstrated. [ABSTRACT FROM AUTHOR]

Herein, core–shell magnetic nanoparticles are modified with imidazolium-tagged phosphine and propylene glycol moieties and used for the stabilization of bimetallic AuCu nanoparticles. The structure and morphology of the prepared material are identified with SEM, TEM, XRD, XPS, atomic absorption spectroscopy, Fourier translation infrared spectroscopy, and a vibrating sample magnetometer. This hydrophilic magnetic bimetallic catalyst is applied in the reduction of toxic nitroarenes and reductive degradation of hazardous organic dyes such as methyl orange (MO), methyl red (MR), and rhodamine B (RhB), as well as in the degradation of tetracycline (TC). This magnetic AuCu catalyst indicated superior activity in all three mentioned reactions in comparison with its single metal Au and Cu analogs. This catalyst is recycled for 17 consecutive runs in the reduction of 4-nitrophenol to 4-aminophenol without a significant decrease in catalytic activity and recycled catalyst is characterized. [ABSTRACT FROM AUTHOR]

A new sensor based on copper-zinc bimetal embedded and nitrogen-doped carbon-based composites (CuZn@NC) was prepared for triclosan (TCS) detection by pyrolyzing the precursor of Cu–Zn binuclear metal–organic framework (MOF). The performance for detecting TCS was evaluated using linear scanning voltammetry (LSV) and differential pulse voltammetry (DPV), and the proton and electron numbers during TCS oxidation have been proved to be one-to-one. The results indicated that CuZn@NC can present a satisfactory analysis performance for TCS detection. Under the optimized conditions, the linear response range was 0.2–600 µM and the detection limit was 47.9 nM. The sensor presented good stability (signal current dropped only 2.5% after 21 days) and good anti-interference of inorganic salts and small molecular organic acids. The good recovery (97.5–104.1%) for detecting spiked TCS in commercial products (toothpaste and hand sanitizer) suggested its potential for routine determination of TCS in real samples. [ABSTRACT FROM AUTHOR]

Bimetallic coordination polymers (CPs) have two different metal ions as connecting nodes in their polymer structure. The synthesis methods of bimetallic CPs are mainly categorized into the one-pot method and post-synthesis modifications according to various needs. Compared with monometallic CPs, bimetallic CPs have synergistic effects and excellent properties, such as higher gas adsorption rate, more efficient catalytic properties, stronger luminescent properties, and more stable loading platforms, which have been widely applied in the fields of gas adsorption, catalysis, energy storage as well as conversion, and biosensing. In recent years, the study of bimetallic CPs synergized with cancer drugs and functional nanomaterials for the therapy of cancer has increasingly attracted the attention of scientists. This review presents the research progress of bimetallic CPs in biosensing and biomedicine in the last five years and provides a perspective for their future development. [ABSTRACT FROM AUTHOR]

Utilizing plant extracts in the green synthesis of bimetallic nanoalloys receives more attention due to its eco-friendly, cheap, single-step, easy-handling method, producing highly active and biocompatible nanoalloys. Therefore, the aqueous extract of ginger rhizome was used to form bimetallic gold/silver (Au/Ag) nanoalloys. There were 37.3 mg.g−1 of total soluble carbs, 0.75 mg.g−1 of proteins, and 0.03 mg.g−1 of phenolic compounds quantified in ginger rhizome. The production of BAu/Ag-NPs relies on these components. The as-formed BAu/Ag-NPs were characterized using UV–Vis spectroscopy. The results showed that the peak surface plasmon resonance (SPR) occurred between 440 and 545 nm. The existence of several functional groups involved in the reduction and stability of the generated nanoalloys was shown by Fourier-transform infrared (FT-IR). The nanoalloys, with an average size of 49.1 ± 16.2 nm, were observed to be spherical using transmission electron microscopy (TEM). Energy-dispersive X-ray (EDX) indicated that the synthesized nanoalloy mainly consisted of Au and Ag ions, which made up (31.2 % and 47.1 %) and (45.9 % and 28.6 %) of the sample’s atomic and weight percentages, respectively. The crystallography of the nanoalloys was confirmed using XRD analysis. When examined for their capacity to suppress viral replication, the synthesized nanoalloys showed remarkable results, with 78.2 % inhibition against HAV and 69.6 % against Cox-B4. In addition, the anticancer activity of nanoalloys against oral epithelial cells (OEC), MCF7 adenocarcinoma cells, and HepG2 hepatocarcinoma cells was investigated using the MTT assay method. While the nanoalloys exhibited moderate toxicity towards normal OEC (IC50: 502.5 ± 2.8 g.mL−1), they showed substantial cytotoxicity towards cancer cells, MCF7 and HepG2, with IC50 values of 212.6 ± 4.4 and 117.9 ± 6.6 µg.mL−1, respectively. According to these data, BAu/Ag nanoalloys show potential as antiviral and anticancer drugs that selectively kill cancer cells.

In this study, six bimetallic rare earth (RE = La, Ce, Pr, Nd, Sm, Eu) cobalt nitrogen doped carbon nanotubes (RECo-NCNTs) were synthesized with g-C3N4 derivative method. These RECo-NCNTs were characterized by SEM, BET, XPS, XRD and Raman. In addition, their catalytic performances for oxygen reduction reaction (ORR) had also been tested. The introduction of rare earths did not destroy the structure of nanotubes but apparently change their ORR performances. The PrCo-NCNTs showed the significant improvement in catalytic ability for ORR (onset potential of 0.95 V and half-wave potential of 0.79 V), which is very close to that of commercial 20 % Pt/C. Moreover, PrCo-NCNTs exhibits an excellent catalytic stability (no activity decay after 10000st cycles) and an outstanding methanol toxic tolerance. Assembled in metal–air batteries (Zn-air, Al-air and Mg-air), the PrCo-NCNTs electrode also presents high power densities and discharge voltages.

The one-pot chemical reduction process was used to generate the bimetallic Ni–Mo nanoparticles attached to reduced graphene oxide (rGO) nanocomposite, which was then used as an effective counter electrode in dye-sensitized solar cells (DSSC). Diffraction patterns were used to investigate the face-centered crystalline structure of the spherical-shaped Ni–Mo nanoparticles that were uniformly anchored over the surface of rGO. The nanoparticles had an average diameter ranging from 70 to 120 nm. Raman spectroscopy was utilized to investigate the structural interaction that was created by the presence of bimetallic nanoparticles and the graphene oxide support. In addition, the rGO/Ni–Mo counter electrode equipped DSSC demonstrated the highest solar to electrical energy conversion efficiency of 3.11% under irradiation from one sun with a fill factor (FF) of 0.48.

The efficient synthesis of nanosheets containing two metal ions is currently a formidable challenge. Here, we attempted to dope lanthanide-based bimetals into porphyrin-based metal-organic skeleton materials (MOFs) by microwave-assisted heating. The results of the EDX, ICP, and XPS tests show that we have successfully synthesized porphyrin-based lanthanide bimetallic nanosheets (Tb-Eu-TCPP) using a household microwave oven. In addition, it is tested and experimentally evident that these nanosheets have a thinner thickness, a larger BET surface area, and higher photogenerated carrier separation efficiency than bulk porphyrin-based bimetallic materials, thus exhibiting enhanced photocatalytic activity and n-type semiconductor properties. Furthermore, the prepared Tb-Eu-TCPP nanomaterials are more efficient in generating single-linear state oxygen under visible light irradiation compared to pristine monometallic nanosheets due to the generation of bimetallic nodes. The significant increase in catalytic activity is attributed to the improved separation and transfer efficiency of photogenerated carriers. This study not only deepens our understanding of lanthanide bimetallic nanosheet materials but also introduces an innovative approach to improve the photocatalytic performance of MOFs. [ABSTRACT FROM AUTHOR]