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The study of bimetallic catalysts has scientific and technologic importance because of special catalytic activity towards several reactions. RhCu is an interesting bimetallic system due to combination of the very different catalytic activities of Rh and Cu. The catalytic activity of this bimetallic does not result from simple interpolation of the constituents. In fact, at low Cu content, the catalytic activity of RhCu is superior to that of Rh but when the Cu content is higher the activity decays. This is a curious trend which theoretical works had attempted to explain. This paper reports an overview of the most recent research works about this bimetallic system with emphasis in its especial characteristics.

Bimetallic structure of nanoparticles is of great interest due to their extraordinary properties, especially in combining the specialty of the core and its shell. This work reports the effect of pH on the synthesis of Ni–Au (nickel–gold) bimetallic nanoparticles. The synthesis involves a two-step process where Ni nanoparticles were first synthesized using polyol method with hydrazine as the reducing agent. This was followed by the process of reducing to Au in the solution containing pre-prepared Ni to form Ni–Au bimetallic nanoparticles using sodium citrate as the reducing agent. The results obtained from Transmission Electron Microscopy (TEM) show that the process can possibly produce either core-shell structure, or mixture of Ni and Au nanoparticles. Magnetic property of core-shell structure investigated using Vibrating Sample Magnetometer (VSM) demonstrated typical characteristic of ferromagnetic with an increased magnetization as compared to Ni nanoparticles. The saturation magnetization (M_s) and coercivity (H_c) were obtained as 19.1 emu/g and 222.3 Oe, respectively.

This paper deals with Density Functions Theory (DFT) based theoretical investigation of the dissociation of strong N–N triple bond of dinitrogen (N₂). Mono-metallic and bimetallic dimers of selected transition metals (Zr, Nb, Hf, and Ta) are used as adsorbent. The dissociation of N–N bond is found to be strongly dependent on orientation of N–N axis with respect to the axis of the adsorbent dimer. N–N axis perpendicular to dimer axis has been found to be suitable for dissociative adsorption of dinitrogen. Apart from orientation the combination of two different transition metal atoms in the dimer also has significant effect in the elongation and dissociation of N–N bond. Our study shows even 2-atom clusters (dimers) of these transition metals are capable of breaking N–N triple bond.

Bimetallic nanostructure of noble metals is an alternative material that can provide the tenability of plasmonic performance. In this study, the plasmonic silver–titanium nanoisland (Ag–Ti NI) films deposited on a silicon wafer and glass slide substrates were prepared by magnetron co-sputtering of high-purity Ag target (99.99%) operated at 100 W-DC source, and Ti target (99.99%) operated at 50–250 W-DC pulsed source. The surface morphologies of the prepared films revealed a noncontinuous island Ag–Ti according to the formation of thin film growth based on the Volmer–Weber model. An increase in the sputtering power of the Ti target caused an evident increase in the Ag–Ti NIs diameter. The localized surface plasmon resonance (LSPR) was evaluated by UV–Vis–NIR spectrophotometry. The LSPR peak shift disappears with an increase of the sputtering power of the Ti target.In addition, the results confirmed that the surface-enhanced Raman scattering (SERS) activity of the bimetallic Ag–Ti NIs significantly improved in performance and stability, which is promising for the application in analytical chemistry.

Synthesis, characterization and oxygen reduction reaction (ORR) catalytic properties of bimetallic sulfides CoS/MnS/N-C catalyst was discussed. The catalyst was derived from a typical Co based zeolitic imidazolate framework (ZIF-67) and manganese aminoporphyrin. 5,15-Bis(4-aminophenyl)-10,20-bis(4-bromophenyl) porphyrin manganese oxoacetate loaded with ZIF-67 forms a porphyrin loaded ZIF-67. This product was then calcined at 800ˆ∘C and vulcanized with thioacetamide to obtain the bimetallic sulfide product CoS/MnS/N-C. The structure of CoS/MnS/N-C was further characterized by XRD, XPS, FESEM and HRTEM spectra which indicated a novel porous and hollow sphere structure. The electrocatalytic properties of the bimetallic material as well as its parent porphyrin and ZIF-67 were also compared in alkaline condition (0.1 M KOH) with a rotating disk electrode. The prepared catalyst CoS/MnS/N-C exhibits a higher catalytic performance than its precursors (PorMnOAc, ZIF-67 and PorMnOAc loaded ZIF-67) with almost four electron transfers under this condition.

Over the past decade, functionalization with bimetallic catalysts have been studied owing to their excellent catalytic activities for various reactions, whereas few studies have been performed on cofunctionalization with two different types of metal catalysts despite its simplicity. This study examined the sensing performances of Nb₂O₅ nanorods cofunctionalized with Pd and Au nanoparticles. Pd, Au-cofunctionalized Nb₂O₅ nanorods were prepared by a hydrothermal technique. The Nb₂O₅ nanorods cofunctionalized with Pd and Au nanoparticles showed far stronger response to ethanol gas than the Pd or Au-functionalized counterpart. The origin for the enhanced response of the Pd, Au-cofunctionalized Nb₂O₅ nanorods is discussed.

Development of low-cost, highly active catalyst for efficient oxygen evolution reaction based on earth-abundant metals is still a great challenge. Here, we report that a rod-like bimetallic NiFe metal-organic framework (NiFe-MOF) can directly act as a highly efficient oxygen evolution reaction (OER) catalyst synthesized by a convenient-to-operate hydrothermal method. The rod-like NiFe-MOF can derive 10mAcm${}^{-2}$ with a low overpotential of only 26mV, and its Tafel slope is 40.82mVdec${}^{-1}$, which is superior to that of monometallic Ni-MOF or Fe-MOF, and even can be comparable to that of RuO₂. To identify the origin of enhancing OER activity, we resorted to X-ray diffraction, scanning electron microscope, transmission electron microscope, high resolution transmission electron microscopy image and nitrogen adsorption–desorption techniques and various electrochemical techniques to probe it gingerly. The results indicate that its high electrochemically active area and the synergistic effect of bimetallic node could be responsible for the surprisingly high catalytic performance of the NiFe-MOF. These results suggest that this kind of bimetallic MOF (NiFe-MOF) could be a promising electrocatalyst for oxygen evolution reaction.

Branched metal nanoparticles present a promising new class of materials, which have great potential as sensors, catalysts, drug carriers, and imaging agents, owing to their unique nanostructures, physicochemical properties, optical properties, and other characteristics. Many efforts have recently been devoted to the wet-chemical synthesis of branched metal nanoparticles. Seed-mediated growth and seedless growth are two main routes for producing branched metal nanoparticles. Most particle synthesis methods can be modified for different metal systems. In this review, various synthesis methods for the fabrication of branched monometallic, bimetallic, and multimetallic nanoparticles and also branched polymer core-metal nanoshell composite nanoparticles are summarized, catagorized, and discussed. The relevance and performance of such nanostructured materials with regard to their optical properties which arise from localized surface plasmon resonances are summarized, and their potential as excellent substrates for surface enhanced Raman scattering (SERS) is reviewed. Other applications of branched nanoparticles such as drug delivery vehicle, medical imaging agent, catalysis, and magnetism are briefly introduced.

Each type of hammer currently being used in hammer crushers has its own individual disadvantages. High manganese steel hammers present wear problems, high chromium cast iron hammers are fragile, and general composite hammers are plagued by the “eat handle” phenomenon. As such, an application study was conducted on composite materials and production processes. By using a bimetallic composite casting hammer, different materials can be used for each role such that the advantages of each metal are fully utilized. The handle and end of the hammer adopt the distinct characteristics of its component low alloy steel and high chromium cast iron respectively, thereby improving the original double-metal composite technology. With the improved casting process, the interface location has changed. Thus, while some additional difficulties are involved in the production process, it should be ensured that a completely metallurgical bond is formed during actual implementation.

The study of bimetallic catalysts has scientific and technologic importance because of special catalytic activity towards several reactions. RhCu is an interesting bimetallic system due to combination of the very different catalytic activities of Rh and Cu. The catalytic activity of this bimetallic does not result from simple interpolation of the constituents. In fact, at low Cu content, the catalytic activity of RhCu is superior to that of Rh but when the Cu content is higher the activity decays. This is a curious trend which theoretical works had attempted to explain. This paper reports an overview of the most recent research works about this bimetallic system with emphasis in its especial characteristics.