One-Step and Morphology-Controlled Synthesis of Ni-Co Binary Hydroxide on Nickel Foam for High-Performance Supercapacitors

Ni-Co binary hydroxide grown on nickel foam was synthesized through a facile one-step process for pseudocapacitive electrode application. The morphology of the fabricated binary hydroxide, evolving from nanosheet to nanowire, was highly controllable by tuning the Ni:Co ratio. In systematical electrochemical measurements, the prepared binary material on nickel foam could be employed as a binder-free working electrode directly. The optimal composition obtained at the Ni:Co ratio of 5:5 in integrated nanosheet/nanowire geometry exhibited high specific capacitances of 2807 and 2222 F/g at current densities of 1 and 20 A/g, equivalent to excellent rate capability. The capacitance loss was 19.8% after 2000 cycles, demonstrating good long-term cyclic stability. The outstanding supercapacitors behaviors benefited from unique structure and synergistic contributions, indicating the great potential of the obtained binary hydroxide electrode for high-performance energy storage devices.

Selective capturing of phenolic derivative by a binary metal oxide microcubes for its detection

Development of highly efficient and potential material for toxic p-nitrophenol is an important design for sensitive detection of hazardous species from ecology and environment. Here it is developed, an efficient as well as selective of p-nitrophenol using binary material by electrochemical performances, including good linearity, lower detection limit, good stability, higher reproducibility and extreme sensitivity. The prepared electrode was fabricated by immobilization of SnO2/CdO microcubes (MCs) with conducting coating binders by using well-known glassy carbon electrode (GCE). The proposed MCs with SnO2/CdO were well-functionalized and prepared by facile hydrothermal technique. The general instrumentation namely, FTIR, UV/vis, FESEM, XPS, TEM, EDS, and powder XRD were employed for the morphological evaluation of the prepared doped MCs, structural, optical and elemental analyses. The large dynamic range (LDR) from 1.0 to 0.01 mM with 0.13 pM detection limit (S/N = 3), limit of quantification (LOQ; 0.43 pM), and an excellent sensitivity of 7.12 µAµM−1cm−2 were exhibited by the fabricated binary material based on SnO2/CdO MCs for selective p-nitrophenol capturing. In shortly, the SnO2/CdO MCs can be employed as an efficient electron mediator with binary materials fabricated GCE for capturing the p-nitrophenol at ultra-trace amounts. Then the binary synthesized material of SnO2/CdO MCs is used as potential and sensitive sensor layer by stable electrochemical approach for sensitive capturing of toxic p-nitrophenol from environmental samples.

Phosphate Ion-Modified RuO2/Ti3C2 Composite as a High-Performance Supercapacitor Material

Pseudocapitor materials, usually metal oxides, are used as active materials in an electrode to achieve high energy density. However, these kinds of materials often suffer from poor conductivity and high cost. Herein, a phosphate ion-modified RuO2/Ti3C2 composite is prepared via a chemical solution synthesis followed by an annealing process. In this composite material, Ti3C2 layers are introduced to improve the conductivity and the binary material is doped with phosphate ions into to increase the number of active reaction sites. As a result, the phosphate ion-modified RuO2/Ti3C2 delivers a high specific capacitance of 612.72 F g−1 at a current density of 2 A g−1 in H2SO4 electrolyte. What is more, the capacitance of the phosphate ion-modified RuO2/Ti3C2 can retain 97.95% (600.14 F g−1) of the original value even after 10,000 cycles at a current density of 2 A g−1.

Influence of anatase and rutile phase in TiO2 upon the photocatalytic degradation of methylene blue under solar irradiation in presence of activated carbon

The influence of activated carbon (AC) on the photocatalytic activity of different crystalline TiO2 phases was verified in the photocatalytic degradation of methylene blue under UV and solar irradiation. The results showed a volcano trend with a maximum photoactivity for the crystalline phase ratio of anatase:rutile equal to 80:20 both under UV or solar irradiation. By contrast, in presence of AC the photocatalytic activity of the binary materials of TiO2/AC followed an exponential trend, increasing as a function of the increase in anatase proportion in the TiO2 framework. The increase in the photoactivity of the binary material TiO2/AC relative to neat TiO2 was up to 22 and about 17 times higher under UV and visible irradiation, respectively. The present results suggest that AC interacts more efficiently with anatase phase than with rutile phase.

Mechano-Kinetic Coupling Approach for Materials With Evolutionary Internal Structure

Coupled multiscale approaches for the analysis and simulation of complex multiphysics phenomena in solids have been of great interest during the last decade. These include concurrent MD/FEM models, atomistic-to-continua homogenization techniques and deterministic multiple time scale approaches. In this paper we discuss a generic approach to concurrently couple the Monte-Carlo master equation of microscopic kinetic processes, not accessible by the direct particle dynamics, with the continuum mechanics formulation. This approach can be adequate for the modeling and validation of advanced contemporary materials with dynamic internal structure, as well as evolutionary and degradation processes in materials. The approach is illustrated in application to models of interstitial and vacancy diffusion in fuel cell catalysts and binary material systems.