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In this paper, we introduce a modeling work on the variant reorientation in a single-crystalline Ni–Mn-Ga sample induced by a quasi-static rotating magnetic field. First, some constitutive assumptions are proposed for the variant state distribution, the effective magnetization and the elastic energy density of Ni–Mn-Ga alloys. Then, the total energy functional for a Ni–Mn-Ga sample subject to coupled magneto-mechanical loads is formulated. Through a variational approach, the governing equation system of the model can be formulated, which is composed of the magnetic and mechanical field equations, the evolution laws of some internal variables and the twin interface movement criteria. An efficient numerical scheme is adopted to solve the governing system. With the obtained numerical solutions, we first analyze the evolution properties of the configurational force on the twin interfaces. Especially, the effects of the application directions of magnetic fields on the configurational force are investigated. The influences of the different energy terms on the configurational force are also analyzed. Based on these results, we further conduct numerical simulations on the magneto-mechanical behavior of the Ni–Mn-Ga sample subject to a quasi-static rotating magnetic field. The predicted global responses of the Ni–Mn-Ga sample show good consistency with the experimental result. The configurations of the sample and the distributions of some important physical quantities in the sample during the different loading stages can also be described. Furthermore, by considering the properties of the configurational forces, the underlying mechanisms responsible for the rotating field-induced variant reorientations can be revealed. Image 1 • The response of a Ni–Mn-Ga sample subject to a rotating magnetic _eld is studied.. • The magneto-mechanical governing system is formulated through a varia-tional approach.. • The evolution properties of con_gurational forces on the twin interfaces are analyzed.. • The underlying mechanisms responsible for variant reorientations can be revealed.. • The global magneto-mechanical behavior of the Ni–Mn-Ga sample can be properly simulated.. [ABSTRACT FROM AUTHOR]

With the rapid development of industry, organic pollutants and bacterial contamination in water resources are becoming increasingly severe. Photocatalysis is an effective approach to address this problem. ZnO, as a traditional n- type semiconductor photocatalyst, has a relatively wide bandgap, which results in a narrow range of light absorption and quick recombination of photogenerated charge carriers, thus limiting its development. In this work, we constructed p -type CuO/ n -type ZnO heterojunction nanofibers (HNFs) to extend the light harvesting range and improve the migration and separation of the photoinduced electrons and holes across the hetero-interface through. Afterwards, Ag nanoparticles were introduced into above HNF matrix to reinforce the photocatalytic activity. Results showed that, upon simulated sunlight irradiation, the Ag NPs-decorated p- type CuO/ n- type ZnO HNFs exhibited enhanced photocatalytic activities. After 20 min of simulated sunlight irradiation, approximately 98.5% of MB was degraded by 1.0 at% Ag NPs-decorated p- type CuO/ n- type ZnO HNFs. Additionally, after 10 min of irradiation, the disinfection efficiency of HNFs for Escherichia coli was > 99.99%. It is worth noting that this study has opened up a new pathway for the rational design of p-n junction photocatalysts with superior charge transfer properties, to achieve remarkable photocatalytic disinfection and degradation activities. [Display omitted] • A p -type CuO/ n -type ZnO photocatalyst was prepared, leading to the broadening of photoabsorption in the visible region. • The CuO/ZnO nanofibers possess excellent photocatalytic activity for the degradation of MB and disinfection of E. coli. • To further enhance the activity of binary photocatalysts, Ag nanoparticles were successfully modified on CuO/ZnO HNFs. • Ag nanoparticles-modified CuO/ZnO HNFs photocatalysts exhibit rapid dye degradation and bactericidal activity (<30 min). [ABSTRACT FROM AUTHOR]

• TiO 2 /Cu 2 O/CuO CNFs is produced via a photoinduced phase-transition on the TiO 2 /CuO CNFs. • The TiO 2 /Cu 2 O/CuO CNFs exhibited the enhanced sensing property for glucose. • The sensitivity of TiO 2 /Cu 2 O/CuO CNFs depends on the TiO 2 content in the CNFs. • The sensing property of TiO 2 /Cu 2 O/CuO CNFs electrode is recoverable via the light irradiation. • The CNFs electrode possesses a good long-term stability, high anti-interference ability, and good reproducibility. The TiO 2 /Cu 2 O/CuO composite nanofibers (CNFs) were obtained via the photoinduced phase-transition process occurring in the electrospun TiO 2 /CuO CNFs. The TiO 2 /Cu 2 O/CuO CNFs electrode showed the higher sensitivity (2074.7 µA·mM−1·cm−2; 0–2 mM) than the pure CuO NFs, TiO 2 NFs, and TiO 2 / CuO CNFs electrodes, respectively. The enhanced glucose sensing performance is attributed to the existence of multiple valence-states and redox-couples in TiO 2 /Cu 2 O/CuO CNFs to promote the redox reaction. [Display omitted] Constructing metal-oxide-based composites with the multiple valence-states and redox-couples has been proved as an effective strategy to enhance the performance of non-enzymatic glucose sensing. Herein, we report a mild and efficient method to prepare multiple-valent copper-based oxide composite nanofibers (Cu x O CNFs) through introducing the TiO 2 photosensitizer into the CuO NFs for actuating the localized phase transition from tenorite CuO (Cu2+) to cuprite Cu 2 O (Cu+) upon UV–visible light irradiation. The sensitivity of the obtained TiO 2 /Cu 2 O/CuO CNFs for glucose sensing (0–2 mM) could be enhanced by 1.12–1.31 times as compared to that of the TiO 2 /CuO CNFs. The enhanced sensitivity is dependent on the TiO 2 -content in the primal TiO 2 /CuO CNFs. When introducing 5.0 at.% of TiO 2 into the CuO nanofibers, the photoinduced phase-transition process could result in the formation of optimal TiO 2 /Cu 2 O/CuO CNFs with the component ratio of Cu 2 O to CuO at 0.46:1. This TiO 2 /Cu 2 O/CuO CNFs (2074.7 µA·mM−1·cm−2; 0.25 µM) exhibited nearly 1.32-fold improvement on the sensitivity and 3.0-fold enhancement on the detection limit as compared to the corresponding values of the pure CuO electrospun nanofibers (1581 µA·mM−1·cm−2; 0.75 µM). After the continuous measurements for 14 days, the sensitivity of the optimal sample could maintain 89.4% of its initial value. Notably, its sensitivity could be further recovered to 97.4% of the initial value after UV–visible light irradiation for 1 h. [ABSTRACT FROM AUTHOR]

• TiO 2 was synthesized by a solvothermal method and treated with N-plasma at atmospheric pressure. • Ti3+ ions of N-TiO 2 form the Ti3+ self-doped system, which causing the light absorption range enhanced. • The catalytic H 2 evolution of N-TiO 2 is 14.85 times higher than that of the pristine TiO 2 NFs. [Display omitted] The N-TiO 2 was prepared by N-plasma treatment at room temperature and ambient, which caused the results of higher generation of oxygen vacancy. The reaction also resulted in reducing more Ti3+, and forming the Ti3+ self-doped system, changing the electronic structure of Ti3+, enhancing its light absorption range, and then enhancing its photocatalytic activity. The photocatalytic activity was ~14.85 times higher than that of the pristine TiO 2. An enhancement of the photocatalytic activity of Titanium dioxide nanosheets (TiO 2 NFs) by N 2 plasma (N-plasma) treatment has been suggested. TiO 2 NFs was synthesized by a solvothermal method and treated with N-plasma at atmospheric pressure. Then the as-prepared TiO 2 and N-plasma treated TiO 2 (N-TiO 2) NFs photocatalyst were extensively characterized. Interestingly, more oxygen vacancy and Ti3+ ions were found in the N-TiO 2 NFs. Meanwhile, Ti3+ ions form the Ti3+ self-doped system, which causing the light absorption range enhanced. The catalytic H 2 evolution of N-TiO 2 NFs at a rate of 8.1 mmol g−1 h−1, which is 14.85 times higher than that of the pristine TiO 2 NFs. These results might suggest new views for the photoactivity of TiO 2 NFs and provide a kind of feasibility for other metal oxides in the photocatalytic field. [ABSTRACT FROM AUTHOR]

In this work, homogeneous NiMoO 4 nanorods@hydrous NiMoO 4 nanosheets core/shell nanostructure were assembled on nickel foam by a two-step hydrothermal method and incorporate with an anneal process. Benefiting from their core/shell nanostructure and homogeneous nanocomposites, the arrays present high areal capacitance up to 6.34 F/cm2 at 4 mA/cm2 and display a remarkable specific capacitance retention of 89% after 5000 cycles. When the current density increases to 70 mA/cm2, the capacitance is 3.13 F/cm2 displayed good rate capability. The excellent electrochemical properties allow them to be used as a promising electrode material for pseudocapacitors, which has a wide application prospect in the field of electrochemical capacitor. • Controllable fabricated NiMoO 4 nanorods @hydrous NiMoO 4 nanosheets core/shell arrays by a two-step fabrication route. • The core/shell arrays present high areal capacitance. • The core/shell arrays displayed good rate capability. • Both "core" and "shell" electrochemical materials can be fully utilized and have a strong synergistic effect. [ABSTRACT FROM AUTHOR]