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Using X-ray diffraction (XRD) and a vibrating sample magnetometer (VSM), the effects of Sm substitution, wheel speed, and annealing temperature on the phase formation and magnetic properties of (Y1−xSmx)Co5 (x = 0.2, 0.3, 0.4, 0.5) melt-spun ribbons were investigated. The results indicate the following: (1) With the increase in Sm substitution, it was found that (Y1−xSmx)Co5 ribbons are entirely composed of the (Y-Sm)Co5 phase with a CaCu5-type structure. Additionally, the coercivity gradually increases, while the remanence and saturation magnetization gradually decrease. (2) As the wheel speed increases, the (Y1−xSmx)Co5 ribbons exhibit an increasing proportion of (Y-Sm)Co5 phase until reaching a speed of 40 m/s, where they are entirely composed of the (Y-Sm)Co5 phase. Magnetic measurements show that the coercivity (Hcj) and remanence (Br) of (Y0.5Sm0.5)Co5 ribbons increase gradually with increasing wheel speed, while saturation magnetization decreases. The variation in magnetic properties is mainly attributed to the formation of nucleation centers for reversed magnetic domain (2:7 and 2:17 phases); (3) (Y0.5Sm0.5)Co5 ribbons are composed of the (Y-Sm)Co5 phase and a small amount of the Sm2Co7 phase after annealing at 550 °C, 600 °C, and 650 °C. Temperature elevation promotes crystallization of the amorphous phase, resulting in a gradual decrease in coercivity, while the remanence and saturation magnetization exhibit an overall increasing trend. Through continuous optimization of the process, favorable magnetic properties were achieved under the conditions of a 0.5 Sm substitution level, a wheel speed of 40 m/s, and an annealing temperature of 550 °C, with a coercivity of 7.98 kOe, remanence of 444 kA/m, and saturation magnetization of 508 kA/m. [ABSTRACT FROM AUTHOR]

Aqueous aluminum-ion batteries (AIBs) have great potential as devices for future large-scale energy storage systems due to the cost efficiency, environmentally friendly nature, and impressive theoretical energy density of Al. However, currently, available materials used as anodes for aqueous AIBs are scarce. In this study, a novel sol-gel method was used to synthesize nitrogen-doped titanium dioxide (N-TiO2) as a potential anode material for AIBs in water. The annealed N-TiO2 showed a high discharge capacity of 43.2 mAh g−1 at a current density of 3 A g−1. Analysis of the electrode kinetics revealed that the N-TiO2 anodes exhibited rapid diffusion of aluminum ions, low resistance to charge transfer, and high electronic conductivity, enabling good rate performance. The successful implementation of a nitrogen-doping strategy provides a promising approach to enhance the electrochemical characteristics of electrode materials for aqueous AIBs. [ABSTRACT FROM AUTHOR]

The phase equilibrium and phase transformation of the Al–Si–Y ternary system were investigated in 80 annealed alloys using an electron probe microanalysis (EPMA), X-ray diffractometry (XRD) and differential scanning calorimetry (DSC). The phase equilibrium at 773 K was determined, and the phase distribution and solid solubility of the Al–Si–Y isothermal section at 773 K were obtained. A total of 23 three-phase zones and 4 two-phase zones were obtained, and 2 new ternary compounds, AlSi4Y5 and Al2Si3Y5, were identified from the non-aluminum-rich corner. Additionally, the phase transition temperatures of representative alloys were determined by the DSC method, and then the phase transition temperatures were processed to obtain the experimental points of vertical sections. In the Al–Si–Y alloy system, the phase diagrams of the vertical sections with X(Al) = 90 at.%, 80 at.%, 70 at.% and 60 at.% at the aluminum-rich corner were calculated, and then the experimental points were inserted into the vertical section phase diagrams. The results of the vertical sectional experiments obtained from the validation experiments are in good agreement with the vertical sectional data obtained from the calculations, indicating that the validated thermodynamic description is useful for the microstructure design of the aluminum-rich corner of the Al–Si–Y ternary alloy. [ABSTRACT FROM AUTHOR]

The isothermal section of the La–Co–Ni ternary system at 723 K has been constructed in this work by using X-ray diffraction (XRD), scanning electron microscopy, and energy dispersion spectroscopy techniques (SEM-EDS). The experimental results show no existence of ternary compounds at 723 K. The isothermal section consists of 16 two-phase regions and 8 three-phase regions. La3Co and La3Ni, La2Co3 and La2Ni3, La2Co7 and La2Ni7, and LaCo5 and LaNi5 form a continuous solid solution. The ternary solid solubility of Ni in LaCo13 phase and La2Co1.7 phase was determined to be 15.61 at.% and 9.61 at.%, respectively. The solid solubility of Co in the LaNi3, La7Ni3, and LaNi phases was 18.07 at.%, 5.62 at.%, and 8.49 at.%, respectively. The present experimental results are important for the design of La(Fe,Si)13-based magnetic refrigeration materials. [ABSTRACT FROM AUTHOR]

The phase structure and microstructure of Sm12Co88−xCux (x = 0, 2, 4, 6, 8, 10; at.%) as-cast alloys and melt-spun ribbons prepared via the arc-melting method and melt-spun technology were studied experimentally by X-ray diffraction (XRD) and scanning electron microscope (SEM) with energy dispersive spectroscopy (EDS). The results reveal that the Sm12Co88−xCux (x = 0) as-cast alloy contains Sm2Co17 and Sm5Co19 phases, while the Sm12Co88−xCux (x = 2) as-cast alloy is composed of Sm2Co17, Sm2Co7 and Sm(Co, Cu)5 phases. Sm2Co17 and Sm(Co, Cu)5 phases are detected in Sm12Co88−xCux (x = 4, 6, 8, 10) as-cast alloys. Meanwhile, Sm12Co88−xCux ribbons show a single SmCo7 phase, which is still formed in the ribbons annealed at 1023 K for one hour. After annealed at 1123 K for two hours, cooled slowly down to 673 K at 0.5 K/min and then kept for four hours, the ribbons are composed of Sm2Co17 and Sm(Co, Cu)5 phases. The magnetic measurements of Sm12Co88−xCux ribbons were performed by vibrating sample magnetometer (VSM). The results exhibit that the maximum magnetic energy product ((BH)max), the coercivity (Hcj) and the remanence (Br) of the Sm12Co88−xCux ribbons increase generally with the increase in Cu substitution. In particular, the magnetic properties of the ribbons annealed at 1123 K and 673 K increase significantly with the increase in Cu substitution, resulting from the increase in the volume fraction of the formed Sm(Co, Cu)5 phase after heat treatment. [ABSTRACT FROM AUTHOR]

Phase formation and microstructure of (Nd1-2xCexYx)14.5Fe79.3B6.2 (x = 0.05, 0.10, 0.15, 0.20, 0.25) alloys were studied experimentally. The results reveal that (Nd1-2xCexYx)14.5Fe79.3B6.2 annealed alloys show (NdCeY)2Fe14B phase with the tetragonal Nd2Fe14B-typed structure (space group P42/mnm) and rich-RE (α-Nd) phase, while (Nd1-2xCexYx)14.5Fe79.3B6.2 ribbons prepared by melt-spun technology are composed of (NdCeY)2Fe14B phase, α-Nd phase and α-Fe phase, except for the ribbon with x = 0.25, which consists of additional CeFe2 phase. On the other hand, magnetic properties of (Nd1-2xCexYx)14.5Fe79.3B6.2 melt-spun ribbons were measured by a vibrating sample magnetometer (VSM). The measured results show that the remanence (Br) and the coercivity (Hcj) of the melt-spun ribbons decrease with the increase of Ce and Y substitutions, while the maximum magnetic energy product ((BH)max) of the ribbons decreases and then increases. The tendency of magnetic properties of the ribbons could result from the co-substitution of Ce and Y for Nd in Nd2Fe14B phase and different phase constitutions. It was found that the Hcj of the ribbon with x = 0.20 is relatively high to be 9.01 kOe, while the (BH)max of the ribbon with x = 0.25 still reaches to be 9.06 MGOe. It suggests that magnetic properties of Nd-Fe-B ribbons with Ce and Y co-substitution could be tunable through alloy composition and phase formation to fabricate novel Nd-Fe-B magnets with low costs and high performance. [ABSTRACT FROM AUTHOR]

Antimony sulfide (Sb2S3) with a high theoretical capacity is considered as a promising candidate for Na-ion batteries (NIBs) and K-ion batteries (KIBs). However, its poor electrochemical activity and structural stability are the main issues to be solved. Herein, amorphous Sb2S3 nanospheres/carbon nanotube (Sb2S3/CNT) nanocomposites are successfully synthesized via one step self-assembly method. In-situ growth of amorphous Sb2S3 nanospheres on the CNTs is confirmed by X-ray diffraction, field-emission scanning electron microscopy, and transmission electron microscopy. The amorphous Sb2S3/CNT nanocomposites as an anode for NIBs exhibit excellent electrochemical performance, delivering a high charge capacity of 870 mA h g−1 at 100 mA g−1, with an initial coulomb efficiency of 77.8%. Even at 3000 mA g−1, a charge capacity of 474 mA h g−1 can be achieved. As an anode for KIBs, the amorphous Sb2S3/CNT nanocomposites also demonstrate a high charge capacity of 451 mA h g−1 at 25 mA g−1. The remarkable performance of the amorphous Sb2S3/CNT nanocomposites is attributed to the synergic effects of the amorphous Sb2S3 nanospheres and 3D porous conductive network constructed by the CNTs. [ABSTRACT FROM AUTHOR]

The phase structure and microstructure of Sm 12 Co 88-x Cu x (x = 0, 2, 4, 6, 8, 10; at.%) as-cast alloys and melt-spun ribbons prepared via the arc-melting method and melt-spun technology were studied experimentally by X-ray diffraction (XRD) and scanning electron microscope (SEM) with energy dispersive spectroscopy (EDS). The results reveal that the Sm 12 Co 88-x Cu x (x = 0) as-cast alloy contains Sm 2 Co 17 and Sm 5 Co 19 phases, while the Sm 12 Co 88-x Cu x (x = 2) as-cast alloy is composed of Sm 2 Co 17 , Sm 2 Co 7 and Sm(Co, Cu) 5 phases. Sm 2 Co 17 and Sm(Co, Cu) 5 phases are detected in Sm 12 Co 88-x Cu x (x = 4, 6, 8, 10) as-cast alloys. Meanwhile, Sm 12 Co 88-x Cu x ribbons show a single SmCo 7 phase, which is still formed in the ribbons annealed at 1023 K for one hour. After annealed at 1123 K for two hours, cooled slowly down to 673 K at 0.5 K/min and then kept for four hours, the ribbons are composed of Sm 2 Co 17 and Sm(Co, Cu) 5 phases. The magnetic measurements of Sm 12 Co 88-x Cu x ribbons were performed by vibrating sample magnetometer (VSM). The results exhibit that the maximum magnetic energy product ((BH) max ), the coercivity (H cj ) and the remanence (B r ) of the Sm 12 Co 88-x Cu x ribbons increase generally with the increase in Cu substitution. In particular, the magnetic properties of the ribbons annealed at 1123 K and 673 K increase significantly with the increase in Cu substitution, resulting from the increase in the volume fraction of the formed Sm(Co, Cu) 5 phase after heat treatment.