Abstract The efficient coupling between lattice degrees of freedom and spin in magnetic materials can be used for refrigeration energy conversion. This is enhanced exhibiting the giant magnetocaloric effect. First principle electronic structure calculations on hexagonal MnFe(P, Si) reveal a new form magnetism: coexistence strong weak magnetism alternate atomic layers. Fe layers (disappearance local moments at Curie temperature) responsible with crystal while adjacent Mn‐layers ensures...

We report on structural, magnetic and magnetocaloric properties of MnxFe1.95-xP0.50Si0.50 (x > 1.10) compounds. With increasing the Mn:Fe ratio, a first-order magneto-elastic transition gradually changes into magneto-structural via second-order transition. The study also shows that thermal hysteresis can be tuned by varying ratio. Small (less than 1 K) obtained while maintaining giant effect. This achievement paves way for real refrigeration applications using refrigerants.

Activated carbon was prepared from Moringa oleifera leaf by NaOH activation (ACB), and applied to remove methylene blus (MB) aqueous solution. The ACB characterized scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), Fourier Transform-Infrared Spectroscopy (FT-IR). isoelectric point of ACB, pHzpc = 8. Investigation some factors affecting the adsorption capacity method static results: time reach equilibrium is 90 min. best pH for MB 7, adsorbent dosage 1.67 g/L. on...

Hole-doped manganese oxides exhibit a gigantic negative magnetoresistance, referred to as colossal magnetoresistance (CMR), owing the interplay between double-exchange (DE) ferromagnetic metal and charge-ordered antiferromagnetic insulator/semiconductor phases. Magnetoresistive manganites display sharp resistivity drop at metal–insulator transition temperature (TMI). CMR effects in perovskite manganites, specifically La0.67Ca0.33MnO3 (La-Ca-Mn-O or LCMO), have been extensively investigated....

Using high-resolution neutron diffraction measurements for Mn-rich hexagonal Mn-Fe-P-Si compounds, we show that the substitution of Mn Fe on 3$f$ sites results in a linear decrease Fe/Mn(3$f$) magnetic moments, while Mn(3$g$) moments remain constant. With increasing temperature, almost no change, quickly when transition temperature is approached. The reduction at and high-temperature range discussed based changes interatomic distances lattice parameters magnetic-susceptibility measurement.

Neutron-diffraction experiments on the (Mn,Fe)${}_{2}$(P,Si)-type compounds have shown a site preference of Si atoms in hexagonal structure. The degree ordering depends Si/P ratio, while it is independent Mn/Fe ratio. ferromagnetic-paramagnetic magnetoelastic transition closely related to size magnetic moment 3$f$ site. A preferred occupation 2$c$ stabilizes and decreases 3$g$ site, respectively, which supported by our first-principles density functional theory calculations. This effect,...

Magnetic and magnetocaloric properties of high-purity, giant polycrystalline single-crystalline Fe${}_{2}$P are investigated. displays a moderate magnetic entropy change, which spans over 70 K the presence strong magnetization anisotropy proves this system is not fully itinerant but mix localized magnetism. The pure compared to those (Fe,Mn)${}_{2}$(P,$A$) (where $A=\text{As}$, Ge, Si) compounds helping understand exceptional characteristics shown by latter, so promising for heat pump energy...

In this study, we adopted the solution combustion method to synthesize magnesium ferrite (MgFe 2 O 4 ) using urea as fuel. Various techniques including TGA, XRD, SEM, TEM, FTIR, UV-Vis DRS, and EDS were employed characterize synthesized MgFe nanoparticles. The XRD analysis revealed that single-phase was formed at a calcination temperature of 500–600°C for 3 hours in absence an intermediate phase. TEM also formation monodisperse nanoparticles, averaged 30 nm size. photocatalytic activity...

Abstract Carbon materials is a commonly used electrode material because of its low cost, good conductivity, and structure that allows lithium ions to intercalate between layers in the carbon network. In this article, nanomaterials (CP) have been successfully manufactured from Vietnamese coal. CP two-dimensional, leaf-shaped nanomaterial with specific surface area 16.7799 m 2 ·g −1 . symmetric supercapacitor system, has high capacitance rate 275 F·g current density 0.1 A·g , an energy 6.4 W...

Bài báo này trình bày kết quả chế tạo điện cực biến tính Graphene/ITO bằng phương pháp lắng đọng di graphene lên đế ITO, ứng dụng làm cảm không enzyme xác định axit uric. Hình thái và cấu trúc của cũng như được mô tả kính hiển vi tử quét quang phổ Raman. Đặc trưng hóa khảo sát để đánh giá tiềm năng vật liệu. Các cho thấy có phạm tuyến độ nhạy với hai khoảng tương là: thứ nhất nồng từ 10–100 µM (R2 = 0,99763), là 0,22094 (µAcm–2µM–1); 100–2000 0,99617), 0,05462 (µAcm–2µM–1). Kết gợi mở nhiều...

This study explores the synergistic therapeutic potential of Prussian Blue Erbium-Doped Hydroxyapatite (PB-Er-HAp) bioceramics in context photothermal therapy (PTT) and photodynamic (PDT) for cancer treatment, highlighting their role multimodal approaches imaging. PB-Er-HAp nanoparticles (NPs) were synthesized using a facile coprecipitation method to incorporate erbium (Er) into nanostructured hydroxyapatite (HAp) at various concentrations. (PB) was functionalized onto surfaces these NPs,...

The electrodes in photoelectrochemical cells responsible for the generation of hydrogen and oxygen by water splitting have been intensively studied because their high photon-to-electron conversion efficiency. morphology nanostructures with these high-efficiency was systematically compared ZnO structures vertically aligned nanorod arrays (NA), hollow hemisphere (HA), urchin-like (UL) arrays, thin films (TF). UV-vis light absorption, photoresponse (current–voltage characteristics dark under...

Heavy metal pollution in the soil environment is a worldwide environmental problem as it has negative effects on both human health and environment. Remediation of heavy metal-contaminated essential to improve quality, provide land resources for agricultural production, protect animal ecological There possibility remediating these contaminated soils through use several absorbing plants Superabsorbent polymers. polymers (SAPs) are 3D polymer networks having hydrophilic nature, which can swell,...

Cuprous oxide/copper/cupric oxide nanoparticles were synthesized through a hybrid process involving anodic dissolution and controlled redox reaction between NaOH glucose in the solution. The study demonstrates structural manipulation of material by varying components within Morphology, analyses using SEM (Scanning Electron Microscope), EDX (Energy-dispersive X-ray spectroscopy), TEM (Transmission FTIR (Fourier Transform Infrared Spectroscopy), XRD (X-ray diffraction), XPS photoelectron...