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Effects on substitution of Ge by In on structural and magnetic properties are studied in MnCoGe 1- x In x compounds. A small amount of In (2% and 5%) dopant can shift the martensite transformation temperature to room temperature and make it overlap with Curie temperature window, which results in a spin-lattice coupling and a large conventional magnetocaloric effect. Giant values of magnetic entropy change ( △S M ) are obtained in both magnetizing and demagnetizing processes in the vicinity of the magnetostructural transition. The maximum values of | △S M | for MnCoGe 0.95 In 0.05 reach 21.4 and 25.4 J/kg K for a small magnetic field change △H  = 2–0 and 0–2 T, respectively, which make it promising for room temperature magnetic refrigeration applications. [ABSTRACT FROM AUTHOR]

Abstract: The magnetic properties and magnetocaloric effect of C15 Laves phase TbMn1.8Fe0.2 were studied by magnetization and heat capacity measurements. The compound undergoes a second-order magnetic Tb–Tb sublattice ordering transition at its Curie temperature T C ∼80K, and a Fe–Fe ordering transition at ∼230K. A large magnetocaloric effect was observed around Tb–Tb ordering temperature with no obvious thermal and magnetic hysteresis loss. The maximum value of magnetic entropy change reaches 9.48Jkg−1 K−1 for a magnetic field change ΔH =5T. The corresponding maximum adiabatic temperature change is evaluated to be 3.5K with a wide effective temperature range. The obtained relative cooling power reaches 235, 607, and 869Jkg−1 for ΔH =2, 5 and 7T, respectively. These values indicate that TbMn1.8Fe0.2 could be a promising candidate for magnetic refrigeration. [Copyright &y& Elsevier]

The combination of photocatalysis technology and Fenton technology to realize photo-Fenton degradation of organic pollutants is an effective way to improve the catalytic performance of materials. In this paper, a novel heterojunction photo-Fenton catalyst MIL-88A@TiO 2 (MT-X) has been prepared using MIL-88A and TiO 2 as substrate by one-pot hydrothermal method. The formation of MT-X heterogeneous structure not only improves the electron-hole separation performance of the composites, but also accelerates the regeneration of Fe2+. Under the synergistic action of photocatalysis and Fenton catalysis, MT-2 with the best performance can completely degrade methylene blue (MB, 100 mL, 20 mg/L) within 16 min and can mineralize 76.23 % MB into small molecule products. Meanwhile, MT-2 also has excellent adsorption and degradation properties for tetracycline (TC), which can degrade 99 % TC (100 mL, 50 mg/L) within 20 min, the reaction kinetic constant k = 0.27938 min‐1 is higher than most reported photocatalysts. Hydroxyl radical is identified as the main active species in the degradation process by quenching and hydroxyl radical capture experiments, and a possible degradation mechanism is proposed (Z-scheme electron transfer mechanism). Therefore, this study provides an efficient and feasible photo-Fenton catalyst for pollutant treatment, which is helpful to further understand the synergistic effect of photocatalysis and Fenton catalysis. • The synergistic effect of photocatalysis and Fenton technology was successfully utilized. • The synergetic mechanism of photocatalysis and Fenton technology was deeply analyzed. • MIL-88A@TiO 2 has excellent universal degradation performance for a variety of dyes. • MIL-88A@TiO 2 has excellent adsorption and degradation performance for TC. [ABSTRACT FROM AUTHOR]

A series of cadmium oxide samples (CdOs) were synthesized by thermal treatment method with various annealing temperatures (T A = 500 ℃ - 900 ℃). All samples crystallize in a pure cubic structure with Fm 3 ̅ m symmetry. The crystallite size, lattice parameter and volume change slightly with T A , and show an unexpected inflection point for the sample with T A = 800 ℃ (CdO-800), while the average particle size increases monotonically from ∼0.4 µm to ∼3.0 µm. Distinct ferromagnetic features accompanied by diamagnetic and/or paramagnetic phases were detected. The XPS data indicate the valence of cadmium and oxygen vacancy concentration varies with T A , which are responsible for the ferromagnetic origin in CdOs. CdO-800 shows the maximum magnetization, significant coercive force and residual magnetization. Oxygen vacancy plays a crucial role in the ferromagnetic performance, which can be effectively controlled by changing the sintering temperature. This work claims new characteristics for CdO besides optical and semi-conducting, which may be important in the preparation and possible applications for CdO dilute magnetic semiconductors. • The lattice parameter and grain size of CdO vary with annealing temperature. • The ferromagnetism of CdO stems from Cd and O vacancies. • This work claimed new characteristics for CdO besides optical and semi-conducting. [ABSTRACT FROM AUTHOR]

Nanostructured WO 3 films prepared by an industry compatible method with large surface area and strong adhesive force to the substrate are highly desired for electrochromic (EC) applications. Here, we report the preparation of a kind of WO 3 nanoisland films on indium-doped tin oxide (ITO)-coated glass substrates by Ag-induced reactive sputtering deposition combined with a post-etching treatment. Our study demonstrates that compared with the bare WO 3 film, the nanoisland film exhibits apparently enhanced EC performance, including high luminous transmittance (92.8%) in a bleached state, high luminous coloration efficiency (126.4 cm2/C), relatively fast color-switching time (7.1 s for coloring and 12.1 s for bleaching), decent long-term cycling stability (2000 cycles) and improved self-bleaching ability. Electrochemical kinetics analysis indicates that such enhanced EC performance relies on large lithium-ion diffusion coefficient (2.37 × 10−10 cm2/s), a good ability of charge storage (10.82 mF/cm2), and low charge-transfer resistance (196 Ω) of the nanoisland microstructure. The results shed light on exploring a novel method to prepare high EC performance WO 3 film. Image 1 • WO 3 nanoisland films can be fabricated by Ag-induced magnetron sputter deposition combined with a post-etching treatment, which significantly increases the contact interface between the electrolyte and materials. • The special nanostructure promotes the electrochromic performance eminently: higher optical transmittance (92.8%), coloration efficiency (126.4 cm2/C) and fast response time (7.1 s for coloring and 12.1 s for bleaching). • The electrochemical performance was analyzed to explain the internal cause relying on large ion diffusion coefficient (2.37 × 10−10 cm2/s), good charge storage (10.82 mF/cm2), and low charge-transfer resistance (196 Ω). [ABSTRACT FROM AUTHOR]