Magnetocaloric effect: From materials research to refrigeration devices

In the past 20 years, there has been a surge in research on the magnetocaloric response of materials, due mainly to the possibility of applying this effect for magnetic refrigeration close to room temperature. This review is devoted to the main families of materials suitable for this application and to the procedures proposed to predict their response. Apart from the possible technological applications, we also discuss the use of magnetocaloric characterization to gain fundamental insight into the nature of the underlying phase transition.

The Magnetocaloric Effect and Magnetic Refrigeration Near Room Temperature: Materials and Models

and Perspectives Sophie Carenco,†,‡,§,∥,⊥ David Portehault,*,†,‡,§ Ced́ric Boissier̀e,†,‡,§ Nicolas Meźailles, and Cleḿent Sanchez*,†,‡,§ †Chimie de la Matier̀e Condenseé de Paris, UPMC Univ Paris 06, UMR 7574, Colleg̀e de France, 11 Place Marcelin Berthelot, 75231 Paris Cedex 05, France ‡Chimie de la Matier̀e Condenseé de Paris, CNRS, UMR 77574, Colleg̀e de France, 11 Place Marcellin Berthelot, 75231 Paris Cedex 05, France Chimie de la Matier̀e Condenseé de Paris, Colleg̀e de France, 11 Place Marcellin Berthelot, 75231 Paris Cedex 05, France Laboratory Heteroelements and Coordination, Chemistry Department, Ecole Polytechnique, CNRS-UMR 7653, Palaiseau, France

Nanoscaled metal borides and phosphides: recent developments and perspectives

Multiferroic bismuth ferrite-based materials for multifunctional applications: Ceramic bulks, thin films and nanostructures

Sources of anthropogenic radionuclides in the environment: a review

Radioactivity concentrations in soils of the Xiazhuang granite area, China.

The investigation of 137Cs and 90Sr background radiation levels in soil and plant around Tianwan NPP, China.

Thermal decomposition of iron oxychloride as studied by thermal analysis, X-ray diffraction and Mössbauer spectroscopy

The original palygorskite clay mineral has been collected from Longwangshan, Xuyi, Jiangsu Province, China. XRF analysis was performed to study its chemical compositions. Thermogravimetric analysis and differential thermogravimetric analysis (TGA/DTA) were used to study the weight loss due to dehydration and dehydroxylation. Then eight samples were prepared by heating at various temperatures. X-ray diffraction (XRD) patterns and Mossbauer spectra were measured to study the crystal evolvement and the occupation of iron cations. It revealed that the iron ions occupied the M1 and M2 with the ratio closed to 3:1. Hematite has been observed when heated at 650 °C, which indicated that iron cations mainly occupy M1 sites. An unknown silicate was identified when heated at 750 °C and dominated at 850 °C.

Mössbauer investigations of palygorskite from Xuyi, China

Eu1−xSrxFeO3 (x=0, 1/4, 1/3, 1/2, 2/3 and 1) perovskites were prepared using conventional solid-state method. Structure aspects of the Eu1−xSrxFeO3 were studied by powder X-ray diffraction. The results showed that Eu1−xSrxFeO3 (x=0, 2/3) was single phase with orthorhombically distorted structure. For samples with x=1/4, 1/3 and 1/2, phase segregation was observed. The Mossbauer spectra showed that Fe4+ appeared as the Eu3+ was replaced by Sr2+, EuFeO3-like phase existed in systems with x=1/4, 1/3 and 1/2. The corresponding oxygen vacancies were also calculated from the Mossbauer spectra.

Yuanfu Hsia

Papers

Radioactivity concentrations in soils of the Xiazhuang granite area, China.

The investigation of 137Cs and 90Sr background radiation levels in soil and plant around Tianwan NPP, China.

Thermal decomposition of iron oxychloride as studied by thermal analysis, X-ray diffraction and Mössbauer spectroscopy

Mössbauer investigations of palygorskite from Xuyi, China

XRD and Mössbauer investigation of phase segregation in Eu1−xSrxFeO3