The magnetocaloric(MC) effect-based solidstate magnetic refrigeration(MR) technology has been recognized as an alternative novel method to the presently commercialized gas compression technology. Searching for suitabl...The magnetocaloric(MC) effect-based solidstate magnetic refrigeration(MR) technology has been recognized as an alternative novel method to the presently commercialized gas compression technology. Searching for suitable candidates with promising MC performances is one of the most urgent tasks. Herein, combined experimental and theoretical investigations on the magnetic properties, magnetic phase transition, and cryogenic MC performances of Gd Fe_(2)Si_(2)have been performed. An unstable antiferromagnetic(AFM) interaction in the ground state has been confirmed in Gd Fe_(2)Si_(2). Moreover, a huge reversible cryogenic MC effect and promising MC performances in Gd Fe_(2)Si_(2)have been observed.The maximum isothermal magnetic entropy change, temperature-averaged entropy change with 2 K lift, and refrigerant capacity for Gd Fe_(2)Si_(2)were 30.01 J kg^(-1)K^(-1),29.37 J kg^(-1)K^(-1), and 328.45 J kg^(-1)at around 8.6 K with the magnetic change of 0–7 T, respectively. Evidently, the values of these MC parameters for the present AFM compound Gd Fe_(2)Si_(2)are superior to those of most recently reported rareearth-based MC materials, suggesting the potential application for active cryogenic MR.展开更多
The carbon dissolution in solvent plays a key role in the process of solution growth route for SiC single crystal,which could determine the growth rate and quality of the products.However,the carbon dissolving ability...The carbon dissolution in solvent plays a key role in the process of solution growth route for SiC single crystal,which could determine the growth rate and quality of the products.However,the carbon dissolving ability of binary alloy solvent still needs to be improved.Here,we demonstrate the improved carbon dissolution and enlarged carbon supersaturation in Cr-Ce-Si ternary solvent,showing great potential for SiC solution growth.The phase relations of Cr-Ce-Si-C system were determined by using CALPHAD method based on thermodynamic parameters of CeCr_(2)Si_(2)C.It is indicated that the Cr-Ce-Si ternary solvent shows much larger carbon solubility in temperature range from 1700 to 2000℃compared to Cr-Si binary one,Furthermore,the carbon supersaturation in solvent is also significantly increased in low temperature range after the addition of Ce,leading to a rapid growth rate.Our work not only demonstrates the feasibility of adding Ce in the alloy solvent for rapid growth of SiC crystal,but also provides an example for investigating the C solubility in ternary solvent.展开更多
基金supported by the National Key Research and Development Program of China(2022YFB3505101)the National Science Foundation for Excellent Young Scholars(52222107)+2 种基金the National Science Foundation for Distinguished Young Scholars(51925605)the Research Projects of Ganjiang Innovation Academy,Chinese Academy of Sciences(E055B002)the Doctoral Postgraduate Innovation Funding project of Hebei Province(CXZZBS2023032)。
基金financially supported by the National Natural Science Foundation of China (52071197)the “Pioneer” and “Leading Goose” R&D Program of Zhejiang (2022C01230)+1 种基金the Science and Technology Committee of Shanghai Municipality (19ZR1418300 and 19DZ2270200)the Independent Research and Development Project of State Key Laboratory of Advanced Special Steel, Shanghai Key Laboratory of Advanced Ferrometallurgy, Shanghai University (SKLASS 2021-Z05)。
文摘The magnetocaloric(MC) effect-based solidstate magnetic refrigeration(MR) technology has been recognized as an alternative novel method to the presently commercialized gas compression technology. Searching for suitable candidates with promising MC performances is one of the most urgent tasks. Herein, combined experimental and theoretical investigations on the magnetic properties, magnetic phase transition, and cryogenic MC performances of Gd Fe_(2)Si_(2)have been performed. An unstable antiferromagnetic(AFM) interaction in the ground state has been confirmed in Gd Fe_(2)Si_(2). Moreover, a huge reversible cryogenic MC effect and promising MC performances in Gd Fe_(2)Si_(2)have been observed.The maximum isothermal magnetic entropy change, temperature-averaged entropy change with 2 K lift, and refrigerant capacity for Gd Fe_(2)Si_(2)were 30.01 J kg^(-1)K^(-1),29.37 J kg^(-1)K^(-1), and 328.45 J kg^(-1)at around 8.6 K with the magnetic change of 0–7 T, respectively. Evidently, the values of these MC parameters for the present AFM compound Gd Fe_(2)Si_(2)are superior to those of most recently reported rareearth-based MC materials, suggesting the potential application for active cryogenic MR.
基金supported by the Beijing Municipal Science and Technology Commission Project(Z211100004821004)the National Natural Science Foundation of China(51872028)。
文摘The carbon dissolution in solvent plays a key role in the process of solution growth route for SiC single crystal,which could determine the growth rate and quality of the products.However,the carbon dissolving ability of binary alloy solvent still needs to be improved.Here,we demonstrate the improved carbon dissolution and enlarged carbon supersaturation in Cr-Ce-Si ternary solvent,showing great potential for SiC solution growth.The phase relations of Cr-Ce-Si-C system were determined by using CALPHAD method based on thermodynamic parameters of CeCr_(2)Si_(2)C.It is indicated that the Cr-Ce-Si ternary solvent shows much larger carbon solubility in temperature range from 1700 to 2000℃compared to Cr-Si binary one,Furthermore,the carbon supersaturation in solvent is also significantly increased in low temperature range after the addition of Ce,leading to a rapid growth rate.Our work not only demonstrates the feasibility of adding Ce in the alloy solvent for rapid growth of SiC crystal,but also provides an example for investigating the C solubility in ternary solvent.
基金supported by the National Key Research and Development Program of China(2021YFB3501202 and 2019YFB2005800)the Science Center of the National Science Foundation of China(52088101)+1 种基金the National Natural Science Foundation of China(51871019,52171170,52130103,51961145305,and 51971026)the 111 Project(B170003)。
