NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Solid state refrigeration based on caloric effect has been regarded as an attractive alternative to conventional gas compression technique. Boosting the caloric effect of a system to its optimum is a long-term pursuit. Here, we report enhanced magnetocaloric effect (MCE) and barocaloric effect (BCE) by hydrostatic pressure in La(Fe0.92Co0.08)11.9Si1.1 with NaZn13-type structure. The entropy change δSMCE is almost doubled under 11.31kbar, while the δSBCE is more than tripled under 9kbar. Neutron powder diffraction (NPD) studies were performed to disclose the origin of such pressure-enhanced MCE and BCE, . The NPD results revealed that hydrostatic pressure sharpens the magnetoelastic transition and enlarges the volume change, δV/V, during the transition through altering the intra-icosahedral Fe-Fe bonds rather than the intericosahedral distances in the NaZn13-type structure. First-principles calculations were performed, which supports the enlarged caloric effect related to the evolution of phase transition. Moreover, the enhanced lattice entropy change was calculated by Debye approximation, which is demonstrated to serve as a reliable way to evaluate BCE under a high pressure that DSC cannot reach. The present study proves that remarkable caloric effect enhancement can be achieved through tackling specific atomic environments by physical pressure, which may also be used to tailor other pressure related effects, such as controllable negative thermal expansion.
Hao, J.
, Hu, F.
, Wang, J.
, Shen, F.
, Yu, Z.
, Zhou, H.
, Wu, H.
, Huang, Q.
, Qiao, K.
, Wang, J.
, He, J.
, He, L.
, Sun, J.
and Shen, B.
(2020),
Large Enhancement of Magnetocaloric and Barocaloric Effects by Hydrostatic Pressure in La(Fe<sub>0.92</sub>Co<sub>0.08</sub>)<sub>11.9</sub>Si<sub>1.1</sub> with a NaZn<sub>13</sub>-Type Structure, Chemistry of Materials, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=929397
(Accessed October 10, 2025)