, and has been found to display the
greatest electrocaloric effect, i.e., change in temperature produced in
response to an electric field.
The findings of the study appear in the journal Nature
and could pave the way for developing highly effective solid-state (i.e.,
without gases) refrigerators and air conditioners
, overcoming the need to use
expensive and heavy magnets.
"When facing a challenge as big as climate
change and reducing carbon emissions
to net zero, we tend to focus on how we generate energy - and rightly so - but
it's critical that we're also looking at the consumption of energy,"
co-author Dr Xavier Moya from Cambridge's Department of Materials Science &
Producing Cooling Effect Using Electric Field
- The current study
included scientists from Cambridge in collaboration with teams at Japan
and Costa Rica
- In the current
study, the thermal changes in temperature are voltage driven. Using
voltage instead of pressure to drive cooling is easier from an engineering
point of view, and allows its application in existing designs, overcoming
the need for magnets
- The study team used
high-quality layers of PST with metal electrodes sandwiched in between.
This enabled the PST to withstand application of higher voltages, with
better cooling over a much wider range of temperatures
Previous Research to Produce Cooling Using Magnetic
- In fact, earlier
research teams have been trying to improve cooling technology by replacing
the current toxic gases with solid magnetic materials, such as gadolinium.
- However, they
observed that the performance of prototype devices was not as good as
expected, since changes in temperatures are driven by permanent magnets
with limited magnetic fields.
- In future
research, the team plan to employ high-resolution microscopy to examine
the PST microstructure, and determine if it can be optimized further to
make it withstand higher voltages
- The same
Cambridge-led team in a study published earlier this year, identified a
cheap, widely available solid material that could replace conventional
coolants when put under pressure. Developing this material for cooling
purposes needs a lot of redesigning, which is also being actively pursued
by the Cambridge team
In summary, the identification of a new cooling to replace
existing coolant gases that are toxic greenhouse gases could be good news for
the environment with regards to reducing the risk of global warming
and climate change.
- Large electrocaloric effects in oxide multilayer capacitors over a wide temperature range - (https://doi.org/10.1038/s41586-019-1634-0)