Bending ice Generates Electricity, New Research Reveals-Possibly Solving Lightning Mystery
New discoveries demonstrate that ice produces electricity when mechanically stressed, offering a potential explanation for charge generation in thunderstorms and opening doors for novel electronic applications.
Scientists have discovered that ice exhibits two distinct mechanisms for generating electricity depending on temperature. Below -113 °C, the surface layer of ice becomes ferroelectric. From -113 °C up to 0 °C, the entire ice structure can produce charge through flexoelectricity-the generation of electrical polarization in response to mechanical strain.
The research, published recently, coudl resolve a long-standing question in atmospheric science: how lightning forms within clouds. While collisions between ice crystals and graupel (soft hail) are known to create charge separation, ice was previously considered non-piezoelectric, leaving the source of the charge unexplained.
The new study proposes that the bending,denting,and deformation during these collisions trigger flexoelectric polarization,creating electric fields and attracting charges. As the particles separate, one retains more electrons than the other, resulting in charge separation.
“The calculated flexoelectric polarization during a typical ice-graupel collision reaches ~10⁻ C/m on the graupel surface,” the authors wrote. This level of polarization, they argue, aligns with charge measurements from laboratory experiments simulating storm cloud electrification. Furthermore, the direction of charge transfer observed in the study correlates with observed polarity reversals in real thunderstorms.
Researchers acknowledge that other factors, such as fracturing, friction, and impurity diffusion, likely contribute to charge generation in clouds, but suggest flexoelectricity is a significant component.
Beyond understanding weather phenomena, the strength of ice’s flexoelectric effect-comparable to that of materials like titanium dioxide and strontium titanate-suggests potential applications in electronics. This opens the possibility of creating low-cost, temporary electronic devices for use in cold environments.
“This finding could pave the way for the development of new electronic devices that use ice as an active material, which could be fabricated directly in cold environments,” said Prof. Catalán. Potential applications include sensors embedded in glaciers or energy-harvesting surfaces on frozen satellites.
