Researchers have developed a new material which has a great potential in the area of energy storage applications (i.e. capacitors). The new material is made of titanium dioxide doped (doping occurs when you deliberately add an impurity) with indium and niobium; it shows colossal permittivity, low dielectric loss, and stability with temperature.
Permittivity and Dialectrics
Permittivity is the amount of electrical resistance a material encounters when forming an electric field within itself. Dielectrics are materials that are nonconductive but have large permittivity values, so they can store the electric charge, i.e. electrical energy.
The relative permittivity (er) of a certain material is measured relative to the permittivity of vacuum (free space).
Materials with high permittivity are very important for electronic devices; they can store an electric charge and then release it in appropriate conditions. The term for the permittivity of materials with values of er higher than 10+3 is Colossal Permittivity (CP).
For a material to be effective for charge storage, it is important that the charge does not leak out and get wasted. The property measuring the capacity of a material to keep the charge is the dielectric loss (or dissipation factor); the lower the loss, the more efficient the material is at not dissipating the energy.
Generally a material with high permittivity does not have a low dielectric loss; this is especially true for materials showing colossal permittivity. Therefore, researchers must find a compromise between the two properties.
Capacitor Material Temperature Dependence
Further to the characteristics described above, a good capacitor material should work across a wide range of temperatures; in this way, we can use it for different applications and in varying environments. This means that both the permittivity and the dielectric loss should not change greatly with a change of temperature.
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