A sensor for determining plural parameters includes a housing that defines a chamber and a parallel plate capacitor having a first plate located inside the chamber and a second plate fixedly attached to a first external side of the housing. A dielectric multi-layer placed between the first and second plates includes a pressure sensitive layer and a humidity sensitive layer.

An example power generation system includes two capacitors and an electric load. A first capacitor includes a dielectric material that is configured to transition from a ferroelectric phase to a paraelectric or antiferroelectric phase when heated above a first transition temperature, and to transition from the paraelectric or antiferroelectric phase to the ferroelectric phase when cooled below a second transition temperature. A second capacitor is electrically coupled in parallel to the first capacitor. The electric load is electrically coupled to the first capacitor and the second capacitor. The system is configured to cyclically cool the dielectric material below the second transition temperature to draw a charge from the second capacitor to the first capacitors through the electric load, and heat the dielectric material beyond the first transition temperature to draw a charge from the first capacitor to the second capacitors through the electric load.

An example power generation system includes two capacitors and an electric load. A first capacitor includes a dielectric material that is configured to transition from a ferroelectric phase to a paraelectric or antiferroelectric phase when heated above a first transition temperature, and to transition from the paraelectric or antiferroelectric phase to the ferroelectric phase when cooled below a second transition temperature. A second capacitor is electrically coupled in parallel to the first capacitor. The electric load is electrically coupled to the first capacitor and the second capacitor. The system is configured to cyclically cool the dielectric material below the second transition temperature to draw a charge from the second capacitor to the first capacitors through the electric load, and heat the dielectric material beyond the first transition temperature to draw a charge from the first capacitor to the second capacitors through the electric load.

A switchable metal insulator metal capacitor (MIMcap) and a method for fabricating the MIMcap. In another aspect of the invention operating the MIMcap is also described. A first capacitor plate and a second capacitor plate are separated by a capacitor dielectric and disposed over a substrate. A first via is electrically connected to the first capacitor plate and comprised of phase change material (PCM). The PCM is deposited in an electrically conductive state and convertible by application of heat to an insulating state. A first heater is proximate to and electrically isolated from the PCM in the first via. When the first heater is activated it converts the PCM in the first via to the insulating state. This isolates the first capacitor plate from an integrated circuit.

The present disclosure provides an energy conversion system and method for generating electricity directly from heat by phase transformation of ferroelectric materials without any external power sources. The energy conversion system includes an electric circuit comprising a phase-changing capacitor and a charge reservoir. The phase-changing capacitor has a dielectric layer comprising a phase-transforming ferroelectric material. When the phase-changing capacitor is initialized and subjected to thermal cycles through a transformation temperature of the phase-transforming ferroelectric material, the polarization of the dielectric layer undergoes an abrupt change between a ferroelectric phase and a paraelectric phase such that a current flow between the phase-changing capacitor and the charge reservoir via a load thereby converting heat into electrical energy. The present energy conversion method does not require any external bias fields during the energy conversion.

The present disclosure provides an energy conversion system and method for generating electricity directly from heat by phase transformation of ferroelectric materials without any external power sources. The energy conversion system includes an electric circuit comprising a phase-changing capacitor and a charge reservoir. The phase-changing capacitor has a dielectric layer comprising a phase-transforming ferroelectric material. When the phase-changing capacitor is initialized and subjected to thermal cycles through a transformation temperature of the phase-transforming ferroelectric material, the polarization of the dielectric layer undergoes an abrupt change between a ferroelectric phase and a paraelectric phase such that a current flow between the phase-changing capacitor and the charge reservoir via a load thereby converting heat into electrical energy. The present energy conversion method does not require any external bias fields during the energy conversion.

A capacitive sensor is disclosed. The capacitive sensor includes a substrate, a first electrode and a second electrode formed on the substrate, an insulation layer formed on the substrate on which the first electrode and the second electrode are formed, and a sensing layer that is formed on the insulation layer and includes graphene.

Provided is a system for directly sensing, measuring, or monitoring the temperature of an electrical conductor (31) of a power cable (10). A temperature sensitive capacitor (21C) is disposed in direct thermal contact with the electrical conductor (31). The temperature sensitive capacitor (21C) includes a dielectric material that has a dielectric constant variable with the temperature of the electrical conductor (31). The temperature of the electrical conductor (31) can be sensed, measured, or monitored by measuring the capacitance of the temperature sensitive capacitor (21C).

Provided is a system for directly sensing, measuring, or monitoring the temperature of an electrical conductor (31) of a power cable (10). A temperature sensitive capacitor (21C) is disposed in direct thermal contact with the electrical conductor (31). The temperature sensitive capacitor (21C) includes a dielectric material that has a dielectric constant variable with the temperature of the electrical conductor (31). The temperature of the electrical conductor (31) can be sensed, measured, or monitored by measuring the capacitance of the temperature sensitive capacitor (21C).

A passive temperature-sensing apparatus, which includes a capacitive sensing element that includes a capacitive sensing composition that includes a ferroelectric ceramic material that exhibits a measurable electrical Curie temperature that is below 30 degrees C. The capacitive sensing composition exhibits a negative slope of capacitance versus temperature over the temperature range of from 30 degrees C. to 150 degrees C.