Abstract: The disclosure relates to a wireless self-powered gas sensor based on electromagnetic oscillations triggered by external forces and its fabrication method. The sensor includes a gas test chamber, a first friction layer, a second friction layer, an interdigital electrode, a gas-sensitive material, an air inlet, an air outlet and leads. The gas sensor of the disclosure is an integrated detection system of “environmental energy collection—wireless energy transmission—active spontaneous detection” that can be driven simultaneously only by external mechanical movement, and can work independently without external power supply. The first friction layer and the second friction layer are arranged outside the gas test chamber. The frictional motion will not interfere with the flow field of the test chamber and the gas molecule absorption and desorption, which ensures the stability of gas detection to the greatest extent.

Abstract: A self-powered automobile exhaust gas sensor including a supporting frame, a ferroelectric-triboelectric coupling functional film, and two metal electrodes. The ferroelectric-triboelectric coupling functional film comprises a first end fixed on the supporting beam in middle of the supporting frame, and a second end is freestanding. The two metal electrodes are grounded and adhered on the upper and lower sides of the supporting frame, respectively. An iron block is mounted on the top of the supporting frame.

Abstract: A breathing-driven flexible respiratory sensor includes: a test cavity and a digital electrometer, wherein an upper internal wall of the test cavity is provided with an upper detecting component, and a lower internal wall of the test cavity is provided with a lower detecting component; the upper detecting component and the lower detecting component is arranged in a longitudinal symmetry form; wherein the upper detecting component comprises a substrate, an electrode and a gas sensitive film bonded in sequence from top to bottom, and the substrate is bonded to the upper internal wall of the test cavity; wherein a rubber airbag is disposed in the test cavity, and a friction film is bonded to the rubber airbag; an air inlet cylinder is connected to a left end of the rubber airbag, and an air outlet cylinder is connected to a right end of the rubber airbag.

Abstract: A three-dimensional folding self-driving flexible respiration monitoring sensor and the preparing method thereof is disclosed. In the present invention a first friction unit and a second friction unit are set on a bottom of the box, which comprise a substrate, a conductive electrode layer and a friction layer respectively; the second friction unit is fixed on the bottom of the box; a friction layer of the first friction unit faces a friction layer of the second friction unit; a back plate is set on a substrate of the first friction unit; a balloon is between the box and the back plate; an inlet tube connects the balloon and the box, which is on a side wall of the box; the conductive electrode layer of the first friction layer and the second friction layer are connected to the electrometer respectively. Micro-energy of the respiration is adopted to monitor the breathing.

Abstract: A one-step solution casting method for preparing a PVDF-based pyroelectric polymer film is provided, which belongs to the technical field of functional material preparation. The method comprises steps of: treating a substrate with a hydrophilic reagent to obtain a hydrophilically-modified substrate, and then casting the organic solution of polyvinylidene fluoride (PVDF) or its copolymer on the hydrophilically-modified substrate. After cured, the as-casted PVDF-based film shows pyroelectricity without undergoing any stretching or poling post-treatment, indicates that the dipoles of the one-step prepared film are aligned. The self-polarization of the prepared film is attributed to a hydrogen bond induced layer-by-layer electrostatic self-assembly growth mechanism. The method is simple, low cost, high efficient, high capability to produce thick and large-area film with smooth morphology and ease to be scalized.

Abstract: A self-powered automobile exhaust gas sensor including a supporting frame, a ferroelectric-triboelectric coupling functional film, and two metal electrodes. The ferroelectric-triboelectric coupling functional film comprises a first end fixed on the supporting beam in middle of the supporting frame, and a second end is freestanding. The two metal electrodes are grounded and adhered on the upper and lower sides of the supporting frame, respectively. An iron block is mounted on the top of the supporting frame.

Abstract: The disclosure relates to a wireless self-powered gas sensor based on electromagnetic oscillations triggered by external forces and its fabrication method. The sensor includes a gas test chamber, a first friction layer, a second friction layer, an interdigital electrode, a gas-sensitive material, an air inlet, an air outlet and leads. The gas sensor of the disclosure is an integrated detection system of “environmental energy collection—wireless energy transmission—active spontaneous detection” that can be driven simultaneously only by external mechanical movement, and can work independently without external power supply. The first friction layer and the second friction layer are arranged outside the gas test chamber. The frictional motion will not interfere with the flow field of the test chamber and the gas molecule absorption and desorption, which ensures the stability of gas detection to the greatest extent.

Abstract: A three-layer self-healing flexible strain sensor includes: a self-healing sensitive layer, wherein a self-healing encapsulating layer is respectively placed on an upper surface and a lower surface of the self-healing sensitive layer. The self-healing sensitive layer comprises a doped carbon material or a conductive composite. The three self-healing layers of the self-healing strain sensor can quickly repair the internal and external damage caused by the layered structure in a short period of time after the external damage, and does not require external stimulation. The three-layer self-healing structure strain sensor is simple in preparation without using a repair agent, which can achieve rapid self-repair at the room temperature, and can be repeatedly repair. The three-layer self-healing structure increases the strength and modulus of the strain sensor as well as increases the ability of the strain sensor to resist external damage.

Abstract: A three-dimensional folding self-driving flexible respiration monitoring sensor and the preparing method thereof is disclosed. In the present invention a first friction unit and a second friction unit are set on a bottom of the box, which comprise a substrate, a conductive electrode layer and a friction layer respectively; the second friction unit is fixed on the bottom of the box; a friction layer of the first friction unit faces a friction layer of the second friction unit; a back plate is set on a substrate of the first friction unit; a balloon is between the box and the back plate; an inlet tube connects the balloon and the box, which is on a side wall of the box; the conductive electrode layer of the first friction layer and the second friction layer are connected to the electrometer respectively. Micro-energy of the respiration is adopted to monitor the breathing.

Abstract: A breathing-driven flexible respiratory sensor includes: a test cavity and a digital electrometer, wherein an upper internal wall of the test cavity is provided with an upper detecting component, and a lower internal wall of the test cavity is provided with a lower detecting component; the upper detecting component and the lower detecting component is arranged in a longitudinal symmetry form; wherein the upper detecting component comprises a substrate, an electrode and a gas sensitive film bonded in sequence from top to bottom, and the substrate is bonded to the upper internal wall of the test cavity; wherein a rubber airbag is disposed in the test cavity, and a friction film is bonded to the rubber airbag; an air inlet cylinder is connected to a left end of the rubber airbag, and an air outlet cylinder is connected to a right end of the rubber airbag.

Abstract: A one-step solution casting method for preparing a PVDF-based pyroelectric polymer film is provided, which belongs to the technical field of functional material preparation. The method comprises steps of: treating a substrate with a hydrophilic reagent to obtain a hydrophilically-modified substrate, and then casting the organic solution of polyvinylidene fluoride (PVDF) or its copolymer on the hydrophilically-modified substrate. After cured, the as-casted PVDF-based film shows pyroelectricity without undergoing any stretching or poling post-treatment, indicates that the dipoles of the one-step prepared film are aligned. The self-polarization of the prepared film is attributed to a hydrogen bond induced layer-by-layer electrostatic self-assembly growth mechanism. The method is simple, low cost, high efficient, high capability to produce thick and large-area film with smooth morphology and ease to be scalized.

Abstract: A three-layer self-healing flexible strain sensor includes: a self-healing sensitive layer, wherein a self-healing encapsulating layer is respectively placed on an upper surface and a lower surface of the self-healing sensitive layer. The self-healing sensitive layer comprises a doped carbon material or a conductive composite. The three self-healing layers of the self-healing strain sensor can quickly repair the internal and external damage caused by the layered structure in a short period of time after the external damage, and does not require external stimulation. The three-layer self-healing structure strain sensor is simple in preparation without using a repair agent, which can achieve rapid self-repair at the room temperature, and can be repeatedly repair. The three-layer self-healing structure increases the strength and modulus of the strain sensor as well as increases the ability of the strain sensor to resist external damage.