Abstract: A piezoelectric strain sensor and method thereof for detecting strain, vibration, and/or pressure. The sensor incorporates a sequence of piezoelectric and semiconductor layers in a thin-film transistor structure. The thin-film transistor structure can be configured on a flexible substrate via a low-cost fabrication technique. The piezoelectric layer generates an electric charge resulting in a modulation of a transistor current, which is a measure of external strain. The sensor can be formed as a single gate field-effect piezoelectric sensor and a dual gate field-effect piezoelectric sensor. The semiconductor layer can be configured from a nanowire array resulting in a metal-piezoelectric-nanowire field effect transistor. The single and dual gate field-effect piezoelectric sensor offer increased sensitivity and device control due to the presence of the piezoelectric layer in the transistor structure and low cost manufacturability on large area flexible substrates.

Abstract: Methods can be adapted for design of a sensitive monolayer for detection of hydrogen sulphide at room temperature with SAW/BAW devices. The sensitive monolayer can be synthesized based on chemical compounds, which belongs to a class of thiacalix[n]arenas, mercapto halides, mercapto alcohols and chloromethylated thiacalix[n]arenas. The sensitive monolayer can be directly immobilized or anchored at the surface of a piezoelectric quartz substrate in a covalently bonded manner by means of direct printing process. The piezoelectric quartz substrate can be activated in basic medium or in acid medium before the immobilization of the sensitive monolayer in order to increase the population of OH groups. Thus, the synthesized sensitive monolayer exhibits a high site density, fast response and long-term stability for H2S sensing.

Abstract: A solar cell comprisies a photovoltaic material and at least one polymer layer. In a further embodiment, a first polymer layer is electrically coupled to the photovoltaic material and has a high density of defects to facilitate hole transfer, and a second layer is electrically coupled to the first polymer layer and has a low density of defect states to facilitate hole transport.

Abstract: A method can be adapted for design and preparation of a matrix nanocomposite sensing film for hydrogen sulphide SAW/BAW detection at room temperature. A matrix nanocomposite can be synthesized by incorporating both single-wall and multi-wall thiolated carbon nanotubes into conductive organic polymers or ceramic nanocrystalline in a properly functionalized manner. A thin organic sensing film can be prepared based on the matrix nanocomposite. The matrix nanocomposite sensing film can be prepared on a surface of a SAW/BAW device by an additive process or a direct printing process. Finally, the sensing film can be consolidated by thermal annealing or laser annealing under ambient conditions in order to obtain the stable sensing film with higher sensitivity and electrical properties for a SAW/BAW based H2S sensor.

Abstract: A solar cell includes multiple organic materials (including at least one donor material and at least one acceptor material) and multiple inorganic materials. The organic and inorganic materials collectively form multiple hybrid heterojunction structures. Each hybrid heterojunction structure includes at least two organic materials and at least one inorganic material. A first of the inorganic materials could include nanowires and/or nanotubes, and a second of the inorganic materials could include nanoparticles and/or quantum dots. At least some of the nanoparticles or quantum dots could have different sizes, where the different sizes are associated with different absorption bandgaps. Excitons photo-generated in at least one of the organic materials may dissociate into holes and electrons. Also, electrons and holes photo-generated in at least one of the inorganic material may separate. Further, one or more of the inorganic materials may transport at least some of the electrons towards one of multiple electrodes.

Abstract: Solar cells and solar cell assemblies that may be tuned for greater sensitivity to particular ranges of energy within the electromagnetic spectrum. In some instances, a solar cell may include a tunable electron conductor that permits greater choices in quantum dots, thereby providing solar cells that can be constructed to utilize a larger fraction of the solar spectrum. In some cases, the electron conductor may include group III nitride-based materials. A solar cell assembly is also disclosed that may include a first quantum dot solar cell and a second quantum dot solar cell. The first and second quantum dot solar cells may be tuned for differing portions of the electromagnetic spectrum.

Abstract: Example solar cells and methods for making and using the same are disclosed. An example solar cell may include an electron conductor layer, a quantum dot layer, a bifunctional ligand layer coupling the electron conductor layer and the quantum dot layer, and a hole conductor layer coupled to the quantum dot layer. The bifunctional ligand layer may include an antibiotic, and in some cases, a cephalosporin-based antibiotic.

Abstract: A solar cell including a quantum dot and an electron conductor, and a bifunctional ligand disposed between the quantum dot and the electron conductor. The bifunctional ligand molecule may include an electron conductor anchor that bonds to the electron conductor and a first quantum dot anchor that bonds to the quantum dot. A hole conductor such as a conductive polymer may include a second quantum dot anchor.

Abstract: A method can be adapted for design and preparation of a matrix nanocomposite sensing film for hydrogen sulphide SAW/BAW detection at room temperature. A matrix nanocomposite can be synthesized by incorporating both single-wall and multi-wall thiolated carbon nanotubes into conductive organic polymers or ceramic nanocrystalline in a properly functionalized manner. A thin organic sensing film can be prepared based on the matrix nanocomposite. The matrix nanocomposite sensing film can be prepared on a surface of a SAW/BAW device by an additive process or a direct printing process. Finally, the sensing film can be consolidated by thermal annealing or laser annealing under ambient conditions in order to obtain the stable sensing film with higher sensitivity and electrical properties for a SAW/BAW based H2S sensor.

Abstract: Methods can be adapted for design of a sensitive monolayer for detection of hydrogen sulphide at room temperature with SAW/BAW devices. The sensitive monolayer can be synthesized based on chemical compounds, which belongs to a class of thiacalix[n]arenas, mercapto halides, mercapto alcohols and chloromethylated thiacalix[n]arenas. The sensitive monolayer can be directly immobilized or anchored at the surface of a piezoelectric quartz substrate in a covalently bonded manner by means of direct printing process. The piezoelectric quartz substrate can be activated in basic medium or in acid medium before the immobilization of the sensitive monolayer in order to increase the population of OH groups. Thus, the synthesized sensitive monolayer exhibits a high site density, fast response and long-term stability for H2S sensing.

Abstract: A solar cell including a quantum dot and an electron conductor, with a bifunctional ligand disposed between the quantum dot and the electron conductor. The bifunctional ligand molecule may include an electron conductor anchor that bonds to the electron conductor and a first quantum dot anchor that bonds to the quantum dot. A hole conductor such as a conductive polymer may include a second quantum dot anchor. In some instances, the first quantum dot may include selenium.

Abstract: A solar cell is disclosed that includes an electron conductor layer and a quantum dot layer. The quantum dot layer may include a plurality of quantum dots. A bridge layer may be coupled to the electron conductor layer and to the quantum dot layer. The bridge layer may include an antibiotic, a sulfur-containing amino acid, a vitamin, and/or a vitamin analogue. In some cases, a hole conductor layer may be coupled to the quantum dot layer.

Abstract: A solar cell may include a quantum dot and an electron conductor. A bifunctional ligand may be disposed between the quantum dot and the electron conductor. The ligand molecule may include an electron conductor anchor that bonds to the electron conductor and a first quantum dot anchor that bonds to the quantum dot. A hole conductor such as a conductive polymer may include a second quantum dot anchor.

Abstract: A method includes forming a hole in a first wafer and forming a sensor structure in or on a second wafer. The second wafer includes a piezoelectric material. The method also includes bonding the first wafer and the second wafer, where the sensor structure is located between the wafers. The method further includes forming a sensing layer by depositing material between the wafers through the hole in the first wafer. The sensing layer could be formed by depositing a sensing layer material on the second wafer using direct printing. Also, the hole through the first wafer could be formed using ultrasonic milling, micro-drilling, laser drilling, wet etching, and/or plasma etching. A spacer material could be used to bond the wafers together, such as frit glass paste or an organic adhesive. Trenches could be formed in the first wafer to facilitate easier separation of multiple sensors.

Abstract: A sensor includes a piezoelectric substrate and conductive elements formed in or over the substrate. The sensor also includes a sensing layer formed over the substrate. The sensing layer has one or more properties (such as a mass loading, an electrical property, or a visco-elastic property) that vary based on at least one measurand to be measured by the sensor (such as carbon dioxide). This may affect, for example, a propagation velocity of acoustic waves in the sensor and/or a resonant frequency of the sensor. The sensing layer includes a combination of polyaniline and carbonic anhydrase. The combination of polyaniline and carbonic anhydrase could be formed using an emeraldine base. For instance, an aniline can be dissolved in water to form a mixture, and hydrochloric acid and an oxidant can be added to the mixture. A chemical polymerization of the aniline in the mixture can be performed to form polyanilne.

Abstract: A solar cell may include a light sensitive molecule such as a hyperpolarizable molecule. In one example, a solar cell may include a layer of hyperpolarizable molecules disposed between a p-type electrode and an n-type electrode. In some cases, at least some of the hyperpolarizable molecules may include an electron donating group that is bonded or otherwise linked to the n-type electrode as well as an electron accepting group that is bonded or otherwise linked to the p-type electrode. In some instances, at least some of the hyperpolarizable molecules may include an electron donating group that is bonded or otherwise linked to the p-type electrode as well as an electron accepting group that is bonded or otherwise linked to the n-type electrode.

Abstract: The design and synthesis of a matrix nanocomposite containing amino carbon nanotubes used as a functionalized sensing layer for carbon dioxide detection by means acoustic wave sensing devices, e.g., SAW/BAW devices. These sensing materials contain a type of amino carbon nanotubes (single walled or multi-walled) and a polymer (or other compounds) which are sensitive to carbon dioxide in the acoustic wave sensing device based gas sensors. The sensitivity of the matrix consisting of the amino carbon nanotubes and a polymer (or other compounds) is ensured by the presence of amino groups which can react at room temperature with CO2 in a reversible process to form carbamates.

Abstract: The design and deposition of a sensing layer for room temperature SAW/BAW chemical sensors utilizing macrocyclic compounds in accordance with supra-molecular chemistry principles. The gas to be sensed is attached to the organic sensing film thus changing its visco-elastic properties and creating a mass increase of the film deposited on the surface of SAW/BAW devices. A direct printing method can be used as an additive, mask-less procedure to deposit metallic interdigital transducers and electrodes required for SAW/BAW devices, along with the deposition of a guiding layer and the organic films only on the location required by the sensing SAW/BAW principle of the sensor. Different thermal treatment solutions can be used for the consolidation of the gelly organic films deposited by the direct printing methods.

Abstract: A piezoresistive pressure and/or strain sensor micro-machined primarily from plastic and/or glass. In one illustrative embodiment, the piezoresistive pressure sensor is formed on a polymer substrate. A first selectively implanted region is provided in the polymer substrate to create a piezoresistive region in the polymer substrate. A second selectively implanted region is then provided in at least part of the first selectively implanted region to modulate the electrical conductivity of the first selectively implanted region. The illustrative sensor may be selectively implanted with, for example, nitrogen to create the piezoresistive region, and boron to modulate the electrical conductivity of the piezoresistive region. Phosphorus or any other suitable material may also be used to modulate the electrical conductivity of the piezoresistive region, as desired.

Abstract: A pressure sensor is constructed of a plastic package. The plastic package incorporates in the same material a sensing diaphragm including tensile and compression regions. Deposited on the diaphragm are metal electrodes and a polymer film having piezoresistive properties. The electrodes and/or the polymer film are directly printed onto the plastic package without the use of a mask.