Abstract: The invention disclosed herein generally contemplates novel microelectrodes and methods of preparing same.

Abstract: Provided is a system for continuous generation of gases, the system including an electrochemical device and an active- material regeneration device.

Abstract: Provided are electrochemical cells and methods for generating hydrogen gas and oxygen gas.

Abstract: Provided are electrochemical cells and methods for generating hydrogen gas and oxygen gas.

Abstract: A system and method for generating hydrogen gas from an aqueous solution are disclosed herein. The system comprises a compartment with a working electrode for reducing water in response to an applied voltage to generate hydrogen and a redox-active electrode capable of reversibly undergoing oxidation and reduction. The system may further comprise a second compartment with a working electrode for generating oxygen and redox-active electrode electrically connectable to the redox-active electrode in the first compartment. The method comprises applying a voltage between a working electrode and a redox-active electrode of a system described herein and/or between comprising a working electrode of one compartment and a working electrode of a second compartment of a system described herein.

Abstract: Provided are electrochemical cells and methods for generating hydrogen gas and oxygen gas.

Abstract: A system and method for generating hydrogen gas from an aqueous solution are disclosed herein. The system comprises a compartment with a working electrode for reducing water in response to an applied voltage to generate hydrogen and a redox-active electrode capable of reversibly undergoing oxidation and reduction. The system may further comprise a second compartment with a working electrode for generating oxygen and redox-active electrode electrically connectable to the redox-active electrode in the first compartment. The method comprises applying a voltage between a working electrode and a redox-active electrode of a system described herein and/or between comprising a working electrode of one compartment and a working electrode of a second compartment of a system described herein.

Abstract: A system and method for generating hydrogen gas from an aqueous solution are disclosed herein. The system comprises a compartment with a working electrode for reducing water in response to an applied voltage to generate hydrogen and a redox-active electrode capable of reversibly undergoing oxidation and reduction. The system may further comprise a second compartment with a working electrode for generating oxygen and redox-active electrode electrically connectable to the redox-active electrode in the first compartment. The method comprises applying a voltage between a working electrode and a redox-active electrode of a system described herein and/or between comprising a working electrode of one compartment and a working electrode of a second compartment of a system described herein.

Abstract: This disclosure provides systems, methods, and apparatus related to a hybrid photo-electrochemical and photo-voltaic cell. In one aspect, device includes a substrate comprising a semiconductor, a transparent conductor disposed on the second surface of the substrate, a photoanode disposed on the transparent conductor, an electrolyte in electrical communication with the photoanode, and an electrode in contact with the electrolyte. The substrate is doped with a first n-type dopant. A first area of a first surface of the substrate is heavily doped with a first p-type dopant. A second area of the first surface of the substrate is heavily doped with a second n-type dopant. The second surface of the substrate is heavily doped with a second p-type dopant. The electrode is in electrical contact with the second area. The first area is in electrical contact with the second area through an electrical load.

Abstract: This disclosure provides systems, methods, and apparatus related to a hybrid photo-electrochemical and photo-voltaic cell. In one aspect, device includes a substrate comprising a semiconductor, a transparent conductor disposed on the second surface of the substrate, a photoanode disposed on the transparent conductor, an electrolyte in electrical communication with the photoanode, and an electrode in contact with the electrolyte. The substrate is doped with a first n-type dopant. A first area of a first surface of the substrate is heavily doped with a first p-type dopant. A second area of the first surface of the substrate is heavily doped with a second n-type dopant. The second surface of the substrate is heavily doped with a second p-type dopant. The electrode is in electrical contact with the second area. The first area is in electrical contact with the second area through an electrical load.

Abstract: A system and method for generating hydrogen gas from an aqueous solution are disclosed herein. The system comprises a compartment with a working electrode for reducing water in response to an applied voltage to generate hydrogen and a redox-active electrode capable of reversibly undergoing oxidation and reduction. The system may further comprise a second compartment with a working electrode for generating oxygen and redox-active electrode electrically connectable to the redox-active electrode in the first compartment. The method comprises applying a voltage between a working electrode and a redox-active electrode of a system described herein and/or between comprising a working electrode of one compartment and a working electrode of a second compartment of a system described herein.

Abstract: A memory cell (32C), including a first non-insulator (34C) and a second non-insulator (40C), different from the first non-insulator. The second non-insulator forms a junction (46C) with the first non-insulator. The cell further includes a first electrode (48C) which is connected to the first non-insulator and a second electrode (50C) which is connected to the second non-insulator. At least one of the first and second non-insulators is chosen from a group consisting of a solid electrolyte and a mixed ionic electronic conductor and has an ionic transference number less than 1 and greater than or equal to 0.5.

Abstract: A memory cell (32C), including a first non-insulator (34C) and a second non-insulator (40C), different from the first non-insulator. The second non-insulator forms a junction (46C) with the first non-insulator. The cell further includes a first electrode (48C) which is connected to the first non-insulator and a second electrode (50C) which is connected to the second non-insulator. At least one of the first and second non-insulators is chosen from a group consisting of a solid electrolyte and a mixed ionic electronic conductor and has an ionic transference number less than 1 and greater than or equal to 0.5.

Abstract: A sensor array is provided including a plurality of fibers being woven to form 3-D periodic fiber structures. A selective number of the fibers include gaseous sensing materials to detect selective gases. A plurality of spacing elements provides adequate spacing between successively arranged nano-fibers. The nano-fibers and spacing elements are arranged to form a 3-D scaffolding structure for detecting specific or combinations of gaseous analytes.

Abstract: A method for fabricating an ultra-sensitive metal oxide gas sensor is disclosed, which comprises the steps of spinning a mixture solution including a metal oxide precursor and a polymer onto a sensor electrode to form a metal oxide precursor-polymer composite fiber; thermally compressing or thermally pressurizing the composite fiber; and thermally treating the thermally compressed or thermally pressurized composite fiber to remove the polymer from the composite fiber. Since the gas sensor includes a macro pore between nanofibers and a meso pore between nano-rods and/or nano-grains, gas diffusion and surface area can be maximized. Also, the ultra-sensitive sensor having high stability in view of mechanical, thermal, and electrical aspects can be obtained through rapid increase of adhesion between the metal oxide thin layer and the sensor electrode.

Abstract: A selective gas sensor comprises a semiconducting substrate, a radiation source that directs narrowband radiation to the semiconducting substrate; and a plurality of electrodes coupled to the semiconducting substrate, whereby a gas is selectively sensed. A method of selectively sensing a gas comprises the steps of contacting the semiconducting substrate with a gas, directing narrowband radiation to the semiconducting substrate and sensing the resistance of the semiconducting substrate, thereby selectively sensing the gas.

Abstract: A method for fabricating an ultra-sensitive metal oxide gas sensor is disclosed, which comprises the steps of spinning a mixture solution including a metal oxide precursor and a polymer onto a sensor electrode to form a metal oxide precursor-polymer composite fiber; thermally compressing or thermally pressurizing the composite fiber; and thermally treating the thermally compressed or thermally pressurized composite fiber to remove the polymer from the composite fiber. Since the gas sensor includes a macro pore between nanofibers and a meso pore between nano-rods and/or nano-grains, gas diffusion and surface area can be maximized. Also, the ultra-sensitive sensor having high stability in view of mechanical, thermal, and electrical aspects can be obtained through rapid increase of adhesion between the metal oxide thin layer and the sensor electrode.

Abstract: A selective gas sensor comprises a semiconducting substrate, a radiation source that directs narrowband radiation to the semiconducting substrate; and a plurality of electrodes coupled to the semiconducting substrate, whereby a gas is selectively sensed. A method of selectively sensing a gas comprises the steps of contacting the semiconducting substrate with a gas, directing narrowband radiation to the semiconducting substrate and sensing the resistance of the semiconducting substrate, thereby selectively sensing the gas.