摘要:
A sensor for selectively determining the presence and measuring the amount of hydrogen in the vicinity of the sensor. The sensor comprises a MEMS device coated with a nanostructured thin film of indium oxide doped tin oxide with an over layer of nanostructured barium cerate with platinum catalyst nanoparticles. Initial exposure to a UV light source, at room temperature, causes burning of organic residues present on the sensor surface and provides a clean surface for sensing hydrogen at room temperature. A giant room temperature hydrogen sensitivity is observed after making the UV source off. The hydrogen sensor of the invention can be usefully employed for the detection of hydrogen in an environment susceptible to the incursion or generation of hydrogen and may be conveniently used at room temperature.
摘要:
A gas sensor is disclosed, which includes two separate metal electrodes on a surface of a substrate and a semiconductor thin film deposited on the surface of the substrate and connecting the two metal electrodes. The semiconductor thin film contains zinc oxide or a mixed oxide of zinc and indium, and the zinc oxide or the mixed oxide of zinc and indium are in the form of nanowires which constitute a gas-sensing surface of the semiconductor thin film. The nanowires have a diameter of 50-900 nm. The present invention also discloses a method for detecting the presence of a NOx gas.
摘要:
Resistive-sensors are provided wherein networks or nanoframeworks of conducting polymer nanowires are electrochemically grown from pre-polymer solutions in the junction gap located between electrode pairs.
摘要:
The present invention relates to the use of a nanoparticle film having metal ions incorporated wherein and to a method of detecting a gaseous or volatile or liquid analyte in a medium.
摘要:
This invention relates generally to gas sensors comprising organized assemblies of carbon and non-carbon compounds. The invention also relates to devices containing such gas sensors and analysis units. In preferred embodiments, the organized assemblies of the instant invention take the form of nanorods or their aggregate forms. More preferably, a nanorod is made up of a carbon nanotube filled, coated, or both filled and coated by a non-carbon material.
摘要:
A nanorod sensor with a single plane of horizontally-aligned electrodes and an associated fabrication method are provided. The method provides a substrate and forms an intermediate electrode overlying a center region of the substrate. The intermediate electrode is a patterned bottom noble metal/Pt/Ti multilayered stack. TiO2 nanorods are formed over the substrate and intermediate electrode, and a TiO2 film may be formed overlying the TiO2 nanorods. The TiO2 nanorods and TiO2 film are formed in-situ, in the same process, by varying the substrate temperature. In other aspects, the TiO2 film is formed between the nanorods and the intermediate electrode. In yet another aspect, the TiO2 film is formed both above and below the nanorods. A single plane of top electrodes is formed overlying the TiO2 film from a top noble metal/Pt/Ti multilayered stack overlying the TiO2 film, which has been selectively etched to form separate top electrodes.
摘要:
A method of fabricating a stacked nanostructure array includes preparing a substrate; forming a bottom electrode directly on the substrate; growing a first nanostructure array directly on the bottom electrode; forming an insulating layer on the first nanostructure array; exposing the upper surface of the first nanostructure array; depositing a second, and subsequent, nanostructure array on a nanostructure array immediately below the second and subsequent nanostructure array; repeating said forming, said exposing and said depositing a subsequent steps to form a stacked nanostructure array; removing an uppermost insulating layer; and forming a top electrode on an uppermost nanostructure array. A sensor incorporating the nanostructure array includes top and bottom electrodes with plural layers of nanostructure array therebetween.
摘要:
Methods for the preparation of long, dimensionally uniform, metallic nanowires that are removable from the surface on which they are synthesized. The methods include the selective electrodeposition of metal nanowires at step edges present on a stepped surface, such as graphite, from an aqueous solution containing a metal or metal oxide. Where a metal oxide is first deposited, the metal oxide nanowires are reduced via a gas phase reduction at elevated temperatures to metal nanowires. Alternatively, beaded or hybrid nanowires comprising a metal A into which nanoparticles of a metal B have been inserted may be prepared by first electrodepositing nanoparticles of metal B selectively along step edges of a stepped surface, capping these nanoparticles with a molecular layer of an organic ligand, selectively electrodepositing nanowire segments of metal A between nanoparticles of metal B and then heating the surface of the hybrid nanowire under reducing conditions to remove the ligand layer. In all three methods, the nanowires may be removed from the stepped surface by embedding the wires in a polymer film, and then peeling this film containing the embedded wires off of the stepped surface.
摘要:
A gas sensor utilizes nano-sized CeO2 and doped CeO2 particles for detecting NO, NO2 and also for studying the cross sensitivity of oxygen, un-burnt hydrocarbons, CO and CO2. Nano-crystalline powders of CeO2 and doped CeO2 are employed to configure thin films on Platinum comb type electrodes preformed on alumina substrates. Various catalytic oxides are employed to convert the NO to NO2 to get equal response to NOx gas. Gas sensing properties are measured using a dynamic chamber with a constant flow of air and NOX gas in required percentage in nitrogen gas.
摘要翻译:气体传感器利用纳米尺度的CeO 2和掺杂的CeO 2 N 2颗粒来检测NO,NO 2,并且还用于研究氧,未燃烧的烃,CO和 CO 2 SUB>。 使用CeO 2 N 2和掺杂的CeO 2 2的纳米结晶粉末来构造在氧化铝基底上预制的铂梳型电极上的薄膜。 使用各种催化氧化物将NO转化为NO 2以获得对NOx气体的相等响应。 使用具有恒定空气流量和氮气中所需百分比的NOX气体的动态室来测量气体感测特性。
摘要:
Polymer nanofibers, such as polyaniline nanofibers, with uniform diameters less than 500 nm can be made in bulk quantities through a facile aqueous and organic interfacial polymerization method at ambient conditions. The nanofibers have lengths varying from 500 nm to 10 μm and form interconnected networks in a thin film. Thin film nanofiber sensors can be made of the polyaniline nanofibers having superior performance in both sensitivity and time response to a variety of gas vapors including, acids, bases, redox active vapors, alcohols and volatile organic chemicals.