Highly selective nanostructure sensors and methods of detecting target analytes
Inventors
Motayed, Abhishek • Aluri, Geetha • Davydov, Albert V. • Rao, Mulpuri V. • Oleshko, Vladimir P. • Bajpai, Ritu • Zaghloul, Mona E. • Thomson, Brian • Wen, Baomei • Xie, Ting • Liu, Guannan • Debnath, Ratan
Assignees
George Washington University • George Mason University • University of Maryland College Park • United States Department of Commerce
Publication Number
US-9983183-B2
Publication Date
2018-05-29
Expiration Date
2033-04-12
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Abstract
A nanostructure sensing device comprises a semiconductor nanostructure having an outer surface, and at least one of metal or metal-oxide nanoparticle clusters functionalizing the outer surface of the nanostructure and forming a photoconductive nanostructure/nanocluster hybrid sensor enabling light-assisted sensing of a target analyte.
Core Innovation
The invention provides a nanostructure sensing device comprising a semiconductor nanostructure having an outer surface functionalized with at least one of metal or metal-oxide nanoparticle clusters. This forms a photoconductive nanostructure/nanocluster hybrid sensor enabling light-assisted sensing of a target analyte. The sensor operates at room temperature via photoenabled sensing and utilizes standard microfabrication techniques to achieve economical, multianalyte single-chip sensors with high sensitivity and selectivity.
The problem solved by this invention arises from the deficiencies of conventional metal-oxide based thin film sensors, which lack selectivity for different chemical species and typically require high working temperatures above 250° C. Existing devices show poor selectivity, require high temperatures and long response times, and often do not operate effectively in air, limiting their practical real-life applicability and commercial viability. There is a need for sensors capable of distinguishing individual analytes within chemical classes, operate at room temperature with fast response and recovery times, and provide reliable detection in various carrier gases including air.
The invention achieves this by functionalizing relatively inactive semiconductor nanostructure surfaces with selected analyte-dependent active metal-oxide and/or metal nanoparticles forming nanoclusters that provide tailored adsorption profiles. The hybrid devices combine the nanostructure backbone with photocatalytic nanoclusters, allowing light-assisted chemical sensing well below conventional operating temperatures, including room temperature. The sensors demonstrate excellent selectivity among aromatic compounds, volatile organic compounds, gases, and chemical warfare agents, with response and recovery times less than about 180 seconds. The design enables multi-component nanocluster architectures that suppress interfering adsorption, thereby enhancing selectivity.
Claims Coverage
The patent contains one independent claim introducing inventive features related to a multi-analyte sensor comprising a semiconductor nanostructure functionalized with two distinct nanoparticle types with differing adsorption profiles.
Multi-analyte nanostructure sensor with dual nanoparticle functionalization
A sensor comprising a semiconductor nanostructure with an outer surface functionalized by first metal-oxide nanoparticles having a first adsorption profile, and second nanoparticles of metal or metal-oxide having a second distinct adsorption profile; the sensor design enables a target analyte to preferentially adsorb on one nanoparticle type and an interfering analyte on the other, facilitating selective detection.
Photoactivated output change upon analyte detection
The sensor exhibits a measurable change in output current, voltage, or resistance upon detection of the target analyte.
Semiconductor nanostructure material composition
The semiconductor nanostructure is selected from gallium nitride (GaN), indium nitride (InN), aluminum gallium nitride (ALGaN), zinc oxide (ZnO), and indium arsenide (InAs).
Extensive nanoparticle selection for tailored adsorption
The first and second nanoparticles include a wide range of metal-oxide nanoparticles such as TiO2, SnO2, ZnO, NiO, and others, or metal nanoparticles including lithium, sodium, potassium, platinum, gold, and their alloys, allowing customization of adsorption properties.
Operation at low and room temperature
The sensor operates and can detect analytes at temperatures less than about 100° C., including room temperature (18° C. to 24° C.).
Detection of various analyte types
The sensor detects gases such as NOx, H2, CH4, CO2, CO, NH3, O2, SOx, H2S, Cl2, HCN, volatile organic compounds including benzene and toluene, chemical warfare agents, and simulant chemicals.
Integration with substrate and microheater capabilities
The sensor comprises the semiconductor nanostructure disposed on a substrate surface with an optional microheater to stabilize conditions of variable humidity or temperature, and may include temperature and humidity sensing elements.
Sensitive and fast response nanostructure sensor
The sensor can detect target analytes at concentrations between about 50 parts per billion and 1 percent, with response and recovery times less than about 180 seconds.
The claims broadly cover a multi-analyte nanostructure-based sensor functionalized with distinct metal-oxide and/or metal nanoparticle clusters enabling selective, photoactivated detection of target analytes at room temperature or below, incorporating various materials and structural configurations suited for fast, sensitive, and low-power operation.
Stated Advantages
Operates at room temperature enabled by light-assisted sensing resulting in low-power consumption, longer lifetime, and fast response/recovery times.
Excellent selectivity capable of discriminating between chemically similar compounds such as aromatic compounds and explosives.
Wide sensing concentration range from 50 parts per billion to 1 percent.
Rapid and reliable sensing with response and recovery times less than about 180 seconds, often around 75 seconds.
Capability for stable and repeatable operation in various carrier gases including air.
Compatibility with standard microfabrication techniques enabling mass production and economical multi-analyte single-chip sensors.
Documented Applications
Environmental monitoring of chemical species such as industrial pollutants, poisonous gases, chemical fumes, and volatile organic compounds (VOCs).
Hazmat and first responder detection of hazardous chemicals and rapid disaster chemical hazard identification.
Industrial monitoring and leak detection in production facilities, oil refineries, and manufacturing plants.
Law enforcement applications including breath analyzers for alcohol detection and personal alcohol monitoring.
Defense and security applications such as detection of explosives and chemical warfare agents, safety monitoring in public places and transit systems, and soldier carried or worn sensing equipment.
Indoor air quality monitoring for building ventilation control and detection of harmful VOCs and gases like CO.
Interested in licensing this patent?