The present inventive concept relates to a battery-free gas sensor or humidity sensor comprising a metal-organic framework and a method of manufacturing the same. In a photodiode-type battery-free gas sensor or humidity sensor according to the present inventive concept, since photoelectron collection electrodes are formed at certain intervals between P-N junction layers, when gas is adsorbed thereon, the gas can be detected without an extra power source by change of photocurrent. Due to fine pores of the metal-organic framework, gas sensitivity may be increased and stability of catalysts may be improved. When catalysts are not provided, humidity may be detected. Therefore, a system that used the photodiode-type battery-free gas sensor and the photodiode-type battery-free humidity sensor together may be performed humidity correction to accurately measure an amount of a gas.

A gas-concentration detector system incorporates a temperature sensor, a humidity sensor, and a gas-concentration detector the accuracy of which deviates as a function of temperature and humidity. Contemporaneous, real-time values of temperature, humidity, and gas concentration of a gas of interest are registered and communicated to a data processing system including a computer memory and a computer processor. Value-deviation data reflective of the degree to which the accuracy of the gas-concentration sensor deviates as a function of temperature and humidity are predetermined and stored in the computer memory. Provided with real-time gas-concentration, temperature, and humidity values, the computer processor executes a value-reconciling algorithm which, based on consultation with the stored value-deviation data, calculates and outputs a refined gas-concentration value more is accurately representative of the actual gas-concentration value within the selected environment in which gas-concentration detection and reporting is desired.

Disclosed herein is a system for detecting cancer cells. The system includes a biosensor comprising a graphene-Si Schottky junction, a light source placed above the biosensor, an electrical stimulator-analyzer connected to the biosensor, and a processing unit connected to the electrical stimulator-analyzer and the light source. The processing unit is configured to perform a method. The method includes generating a set of photocurrents in a reverse bias regime passed through the graphene-Si Schottky junction with a sample placed thereon utilizing the light source and the electrical stimulator-analyzer, measuring the set of the generated photocurrents through the graphene-semiconductor Schottky junction in reverse bias regime in the presence of the sample utilizing the electrical stimulator-analyzer device, and detecting a presence of cancer cells in the sample responsive to detecting a change in the measured set of the generated photocurrents within the reverse bias regime.

A method of identifying a gas is provided. The method includes providing a gas sensor device comprising at least two stacked metal oxide layers, wherein a change in conductance of the gas sensor device in a presence of a gas varies with a temperature of the stacked metal oxide layers. The method includes bringing the gas into proximity with the stacked metal oxide layers. The method also includes measuring the conductance of the gas sensor device when the gas is in proximity with the stacked layers at multiple temperatures to generate a temperature-conductance profile. The method also includes identifying a gas of interest based on the temperature-conductance profile.

Miniature resistive gas detectors incorporate thin films that can selectively identify specific gases when heated to certain characteristic temperatures. A solid state gas sensor module is disclosed that includes a gas sensor, a heater, and a temperature sensor, stacked over an insulating recess. The insulating recess is partially filled with a support material that provides structural integrity. The solid state gas sensor module can be integrated on top of an ASIC on a common substrate. With sufficient thermal insulation, such a gas detector can be provided as a low-power component of mobile electronic devices such as smart phones. A method of operating a multi-sensor array allows detection of relative concentrations of different gas species by either using dedicated sensors, or by thermally tuning the sensors to monitor different gas species.

A nanostructure device is provided and performs dual functions as a nano-switching/sensing device. The nanostructure device includes a doped semiconducting substrate, an insulating layer disposed on the doped semiconducting substrate, an electrode formed on the insulating layer, and at least one polymer nanofiber deposited on the electrode. The at least one polymer nanofiber provides an electrical connection between the electrode and the substrate and is the electroactive element in the device.

Disclosed are a hydrogen sensor which includes a P-type silicon nanowire array and a hydrogenation catalyst formed on a surface of the nanowire array, and a method of manufacturing the same.

Sensors and sensing methods are provided which can be highly sensitive but relatively inexpensive and small, which are suitable for uses such UAVs, distributed field monitors, medical diagnosis, and environmental monitoring. Various of these sensors can be characterized by one or more features which produce extreme insect antenna sensitivity and identification capability for chemical analytes.

An electric field variable gas sensor includes a semiconductor substrate, an insulating film disposed on the semiconductor substrate, a semiconductor thin film material disposed on a part of the semiconductor substrate and a part of the insulating film, a gas molecule adsorption inducing material disposed on the semiconductor thin film material, a first electrode disposed on the semiconductor substrate to be spaced apart from the semiconductor thin film material, and a second electrode disposed on the insulating film to be connected with the semiconductor thin film material.

A method of identifying a gas is provided. The method includes providing a gas sensor device comprising at least two stacked metal oxide layers, wherein a change in conductance of the gas sensor device in a presence of a gas varies with a temperature of the stacked metal oxide layers. The method includes bringing the gas into proximity with the stacked metal oxide layers. The method also includes measuring the conductance of the gas sensor device when the gas is in proximity with the stacked layers at multiple temperatures to generate a temperature-conductance profile. The method also includes identifying a gas of interest based on the temperature-conductance profile.