- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
[IEEE 2018 IEEE SENSORS - New Delhi, India (2018.10.28-2018.10.31)] 2018 IEEE SENSORS - A Flexible Room Temperature Ammonia Sensor Based on Large Area, Transparent Single Wall Carbon Nanotube Thin Film
摘要： A low-temperature, wet-chemical process for the synthesis of single wall carbon nanotubes (SWCNTs) films on large area, transparent, flexible substrates were developed and its application to ammonia detection at room temperature were demonstrated. The carboxyl groups were attached in the sidewalls of carbon nanotubes due to wet-chemical process which helps to improve the sensor performance. The transmittance measurement showed that the film is ninety percent transparent to visible spectrum with respect to air. Selectivity measurements were also performed. The sensor responses were same for both the fat and bend film. The present SWCNTs based sensors could potentially be used to develop low cost, flexible, foldable and disposable sensor system for the monitoring of toxic gases like ammonia in environment.
关键词： functionalized SWCNTs,ammonia sensor,Flexible gas sensor,room temperature,gas sensor
更新于2025-09-23 15:22:29
-
Gas sensing performance of GaOOH and β-Ga<sub>2</sub>O<sub>3</sub> synthesized by Hydrothermal method: A comparison
摘要： Gallium Oxy Hydrate (GaOOH) and β-Ga2O3 nanostructures in submicron scale have been synthesized at low temperature by surfactant-free hydro-thermal method. First, GaOOH has been synthesized using Gallium nitrate anhydrate, Ammonium hydroxide as precursors and double distilled water as solvent. As obtained GaOOH powders have been characterized by XRD, FE–SEM, UV–VIS, Thermo Gravimetric Analysis, I-V characteristics and BET surface analysis in order to reveal their structural, morphological, optical, thermal, electrical and surface properties. FE-SEM micrographs confirm the rod like and needle like morphologies of GaOOH and β- Ga2O3 samples, respectively. Porous nature of the samples observed through BET and BJH analyses. Synthesized GaOOH and β-Ga2O3 powders have been subjected to room temperature CO2 gas sensing in the range, 2000 ppm – 10000 ppm. GaOOH showed quick response of 80 s and fast recovery of 129 s at 8000 ppm while β-Ga2O3 showed quick response of 52 s at 8000 ppm and faster recovery of 98 s at 4000 ppm. Also, the repeatability studies were done for GaOOH and β-Ga2O3 films by exposing to different CO2 concentrations for a period of 6 consecutive days. β-Ga2O3 showed enhanced CO2 sensing response than that of GaOOH due to its better structural, electrical, morphological and surface properties.
关键词： Gallium Oxide (Ga2O3),Gallium Oxide Hydroxide (GaOOH),Hydrothermal method,Characterization,Room temperature CO2 sensing
更新于2025-09-23 15:21:21
-
Magnetoencephalography with optically pumped 4He magnetometers at ambient temperature
摘要： In this paper, we present the first proof of concept confirming the possibility to record magnetoencephalographic (MEG) signals with Optically Pumped Magnetometers (OPMs) based on the parametric resonance of 4He atoms. The main advantage of this kind of OPM is the possibility to provide a tri-axis vector measurement of the magnetic field at room-temperature (the 4He vapor is neither cooled nor heated). The sensor achieves a sensitivity of 210 fT/√Hz in the bandwidth [2 Hz - 300 Hz]. MEG simulation studies with a brain phantom were cross-validated with real MEG measurements on a healthy subject. For both studies, MEG signal was recorded consecutively with OPMs and Superconducting Quantum Interference Devices (SQUIDs) used as reference sensors. For healthy subject MEG recordings, three MEG proofs of concept were carried out: auditory and visual evoked fields (AEF, VEF), and spontaneous activity. M100 peaks have been detected on evoked responses recorded by both OPMs and SQUIDs with no latency. Concerning spontaneous activity, an attenuation of the signal power between 8-12 Hz (alpha band) related to eyes opening has been observed with OPM similarly to SQUID. All these results confirm that the room temperature vector 4He OPMs can record MEG signals and provide reliable information on brain activity.
关键词： visual evoked field,Optically pumped magnetometer,vector measurement,magnetoencephalography,spontaneous activity,auditory evoked field,room temperature,Helium 4
更新于2025-09-23 15:21:21
-
[IEEE 2018 31st International Vacuum Nanoelectronics Conference (IVNC) - Kyoto, Japan (2018.7.9-2018.7.13)] 2018 31st International Vacuum Nanoelectronics Conference (IVNC) - Nanogranular Compound Material Layers Serve as Storage for Infra-red to Ultra-Violet Photons for the Energy Supply for Electric Machines
摘要： Hyper-Giant conducting nanogranular compound materials, which serve as IR photon detectors allow to use BOSON-current transport at room temperature with GA/cm2 current carrying capability for Energy applications
关键词： Room temperature,Bosons having parallel spin,Boson-current transport,Energy supply for electric machines
更新于2025-09-23 15:21:21
-
Room temperature synthesis of CdS/SrTiO3 nanodots-on-nanocubes for efficient photocatalytic H2 evolution from water
摘要： Spontaneous solar-driven water splitting to generate H2 with no pollution discharge is an ideal H2 generation approach. However, its ef?ciency remains far from real application owing to the poor light-harvesting and ultrafast charge recombination of photocatalysts. To address these issues, herein, we employed a novel but simple chemical bath deposition (CBD) method to construct CdS/SrTiO3 nanodots-on- nanocubes at room temperature (ca. 25 (cid:1)C). The as-synthesized nanohybrids not only expand light absorption from ultraviolet (UV) to visible light but also signi?cantly retard charge recombination owing to the well-de?ned heterostructure formation. As a result, the CdS/SrTiO3 exhibits high photocatalytic performance with H2 evolution rate of 1322 lmol g(cid:1)1 h(cid:1)1, which is 2.8 and 12.2 times higher than that of pristine CdS and SrTiO3, respectively. This work provides a universal approach for the heterostructure construction, and inspired by this, higher ef?cient photocatalysts for H2 evolution may be developed in the near future.
关键词： Nanoheterostructure,H2 generation,Room temperature,CdS/SrTiO3,Photocatalyst
更新于2025-09-23 15:21:21
-
Towards bright and pure single photon emitters at 300 K based on GaN quantum dots on silicon
摘要： Quantum dots (QDs) based on III-nitride semiconductors are promising for single photon emission at non-cryogenic temperatures due to their large exciton binding energies. Here, we demonstrate GaN QD single photon emitters operating at 300 K with g(2)(0) = 0.17 ± 0.08. At this temperature, single photon emission rates up to 106 s?1 are reached while g(2)(0) ≤ 0.5 is maintained. Our results are achieved for GaN QDs embedded in a planar AlN layer grown on silicon, representing a promising pathway for future interlinkage with optical waveguides and cavities. These samples allow exploring the limiting factors to key performance metrics for single photon sources, such as brightness and single photon purity. While high brightness is assured by large exciton binding energies, the single photon purity is mainly affected by the spectral overlap with the biexcitonic emission. Thus, the performance of a GaN QD as a single photon emitter depends on the balance between the emission linewidth and the biexciton binding energy. Small GaN QDs with an emission energy in excess of 4.2 eV are promising candidates for future room temperature applications, since the biexciton binding energy becomes comparable to the average emission linewidth of around 55 meV.
关键词： single photon source,GaN,room temperature,wide bandgap,quantum dot
更新于2025-09-23 15:21:01
-
Ultralong Lifetime Room Temperature Phosphorescence and Dual-band Waveguide Behavior of Phosphoramidic Acid Oligomers
摘要： In recent years, some natural or synthetic non-conjugated luminescence systems have attracted much attention. However, the phosphorescent properties of these materials are generally not very satisfactory due to the lack of special molecular design. In this work, the phosphoramidic acid is introduced into the oligomer matrix to construct a non-conjugated photoluminescence system with ultralong phosphorescence lifetime up to 376.5 to 776.9 ms and high phosphorescence quantum yield (4.6-10.5 %). At the same time, the new system also displays good thermo-processing properties, vitreous solid and optical waveguide behavior.
关键词： Room temperature phosphorescence,ultralong phosphorescence lifetime,phosphoramidic acid oligomers,optical waveguide behavior
更新于2025-09-23 15:21:01
-
Circularly Polarized Rooma??Temperature Phosphorescence and Encapsulation Engineering for MOFa??Based Fluorescent/Phosphorescent WLEDs
摘要： Optical materials with circularly polarized luminescence and room temperature phosphorescence currently attract great attention owing to their unique optoelectronic properties. Herein, via the coordination-induced assembly strategy, a homochiral metal–organic framework (MOF) 1 with high stability and porosity is successfully synthesized by using the achiral triphenylamine-based molecule as the building block. Remarkably, MOF 1 shows circularly polarized luminescence and phosphorescence at room temperature simultaneously, also with excellent anisotropic optical properties. Furthermore, MOF 1 can serve as a nanocontainer to construct dye-encapsulated host–guest systems. Importantly, the multicolor emissions including white-light emission can be achieved. The corresponding color rendering index and correlated color temperature values of light emitting device are 73 and 5541 K, when using dye-loaded MOF 1?RhB 10 (CIE: 0.33, 0.33) as single-phase white light-emitting phosphor. This study first reports circularly polarized phosphorescence based on MOF without precious metals under ambient conditions, and also is first time for phosphorescent polarized materials with high porosity. These results will open up a new pathway to the design of porous chiroptical materials and white-light materials.
关键词： circularly polarized luminescence,host–guest system,room temperature phosphorescence,white light emitting devices,metal–organic frameworks
更新于2025-09-23 15:21:01
-
Ultrahigh-Speed Mid-Infrared Photodetectors With 2-D Electron Gas in a CdTe/PbTe Heterojunction
摘要： A CdTe/PbTe heterojunction (HJ) yields two-dimensional electron gas (2DEG) with a high electron density and mobility. Ultrahigh-speed and room-temperature operating mid-infrared photodetectors are developed with the 2DEG. The photoresponse of the detectors originates from the intrinsic response of PbTe by virtue of the conduction-band and valence-band alignment of the HJ. The extremely short rise and decay photoresponse time demonstrate a major advantage of the 2DEG. At λ = 3.0 μm and a bias voltage of 100 mV, the responsivity and detectivity reach 0.94 A/W and 2 × 1010 Jones, respectively. The excellent performance of the detectors renders promising applications in novel mid-infrared frequency detection systems.
关键词： two-dimensional electron gas (2DEG),room-temperature (RT) operation,ultrahigh-speed response,Detectivity,mid-infrared detector
更新于2025-09-23 15:21:01
-
Mid-infrared dual-comb spectroscopy with room-temperature bi-functional interband cascade lasers and detectors
摘要： Interband cascade (IC) laser structures offer attractive potential for operation at room temperature as both broadband coherent sources of mid-infrared light and fast photodetectors. This makes the realization of extremely compact spectrometers on a monolithic platform possible, and even dual-comb spectroscopy (DCS) configurations. IC comb devices are perfect candidates for this configuration, since they develop near-THz-wide optical frequency comb spectra from a millimeter-sized cavity, using a multi-stage structure that can also function as a very fast photodetector. In this work, we leverage IC photodetectors with a gigahertz bandwidth to demonstrate a self-contained, free-running, room-temperature DCS system in the mid-infrared. The DCS system used detection by the same bi-functional IC device structure to measure 1,1-difluoroethane over (cid:2)600 GHz of optical coverage around 3.6 mm. These results show that the IC platform is suitable for full integration as a broadband, high-resolution on-chip spectrometer in a future chemical sensing system.
关键词： mid-infrared,photodetectors,dual-comb spectroscopy,interband cascade lasers,room-temperature
更新于2025-09-23 15:21:01