- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Benzo[ghi]perylene & Coronene as Ratiometric Reversible Optical Oxygen Nano-Sensor
摘要： The development of novel single molecular probe based optical ratiometric oxygen sensor with simple fabrication, high sensitivity, and linear response is highly desirable. Herein, benzo[ghi]perylene (BzP) and coronene (Cron) were explored as dual-emissive ratiometric oxygen nano-sensor that displayed linear plots at a low probe concentration (6 μM). The sensor fabrication was simple, and the probes exhibited efficient fluorescence quenching of monomer emission by molecular oxygen. However, the excimer emission of probe remained unaffected. Thus a ratiometric method is developed based on the dual emitting luminophore. The method can be used to estimate dissolved oxygen in liquids and 5 – 100 % of oxygen concentration in gaseous mixtures.
关键词： Coronene,Benzo[ghi]perylene,Oxygen sensing,Excimer emission,Ratiometric sensor,Fluorescence probe
更新于2025-11-14 17:04:02
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Multi-arm polymers prepared by atom transfer radical polymerization (ATRP) and their electrospun films as oxygen sensors and pressure sensitive paints
摘要： New oxygen and pressure sensitive paints (PSPs) with four-arm polymeric structures were prepared by using a kind of controlled living polymerizations - atom transfer radical polymerization (ATRP). The polymers composing of poly(isobutyl methacrylate)-co-poly(trifluoroethyl methacrylate)s (PolyIBMA-co-PolyTFEM)s act as the matrices for the platinum porphyrin-based phosphorescence probes, which were copolymerized in the matrices. The polymers were characterized by using 1H-NMR, 19F-NMR, and GPC to demonstrate their successful preparation. The influence of polymer structures on sensing activity including the sensitivity and response time to oxygen and/or pressure was investigated. Results showed that copolymers with suitable compositions (herein P3) can have highest sensitivity. Polymer structure's influence on response time to oxygen was also investigated. For increasing the polymer's surface area for further improving sensing sensitivity, electrospinning method was used for preparing films with micro-spherical or fibrous structures. The morphologies of electrospinning coated films were observed by SEM. Results showed that electrospinning coated films can respond much better to oxygen and pressure than their corresponding sprayed plates. This is the first time to apply the controlled living polymerization approach to prepare PSPs with multi-arm structures, which will broaden the PSP functional materials' design strategy.
关键词： oxygen sensing,pressure sensitive paints,electrospinning,multi-arm polymers,atom transfer radical polymerization
更新于2025-09-23 15:23:52
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Wearable, Luminescent Oxygen Sensor for Transcutaneous Oxygen Monitoring
摘要： We present a new concept for a wearable oxygen (O2) sensor for transcutaneous O2 pressure (tcpO2) monitoring by combining the technologies of luminescent gas sensing and wearable devices. O2 monitoring has been exhaustively studied given its central role in diagnosing various diseases. The ability to quantify the physiological distribution and real-time dynamics of O2 from subcellular to the macroscopic level is required to fully understand mechanisms associated with both normal physiological and pathological conditions. Despite its profound biological and clinical importance, few effective methods exist for noninvasively quantifying O2 in a physiological setting. The wearable sensor developed here consists of three components: a luminescent sensing film attached onto skin by a carbon tape, an organic light-emitting diode (OLED) as a light source, and an organic photodiode (OPD) as a light detector. All the components are solution-processable and integrated on a plane in a bandage-like configuration. To verify the performance, tcpO2 variations by pressure-induced occlusion were measured in the lower arm and a thumb by the wearable sensor, and the results were comparable to those measured by a commercial instrument. In addition to its flexibility, other features of this sensor render it a potential low-cost solution for the simultaneous monitoring of tcpO2 in any part of a body.
关键词： organic light-emitting diodes,transcutaneous oxygen monitoring,wearable sensors,luminescent oxygen sensing,organic photodiodes
更新于2025-09-23 15:21:21
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Controlled sol–gel synthesis of oxygen sensing CdO?:?ZnO hexagonal particles for different annealing temperatures
摘要： CdO : ZnO hexagonal particles were synthesized by a sol–gel precipitation method at di?erent annealing temperatures. A mixed crystal phase of cubic and wurtzite structures was observed from X-ray di?raction patterns. The micrographs showed hexagonal shapes of the CdO : ZnO nanocomposites particles. The energy dispersive X-ray spectroscopy mapping images showed a uniform distribution of the Cd and Zn. The CdO : ZnO nanocomposite pallet annealed at 550 (cid:1)C has an electrical resistance of 0.366 kU at room temperature. The nanocomposites showed an excellent sensing response against oxygen gas with a sensing response of 47% at 200 (cid:1)C for the CdO : ZnO particles annealed at 550 (cid:1)C. The sensor response and recovery times were found to be 43s and 45s, respectively. The sensor response was due to the sorption of oxygen ions on the surfaces of the CdO : ZnO hexagonal particles.
关键词： sol–gel,annealing temperature,hexagonal particles,oxygen sensing,CdO : ZnO
更新于2025-09-16 10:30:52
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Low Energy Pulsed Laser Excitation in UV Enhances the Gas Sensing Capacity of Photoluminescent ZnO Nanohybrids
摘要： Nanohybrids, composed of luminescent zinc oxide (ZnO) nanoparticles dispersed in an inert polydimethylsiloxane (PDMS) matrix, exhibit an excellent ability to follow changes in the type and composition of their surrounding atmosphere. These changes are found to affect the UV photoluminescence (PL) emission of the ZnO-PDMS hybrids measured at room temperature. The influence of irradiation parameters, such as excitation intensity and wavelength, on the response of the ZnO-PDMS sensor against ethanol and oxygen, have been systematically investigated in a comparative study performed employing pulsed excitation at 248 and 355 nm. This study represents the first demonstration that the sensing performance of the PL-based ZnO sensors can be optimized by tuning the excitation parameters and it particularly illustrates that maintaining a low pump energy density is crucial for enhancing the sensitivity of the sensor achieving response values approaching 100%.
关键词： ZnO photoluminescence,ethanol sensing,optical sensor,ZnO nanoparticles,gas sensing,oxygen sensing,ZnO-PDMS nanocomposite
更新于2025-09-12 10:27:22
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Photostability of oxygen-sensitive core-shell nanofibers
摘要： Core-shell electrospun nanofibers constitute a vehicle enabling novel uses for phosphorescent oxygen-sensitive molecules. In this work, we investigate compositional parameters and other factors governing fiber design appropriate to long-term sensor applications. These nanofibers contain an oxygen-sensitive palladium (II) porphyrin species within a polysulfone core; an outer polycaprolactone shell protects the core from the surrounding environment. The presence of a core-shell architecture was confirmed using advanced time-of-flight secondary ion mass spectrometry (ToF-SIMS). Although these sensors exhibit excellent photostability in the short-term, long-term exposures (up to 1,000 hr) are shown to detrimentally impact performance via photobleaching phenomenon. We also investigated higher porphyrin concentrations to determine whether the resulting sensors are predisposed to photobleaching. High porphyrin loadings (up to 10 wt%) could be successfully incorporated into the core. While increased probe content should logically enhance emission intensity, we sought to investigate the balance between a stronger signal and the potential for decreased photostability. The resulting behavior is rationalized by (1) establishing the spacing associated with a ‘perfect’ molecular dispersion and (2) invoking five distinct populations of porphyrin agglomeration. Populations that are not molecularly dispersed experience varying degrees of agglomeration-catalyzed photobleaching. The photobleaching rate increases with the extent of agglomeration and, therefore, the initial porphyrin content. Although it is demonstrated that low porphyrin loadings exhibit improved photobleaching resistance, the initial brightness is inadequate. In contrast, enhanced brightness via increased porphyrin content also leads to diminishing returns due to the apparent emergence of a self-quenched population. For a given application, selection of an appropriate porphyrin concentration is critical to achieving a compromise between initial brightness and photobleaching resistance. Detector sensitivity and anticipated duration of use must be considered when weighing the relative benefits of these attributes and selecting a specific porphyrin content.
关键词： Core-shell electrospinning,electrospun nanofiber,agglomeration,porphyrin,oxygen sensing
更新于2025-09-09 09:28:46
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Life sensors: current advances in oxygen sensing by lanthanide complexes
摘要： Aerobes, such as animals, plants, fungi, and several bacteria, depend upon oxygen to live. Consequently, oxygen sensing comprises an emerging technique in many research fields, ranging from medicine to marine science. In the last few years, lanthanide-based oxygen sensors have seen significant progress in the field of optical sensing technology owing to their long luminescence lifetimes and sharp luminescence bands. These sensors provide an alternative to expensive transition metal-based sensors, such as platinum and ruthenium complexes. This review covers the development and design of lanthanide-based oxygen sensors, along with their photophysical properties related to oxygen sensing. These lanthanide complexes achieve oxygen sensing through the excited state quenching of the intermediate triplet state of the antenna chromophore, which suggests that the sensitivity to pO2 arises from the rate of forward intramolecular energy transfer from the antenna triplet state to the accepting Ln3+ ion being competitive with bimolecular quenching by oxygen. As Tb(III) complexes are highly oxygen sensitive, they are favored to be good oxygen sensors, while the sensitivity of Eu(III), Dy(III), Nd(III), and Gd(III) complexes is low.
关键词： oxygen sensing,lanthanide complexes,Tb(III) complexes,optical sensing technology,photophysical properties
更新于2025-09-04 15:30:14