- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Optically Modulated Threshold Switching in Corea??Shell Quantum Dot Based Memristive Device
摘要： The threshold switching (TS) phenomenon in memristors has drawn great attention for its versatile applications in selectors, artificial neurons, true random number generators, and electronic integrations. The transition between nonvolatile resistive switching and volatile TS modes can be realized by doping, varying annealing and voltage sweeping conditions, or imposing different compliance current. Here, a strategy is reported to achieve such transition by the noninvasive UV light stimulus based on InP/ZnS quantum dot (QD) memristor. The core–shell InP/ZnS QDs with quasi-type II band alignment ensures photoexcited electrons localized in InP core, photoexcited hole state distributed in the outer shell, and subsequent lifetime controlling of conductive filament under light irradiation. Systematic mechanism investigations indicate that UV photogenerated holes are accumulated on the surface of the QD film, which is consistent with rapid transfer of photogenerated holes in the core–shell InP/ZnS structure. Based on the light-modulated effect, a reconfigurable 9 × 9 visual data storage array with a key pattern and a simple leaky integrate-and-fire circuit are constructed. These results suggest the potential of direct optical modulation of memory mode through energy band engineering, leading to future optoelectronic and electronic device for the implementation of neuromorphic visual system and artificial neural networks.
关键词： quantum dots,light modulation,volatile threshold switching
更新于2025-09-23 15:19:57
-
Configurable Multi-State Non-volatile Memory Behaviors in Ti <sub/>3</sub> C <sub/>2</sub> Nanosheets
摘要： MXenes have drawn considerable attention in both academia and industry due to the attracting properties such as the combination of metallic conductivity and surface hydrophilicity. However, to the best of our knowledge, the potential use of MXenes in non-volatile resistive random access memories (RRAMs) has rarely been reported. In this paper, we have firstly demonstrated the RRAM device with the MXene (Ti3C2) as the active component. The Ti3C2-based RRAM exhibits a typical bipolar switching behavior, long retention characteristic, low SET voltage, good mechanical stability and excellent reliability. By adjusting different compliance current in the SET process, the multi-state information storage could be achieved. The charge trapping assist hopping process is considered to be the main mechanism of resistive switching of this fabricated Ti3C2-based RRAM, which is verified by conductive atomic force microscopy (C-AFM) and Kelvin probe force microscopy (KPFM). Moreover, the flexible Ti3C2-based RRAM with good mechanical stability and long retention property could be successfully fabricated using on plastic substrate. Ti3C2-based RRAM may open the door to additional applications and functionalities with the highly potential application in flexible electronics.
关键词： MXenes,non-volatile memory,flexible electronics,resistive random access memory,Ti3C2,multi-state storage
更新于2025-09-19 17:15:36
-
[IEEE 2018 IEEE 13th Nanotechnology Materials and Devices Conference (NMDC) - Portland, OR, USA (2018.10.14-2018.10.17)] 2018 IEEE 13th Nanotechnology Materials and Devices Conference (NMDC) - An RRAM with a 2D Material Embedded Double Switching Layer for Neuromorphic Computing
摘要： Resistive random-access memory (RRAM) has shown great potential for neuromorphic engineering, due to its ability of emulating neural network and simple structure. To mimic the brain-learning behavior, two types of neural actions, short-term plasticity (STP) and long-term potentiation (LTP), should be imitated perfectly. In this work, we propose a unique RRAM cell with a double switching layer, in which a 2D material is embedded as a separation layer. Within a proper voltage range of stress, the mobile oxygen ions are blocked by the single atomic layer, and hence the subsequent relaxation of oxygen ions leads to a volatile switching characteristic. Owing to this volatile characteristic, the proposed device can mimic neural actions, STP and LTP, by a simple pulse train with different repetitions and frequencies without the complicated pulse settings of spike-timing-dependent plasticity (STDP). For various future brain-inspired applications, different switching materials with different bind energies and relaxation times of oxygen ions can be utilized.
关键词： LTP,2D materials,neuromorphic engineering,RRAM,STP,transition-metal-oxide,volatile
更新于2025-09-19 17:15:36
-
Artificial tailored catalytic activity for identification of 6 kinds of volatile organic compounds via the light-regulated electrochemical reaction
摘要： Light-regulated electrochemical reaction is confirmed to be useful to improve the classification efficiency. However, the use of different photoactive sensing materials results in time-consuming for exploring well-designed materials, besides, the light-regulated electrochemical reaction only improved the classification feature while didn't bring essential difference in the distinguish capability yet. Herein, a zirconia-based electrochemical sensor array comprised of 3 types of ZnO/In2O3 composite sensing materials is fabricated. After illumination, significantly enhancement is witnessed for the response magnitude and detection limit. Additionally, the response signal of the sensor array to part of the examined volatile organic compounds (VOCs) is selectively enhanced and 3 more disparate response patterns are generated. Through inputting all the response patterns into principle component analysis (PCA) software, 6 kinds of concerned VOCs have been fully classified. Conclusively, with utilizing sensing materials with similar composition, the fabrication process of the sensor array can be simplified. Particularly, after exposure to illumination the sensor array consisting of limited photoactive sensing materials (e.g. 3 kinds of materials) can identify even more number of gases (e.g. 6 types of VOCs). We anticipate these promising results shed light on the bright future of designing compact sensing devices for progressively smarter monitoring of concerned gas species.
关键词： Principle component analysis,Light-regulated electrochemical reaction,Volatile organic compounds,Response patterns,Artificial tailored catalytic activity,Zirconia-based sensor array
更新于2025-09-19 17:15:36
-
Development of an optoelectronic nose based on surface plasmon resonance imaging with peptide and hairpin DNA for sensing volatile organic compounds
摘要： Nowadays, the analysis of volatile organic compounds (VOCs) is very important in various domains. In the last decades, electronic noses have emerged as promising alternatives to traditional analytical methods. Nevertheless, their wide use is still limited by their performances such as low selectivity. Herein, we developed an optoelectronic nose using virtually screened peptides and hairpin DNA (hpDNA) with improved selectivity as sensing materials and surface plasmon resonance imaging (SPRi) as the detection system. Thanks to the complementarity of their binding properties towards target VOCs, the obtained optoelectronic nose has very good selectivity, being able to discriminate not only between VOCs of different chemical families, but also VOCs of the same family with only 1-carbon difference. The combination of these sensing materials with SPRi is relevant for the development of optoelectronic nose with large sensor arrays and improved performances.
关键词： Volatile organic compounds,Surface plasmon resonance imaging,E-nose,Peptides,Optoelectronic nose,Hairpin DNA
更新于2025-09-19 17:13:59
-
Photocatalytic degradation of gaseous toluene using self-assembled air filter based on chitosan/activated carbon/TiO2
摘要： Photocatalytic filters are integrated with air purifiers and ventilation systems to remove volatile organic compounds (VOCs) from indoor air. However, the filters, generally prepared by dip or spray coating, are less stable as the deposited TiO2 NPs are prone to be blown off by treated air. In the present study, we propose a novel filter preparation method based on self-assembly of activated carbon (AC) and TiO2 on non-woven polyethylene terephthalate (PET) fabric using chitosan (CS). The prepared filter (CSAT-PET) was characterized for morphological and chemical properties which revealed the homogeneity and chemical bonding of deposited TiO2. Photocatalytic activity of the prepared filter was evaluated for toluene degradation (200–600 ppb) under dark and UV illumination. Toluene removal efficiency reached 91% over CSAT-PET, while it was only 62% over pure TiO2 filter. About 40% of toluene removal was achieved by adsorption on CSAT-PET. Furthermore, CSAT-PET showed robust performance for selected face velocity ranging from 0.5 to 1.5 m/s and, the reaction rate followed Langmuir-Hinshelwood model. FTIR study identified benzaldehyde and benzoic acid as adsorbed intermediates. A UV-induced filter regeneration partially released the adsorbed species. CSAT-PET showed consistent toluene removal and intact morphology over five degradation cycles. The Box-Behnken design (BBD) in RSM was applied to optimize the filter preparation method. The optimum values of TiO2, AC and CS loading were 38.3 g/m2, 52.6 g/m2 and 2.06% (w/v), respectively which exhibited highest removal efficiency for toluene (93%). The proposed methodology can be adapted to fabricate low-cost, stable, and reusable photocatalytic filter for air purification applications.
关键词： Volatile organic compounds,Air filter,Photocatalytic oxidation,Titanium dioxide,Activated carbon,Self-assembly
更新于2025-09-19 17:13:59
-
[IEEE 2019 IEEE International Symposium on Olfaction and Electronic Nose (ISOEN) - Fukuoka, Japan (2019.5.26-2019.5.29)] 2019 IEEE International Symposium on Olfaction and Electronic Nose (ISOEN) - Odorant-binding protein-based optoelectronic tongue and nose for sensing volatile organic compounds
摘要： We developed an array of odorant-binding protein mutants with various binding properties. The same design is suitable for the detection and identification of volatile organic compounds (VOCs) both in the liquid phase and in the gas phase by surface plasmon resonance imaging. The obtained optoelectronic tongue is highly selective at low concentrations of VOCs with a low detection limit, but a narrow linear range. In comparison, the optoelectronic nose gives a much higher signal to noise ratio, but the discrimination of VOCs from different chemical classes requires kinetic data to get rid of non-specific signals. This work shows that these optoelectronic tongue and nose are promising for numerous applications, each system having its own advantages.
关键词： electronic tongue,surface plasmon resonance imaging,electronic nose,Odorant-binding proteins,volatile organic compound
更新于2025-09-19 17:13:59
-
Solvent Engineering Using a Volatile Solid for Highly Efficient and Stable Perovskite Solar Cells
摘要： A strategy for efficaciously regulating perovskite crystallinity is proposed by using a volatile solid glycolic acid (HOCH2COOH, GA) in an FA0.85MA0.15PbI3 (FA: HC(NH2)2; MA: CH3NH3) perovskite precursor solution that is different from the common additive approach. Accompanied with the first dimethyl sulfoxide sublimation process, the subsequent sublimation of GA before 150 °C in the FA0.85MA0.15PbI3 perovskite film can artfully regulate the perovskite crystallinity without any residual after annealing. The improved film formation upon GA modification induced by the strong interaction between GA and Pb2+ delivers a champion power conversion efficiency (PCE) as high as 21.32%. In order to investigate the role of volatility in perovskite solar cells (PSCs), nonvolatile thioglycolic acid (HSCH2COOH, TGA) with a similar structure to GA is utilized as an additive reference. Large perovskite grains are obtained by TGA modification but with obvious pinholes, which directly leads to an increased defect density accompanied by a decline in PCE. Encouragingly, the champion PCE achieved for GA-based PSC device (21.32%) is almost 13% or 20% higher than those of the control device or TGA-based device. In addition, GA-modified PSCs exhibit the best stability in light-, thermal-, and humidity-based tests due to the improved film formation.
关键词： pinholes,solvent engineering,volatile,crystal growth,perovskite solar cells
更新于2025-09-19 17:13:59
-
Femtosecond Laser-inscribed Non-volatile Integrated Optical Switch in Fused Silica based on Microfluidics-controlled Total Internal Reflection
摘要： We demonstrate a non-volatile optical power switch, fabricated by femtosecond laser inscription in a fused silica substrate, with switching operation based on microfluidics-controlled total internal reflection. The switch consists of crossed waveguides and a rectangular, high aspect ratio microfluidic channel, located at the waveguide crossing. The switching between total internal reflection and transmission at the channel wall is determined by the refractive index of the medium inside the channel. Femtosecond laser inscription allows for co-integration of low-loss optical waveguides and channels with smooth sidewalls and thus the fabrication of low insertion loss switches that are broadband and show low polarization dependent losses. The measured total internal reflection loss of the fabricated switch is about 1.5 dB at the wavelength 1550 nm. The loss due to transmission through the channel filled with refractive index matching liquid is about 0.5 dB. Detailed finite time domain and beam propagation method difference simulations of the switch’s performance indicate that the losses can be further reduced by optimizing its geometry, together with further adjusting the inscription parameters.
关键词： Fused silica,Non-volatile,Single mode waveguides,Total internal reflection,Microfluidics,Femtosecond laser inscription,integrated optical switch
更新于2025-09-19 17:13:59
-
Monitoring of active constituents of turmeric ( <i>Curcuma longa</i> L.) rhizome stored under supplemented white LED-light with different light intensities
摘要： Previous research showed possible applications of supplemented light to increase active compounds in harvested underground part of medicinal plants. Accordingly, the effect of supplementing white LED (light emitting diode) at different light intensities on the main constituents (curcumin, demethoxycurcumin, bisdemethoxycurcumin) of turmeric (Curcuma longa L.) rhizomes was investigated every week during storage. Rhizomes were stored for six weeks at room temperature of 24.7-34.5°C and 56-76% RH. During storage, rhizomes were illuminated with varied number (0 (control), 1, 2 or 3 tube (s)) of white LEDs at light intensities of 0 μmol m-2 s-1, 14-15 μmol m-2 s-1, 41-42 μmol m-2 s-1 and 61-62 μmol m-2 s-1, respectively. The LEDs were operated for 6 h (3:00 to 6:00 am and 6:00 to 9:00 pm) daily. Concentrations of curcuminoid, crude extracts and volatile oil fluctuated during storage. There was an increase in these attributes during the first week of storage and then a decline thereafter till week 4. The highest increase in all parameters occurred in week 5 and decreased at week 6 where there were significant differences among treatments (p<.05). Under the treatment using 61-62 μmol m-2 s-1 of white light LEDs, curcuminoid content (4.42% w/w) and crude extract (5.72% w/v) were 10.78 and 16.02% greater than the control. There was no significant difference in volatile oil content (1.10-2.10%).
关键词： crude extract,storage,Curcuma longa,curcumin,Zingiberaceae,dormancy,volatile oil
更新于2025-09-16 10:30:52