Solvent exchange synthesis of C-doped ZnO bunches and their enhanced ethanol sensing properties

In this study, zinc complex bunches have been synthesized by a simple solvent exchange approach without any surfactant at room temperature. The zinc complex can be converted to C-doped ZnO bunches by a subsequent annealed process at 500∘C for 2[Formula: see text]h. The morphology and structure results show that the rectangle-shaped ZnO bunches are assembled by ZnO disks. The as-prepared C-doped ZnO bunches exhibit the highest sensitivity to 100[Formula: see text]ppm ethanol vapor at 240∘C. In addition the C-doped ZnO bunches also show excellent response-recover properties and stability, and good linearity in the range of 5–400[Formula: see text]ppm for potential applications.

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Preparation of Ethanol-Sensing Gas Sensor Based on PECH/Multi-Wall Carbon Nanotubes Sensitive Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.936.419 ◽

2014 ◽

Vol 936 ◽

pp. 419-423

Author(s):

Wei Yao ◽

Guang Zhong Xie ◽

Hui Ling Tai ◽

Ya Dong Jiang ◽

Yong Zhou

Keyword(s):

Carbon Nanotubes ◽

Composite Film ◽

Gas Sensor ◽

Room Temperature ◽

Composite Films ◽

Ethanol Vapor ◽

Interdigitated Electrodes ◽

Multi Wall Carbon Nanotubes ◽

Ethanol Sensing ◽

Better Than

Abstract: In this paper, Polyepichlorohyron(PECH)/multi-wall carbon nanotubes(MWCNTs) composite films and PECH/multi-wall carbon nanotubes twolayer film were deposited on interdigitated electrodes by airbrush technology to detect ethanol vapor of various concentrations at room temperature. Thickness and structure of the film were taken into account, so films of different thicknesses and with different structures were prepared respectively. The responses of the sensors to ethanol showed that composite film had a higher response thantwolayer film, and the thick composite film performed better than its counterpart when they were exposed to ethanol vapor.

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DNA Inspirited Rational Construction of Nonconventional Luminophores with Efficient and Color-Tunable Afterglow

10.26434/chemrxiv.11786448 ◽

2020 ◽

Author(s):

Yunzhong Wang ◽

Saixing Tang ◽

Yating Wen ◽

Shuyuan Zheng ◽

Bing Yang ◽

...

Keyword(s):

Rational Design ◽

Room Temperature ◽

Double Helix ◽

Mechanical Grinding ◽

Room Temperature Phosphorescence ◽

Color Tunable ◽

Potential Applications ◽

Rational Construction ◽

Double Helix Structure ◽

Made In

<div>Persistent room-temperature phosphorescence (p-RTP) from pure organics is attractive </div><div>due to its fundamental importance and potential applications in molecular imaging, </div><div>sensing, encryption, anticounterfeiting, etc.1-4 Recently, efforts have been also made in </div><div>obtaining color-tunable p-RTP in aromatic phosphors5 and nonconjugated polymers6,7. </div><div>The origin of color-tunable p-RTP and the rational design of such luminogens, </div><div>particularly those with explicit structure and molecular packing, remain challenging. </div><div>Noteworthily, nonconventional luminophores without significant conjugations generally </div><div>possess excitation-dependent photoluminescence (PL) because of the coexistence of </div><div>diverse clustered chromophores6,8, which strongly implicates the possibility to achieve </div><div>color-tunable p-RTP from their molecular crystals assisted by effective intermolecular </div><div>interactions. Here, inspirited by the highly stable double-helix structure and multiple </div><div>hydrogen bonds in DNA, we reported a series of nonconventional luminophores based on </div><div>hydantoin (HA), which demonstrate excitation-dependent PL and color-tunable p-RTP </div><div>from sky-blue to yellowish-green, accompanying unprecedentedly high PL and p-RTP </div><div>efficiencies of up to 87.5% and 21.8%, respectively. Meanwhile, the p-RTP emissions are </div><div>resistant to vigorous mechanical grinding, with lifetimes of up to 1.74 s. Such robust, </div><div>color-tunable and highly efficient p-RTP render the luminophores promising for varying </div><div>applications. These findings provide mechanism insights into the origin of color-tunable </div><div>p-RTP, and surely advance the exploitation of efficient nonconventional luminophores.</div>

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Controlled Growth and Characterization Ag/ZnO Nanotetrapods for Humidity Sensing

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207321666180717120417 ◽

2018 ◽

Vol 21 (7) ◽

pp. 462-467

Author(s):

Babak Sadeghi

Keyword(s):

Room Temperature ◽

Zinc Complex ◽

Water Solution ◽

Particle Morphology ◽

Quick Response ◽

Separation System ◽

Humidity Sensing ◽

Sensor Material ◽

Highly Sensitive

Aim and Objective: Ultrafine Ag/ZnO nanotetrapods (AZNTP) have been prepared successfully using silver (I)–bis (oxalato) zinc complex and 1, 3-diaminopropane (DAP) with a phase separation system, and have been injected into a diethyl/water solution. Materials and Methods: This crystal structure and lattice constant of the AZNTP obtained were investigated by means of a SEM, XRD, TEM and UV-vis spectrum. Results: The results of the present study demonstrated the growth and characterization AZNTP for humidity sensing and DAP plays a key role in the determination of particle morphology. AZNTP films with 23 nm in arm diameter have shown highly sensitive, quick response sensor material that works at room temperature.

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Photoluminescence and Magnetic Properties of Undoped and (Mn, Co) co-doped ZnO Nanoparticles

Current Nanoscience ◽

10.2174/1573413715666191010162626 ◽

2020 ◽

Vol 16 (4) ◽

pp. 655-666

Author(s):

Mona Rekaby

Keyword(s):

Magnetic Properties ◽

Zno Nanoparticles ◽

Room Temperature ◽

Magnetic Measurements ◽

Structural Defects ◽

Ferromagnetic Behavior ◽

Secondary Phases ◽

Antiferromagnetic Ordering ◽

Doped Zno ◽

Co Doped

Objective: The influence of Manganese (Mn2+) and Cobalt (Co2+) ions doping on the optical and magnetic properties of ZnO nanoparticles was studied. Methods: Nanoparticle samples of type ZnO, Zn0.97Mn0.03O, Zn0.96Mn0.03Co0.01O, Zn0.95Mn0.03 Co0.02O, Zn0.93Mn0.03Co0.04O, and Zn0.91Mn0.03Co0.06O were synthesized using the wet chemical coprecipitation method. Results: X-ray powder diffraction (XRD) patterns revealed that the prepared samples exhibited a single phase of hexagonal wurtzite structure without any existence of secondary phases. Transmission electron microscope (TEM) images clarified that Co doping at high concentrations has the ability to alter the morphologies of the samples from spherical shaped nanoparticles (NPS) to nanorods (NRs) shaped particles. The different vibrational modes of the prepared samples were analyzed through Fourier transform infrared (FTIR) measurements. The optical characteristics and structural defects of the samples were studied through Photoluminescence (PL) spectroscopy. PL results clarified that Mn2+ and Co2+ doping quenched the recombination of electron-hole pairs and enhanced the number of point defects relative to the undoped ZnO sample. Magnetic measurements were carried out at room temperature using a vibrating sample magnetometer (VSM). (Mn, Co) co-doped ZnO samples exhibited a ferromagnetic behavior coupled with paramagnetic and weak diamagnetic contributions. Conclusion: Mn2+ and Co2+ doping enhanced the room temperature Ferromagnetic (RTFM) behavior of ZnO. In addition, the signature for antiferromagnetic ordering between the Co ions was revealed. Moreover, a strong correlation between the magnetic and optical behavior of the (Mn, Co) co-doped ZnO was analyzed.

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Green Solvents as an Alternative to DMF in ZIF-90 Synthesis

Molecules ◽

10.3390/molecules26061573 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1573

Author(s):

Aljaž Škrjanc ◽

Ciara Byrne ◽

Nataša Zabukovec Logar

Keyword(s):

Room Temperature ◽

Product Yield ◽

Solvent Exchange ◽

Green Solvents ◽

Zeolitic Imidazolate Framework ◽

Short Treatment ◽

Molar Ratios ◽

Primary Particles ◽

High Product Yield

The use of green solvents as an alternative to dimethylformamide (DMF) in the synthesis of zeolitic imidazolate framework-90 (ZIF-90) was investigated. Two biobased aprotic dipolar solvents CyreneTM and γ-valerolactone (GVL) proved to successfully replace DMF in the synthesis at room temperature with a high product yield. While the CyreneTM—based product shows reduced porosity after activation, the use of GVL resulted in materials with preserved crystallinity and porosity after activation, without prior solvent exchange and a short treatment at 200 °C. The primary particles of 30 nm to 60 nm in all products further form agglomerates of different size and interparticle mesoporosity, depending on the type and molar ratios of solvents used.

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Room-Temperature Benzene Sensing with Au-Doped ZnO Nanorods/Exfoliated WSe2 Nanosheets and Density Functional Theory Simulations

ACS Applied Materials & Interfaces ◽

10.1021/acsami.1c03884 ◽

2021 ◽

Author(s):

Dongzhi Zhang ◽

Wenjing Pan ◽

Lanjuan Zhou ◽

Sujing Yu

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Room Temperature ◽

Zno Nanorods ◽

Functional Theory ◽

Doped Zno

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Foldable and washable textile-based OLEDs with a multi-functional near-room-temperature encapsulation layer for smart e-textiles

npj Flexible Electronics ◽

10.1038/s41528-021-00112-0 ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

So Yeong Jeong ◽

Hye Rin Shim ◽

Yunha Na ◽

Ki Suk Kang ◽

Yongmin Jeon ◽

...

Keyword(s):

Room Temperature ◽

Wearable Electronics ◽

Ambient Conditions ◽

Light Emitting ◽

Stable Operating ◽

Mechanical Durability ◽

Potential Applications ◽

Wearable Electronic ◽

Data Signal ◽

Wearable Electronic Devices

AbstractWearable electronic devices are being developed because of their wide potential applications and user convenience. Among them, wearable organic light emitting diodes (OLEDs) play an important role in visualizing the data signal processed in wearable electronics to humans. In this study, textile-based OLEDs were fabricated and their practical utility was demonstrated. The textile-based OLEDs exhibited a stable operating lifetime under ambient conditions, enough mechanical durability to endure the deformation by the movement of humans, and washability for maintaining its optoelectronic properties even in water condition such as rain, sweat, or washing. In this study, the main technology used to realize this textile-based OLED was multi-functional near-room-temperature encapsulation. The outstanding impermeability of TiO2 film deposited at near-room-temperature was demonstrated. The internal residual stress in the encapsulation layer was controlled, and the device was capped by highly cross-linked hydrophobic polymer film, providing a highly impermeable, mechanically flexible, and waterproof encapsulation.

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Enhanced room-temperature ethanol sensing performance of porous MoO3/V0.13Mo0.87O2.935 heterostructures self-assembled with 2D nanosheets

CrystEngComm ◽

10.1039/d1ce00311a ◽

2021 ◽

Author(s):

Jia Guo ◽

Hang Li ◽

Shushu Chu ◽

Qi Zhang ◽

Ziqiong Lin ◽

...

Keyword(s):

Room Temperature ◽

Self Assembled ◽

Ethanol Sensing ◽

2D Nanosheets ◽

Sensing Performance

Porous MoO3/V0.13Mo0.87O2.935 heterostructures self-assembled with 2D nanosheets have been primarily prepared by a facile method for effectively detecting ethanol at room temperature. V0.13Mo0.87O2.935 phase contributes to the modified microspheres and...

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Giant room temperature elastocaloric effect in metal-free thin-film perovskites

npj Computational Materials ◽

10.1038/s41524-021-00599-1 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Cheng Li ◽

Yu Hui Huang ◽

Jian-Jun Wang ◽

Bo Wang ◽

Yong Jun Wu ◽

...

Keyword(s):

Thin Films ◽

Solid State ◽

Room Temperature ◽

Entropy Change ◽

Stress Change ◽

Chemical Doping ◽

Metal Free ◽

Organic Ferroelectrics ◽

Potential Applications ◽

Unit Stress

AbstractSolid-state refrigeration which is environmentally benign has attracted considerable attention. Mechanocaloric (mC) materials, in which the phase transitions can be induced by mechanical stresses, represent one of the most promising types of solid-state caloric materials. Herein, we have developed a thermodynamic phenomenological model and predicted extraordinarily large elastocaloric (eC) strengths for the (111)-oriented metal-free perovskite ferroelectric [MDABCO](NH4)I3 thin-films. The predicted room temperature isothermal eC ΔSeC/Δσ (eC entropy change under unit stress change) and adiabatic eC ΔTeC/Δσ (eC temperature change under unit stress change) for [MDABCO](NH4)I3 are −60.0 J K−1 kg−1 GPa−1 and 17.9 K GPa−1, respectively, which are 20 times higher than the traditional ferroelectric oxides such as BaTiO3 thin films. We have also demonstrated that the eC performance can be improved by reducing the Young’s modulus or enhancing the thermal expansion coefficient (which could be realized through chemical doping, etc.). We expect these discoveries to spur further interest in the potential applications of metal-free organic ferroelectrics materials towards next-generation eC refrigeration devices.

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