With a series of widespread applications, resistive gas sensors are considered to be promising candidates for gas detection, benefiting from their small size, ease-of-fabrication, low power consumption and outstanding maintenance properties. One-dimensional (1-D) nanomaterials, which have large specific surface areas, abundant exposed active sites and high length-to-diameter ratios, enable fast charge transfers and gas-sensitive reactions. They can also significantly enhance the sensitivity and response speed of resistive gas sensors. The features and sensing mechanism of current resistive gas sensors and the potential advantages of 1-D nanomaterials in resistive gas sensors are firstly reviewed. This review systematically summarizes the design and optimization strategies of 1-D nanomaterials for high-performance resistive gas sensors, including doping, heterostructures and composites. Based on the monitoring requirements of various characteristic gases, the available applications of this type of gas sensors are also classified and reviewed in the three categories of environment, safety and health. The direction and priorities for the future development of resistive gas sensors are laid out.

One-Dimensional Nanomaterials in Resistive Gas Sensor: From Material Design to Application

Organic/inorganic hybrid nanostructures-based dual light-detecting/gas-sensing devices were fabricated. In this research, polycrystalline perylene diimide (PDI) membrane was coated on ZnO nanorods (NRs), functioning as sensing nanocomposites. Multiple material analyses including scanning electron microscope (SEM), energy dispersive spectrometer (EDS), high resolution transmission electron microscopy (HR-TEM), X-ray diffractometer (XRD), Raman spectroscopy, and confocal laser scanning microscopy (CLSM) indicate that organic perylene diimide was successfully deposited on ZnO NRs, forming organic/inorganic membrane on the sensing device. To examine the influence of organic/inorganic hybrid nanostructure on photo-sensing and gas-sensing behaviors, UV light detection and CO gas sensing impulse response were measured. Results reveal that organic/inorganic hybrid nanostructure can effectively enhance UV light and CO gas dual-sensing properties with addition of PDI. The coating of organic PDI on the ZnO NRs not only improves the gas interaction capability and gas-sensing stability but also enhances the UV absorption efficiency. Owing to advantages of low cost, simple fabrication, compact size, and device stability, hybrid PDI/ZnO organic/inorganic light/gas dual-sensing devices are promising for future portable hazardous light and gas sensing applications.

Organic/inorganic hybrid nanostructures of polycrystalline perylene diimide decorated ZnO nanorods highly enhanced dual sensing performance of UV light/CO gas sensors

Zinc oxide (ZnO) nanomaterials are used in various health-related applications, from antimicrobial textiles to wound dressing composites and from sunscreens to antimicrobial packaging. Purity, surface defects, size, and morphology of the nanoparticles are the main factors that influence the antimicrobial properties. In this study, we are comparing the properties of the ZnO nanoparticles obtained by solvolysis using a series of alcohols: primary from methanol to 1-hexanol, secondary (2-propanol and 2-butanol), and tertiary (tert-butanol). While the synthesis of ZnO nanoparticles is successfully accomplished in all primary alcohols, the use of secondary or tertiary alcohols does not lead to ZnO as final product, underlining the importance of the used solvent. The shape of the obtained nanoparticles depends on the alcohol used, from quasi-spherical to rods, and consequently, different properties are reported, including photocatalytic and antimicrobial activities. In the photocatalytic study, the ZnO obtained in 1-butanol exhibited the best performance against methylene blue (MB) dye solution, attaining a degradation efficiency of 98.24%. The comparative study among a series of usual model dyes revealed that triarylmethane dyes are less susceptible to photo-degradation. The obtained ZnO nanoparticles present a strong antimicrobial activity on a broad range of microorganisms (bacterial and fungal strains), the size and shape being the important factors. This permits further tailoring for use in medical applications.

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Influence of the Alcohols on the ZnO Synthesis and Its Properties: The Photocatalytic and Antimicrobial Activities

In the paper the biopolymer substrates were made from nanocellulose (NC), which is extracted from organosolvent reed cellulose using 2,2,6,6-tetramethylpiperidin-1-oxyl reagent (TEMPO). Nickel-based thin films were deposited on the surface of nanocellulose by RF magnetron sputtering. The peculiarities of surface morphology and chemical composition of inorganic material on the surface of biopolymer substrate were studied. Flexible strain sensors were obtained from nickel busbars on the surface of nanocellulose. The influence of overall sizes of nickel busbars on piezoresistive parameters of flexible sensors was established. It was determined that the maximum strain sensitivity is observed for a nickel busbar with a width of 1 mm, a thickness of 250 nm, a length of 15 mm and was 195,8⋆ 10-3 %. The magnitude of drift in time was 0,17 %/min. Obtained strain sensors were tested on mechanical strength depending on nickel busbar sizes. It was shown that the presence of nickel thin film increases the strength of strain sensors by 40%: from 13.8 MPa for pure nanocellulose to 19.5-19.6 MPa for nanocellulose with nickel thin films.

Nickel-based Piezoresistive Sensors Obtained on Flexible Nanocellulose Substrate

Incorporation of hydrophobic-like bisindolo quinoxaline-tips (BIQ-TIPs) aggregation on ZnO nanorods for spectral broadening photodetection

Ultraviolet A light (UV-A, 320-400 nm), which is unblockable by sunscreen, requires careful detection for disease avoidance. In this study, we propose a novel photosensing device capable of detecting UV-A. Cancer-causing UV light can be simultaneously monitored with tiny rapid response sensors for a high carrier transition speed. In our research, a multifunctional ZnO/ZnS nanomaterial hybrid-sprinkled carbon nanotube (CNT) was created for the purpose of fabricating a multipurpose, semiconductorbased application. For our research, ZnO nanorods (NRs) were grown by using a facile hydrothermal method on SiO2 substrate, then vulcanized to form ZnO/ZnS coreshell nanorods, which were sprinkled with carbon nanotubes (CNTs). Results indicate that SiO2/ZnO/ZnS/CNT structures exhibited a stronger conducting current with and without light than those samples without CNTs. Multiple material characterizations of the nanostructures, including of atomic force microscopy (AFM) surface morphology evaluation, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) indicate that CNTs could be successfully spread on top of the ZnO/ZnS coreshell structures. Furthermore, chemical binding properties, material crystallinity, and optical properties were examined by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), and photoluminescence (PL). Owing to their compact size, simple fabrication, and low cost, ZnO/ZnS coreshell NRs/CNT/SiO2-based nanocomposites are promising for future industrial optoelectronic applications.

https://www.mdpi.com/2079-4991/10/8/1521/pdf

Morphological, Material, and Optical Properties of ZnO/ZnS/CNTs Nanocomposites on SiO2 Substrate.

Deposition of high-quality Ge film on Si by PECVD using GeCl4/H2 for fabricating near-infrared photodiodes

Mg-doped InGaZnO (IGZO) electrolyte-insulator-semiconductor (EIS) biosensors were fabricated with multianalyte sensing capability. H+, Na+, and K+ ion sensing behaviors were examined and urea, glucose, and creatine detection through enzymatic reaction was performed. Results indicate that Mg doping IGZO membranes with appropriate annealing had better multi-sensing performance than that of regular membranes. Moreover, multiple material characterizations of membrane nanostructures, including of atomic force microscopy (AFM) surface morphology evaluation, scanning electron microscopy (SEM), and transmission electron microscopy (TEM), and selected area electron diffraction (SAED) were conducted. Material crystalline and chemical binding properties were also performed, including energy dispersive X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDX), and photoluminescence (PL). These detailed studies indicate that the incorporation of Mg in the membrane can form MgO crystals to enhance compactness, crystallization and grainization, which can reinforce the surface sites on the membrane. Mg-doped IGZO EIS multianalyte biosensors show promise for future portable and wearable biosensing applications.

Multianalyte Mg-Doped InGaZnO Electrolyte-Insulator-Semiconductor Biosensors and Multiple Material Characterizations of Membrane Nanostructures

Deposition of GeSn film on Si substrate by plasma-enhanced chemical vapor deposition using GeCl4 and SnCl4 in H2 for developing short-wave infrared Si photonics

Shang Che Tsai

Papers

Organic/inorganic hybrid nanostructures of polycrystalline perylene diimide decorated ZnO nanorods highly enhanced dual sensing performance of UV light/CO gas sensors

Morphological, Material, and Optical Properties of ZnO/ZnS/CNTs Nanocomposites on SiO2 Substrate.

Deposition of high-quality Ge film on Si by PECVD using GeCl4/H2 for fabricating near-infrared photodiodes

Multianalyte Mg-Doped InGaZnO Electrolyte-Insulator-Semiconductor Biosensors and Multiple Material Characterizations of Membrane Nanostructures

Deposition of GeSn film on Si substrate by plasma-enhanced chemical vapor deposition using GeCl4 and SnCl4 in H2 for developing short-wave infrared Si photonics