Modeling and Analysis of D–shaped Plasmonic Refractive Index and Temperature Sensor Using Photonic Crystal Fiber

A plasmonic D–shaped photonic crystal fiber (PCF) sensor for refractive index (RI) and temperature is designed and studied in this paper. The RI channel is made up of a silver thin layer deposited on the plane of the D–type structure, and the temperature sensing channel is formed by a silver nanowire and benzene filled in an elliptical hole in the PCF. The designed structure can be used for temperature and RI sensing via coupling between the core–guided modes and the surface plasmon modes around Ag nanowire and Ag thin layer. The coupling characteristic and sensing performance of the proposed dual–functional sensor is studied in the present work. Results show that the maximum sensitivity in terms of RI units (RIU) is 6.9 µm/RIU in the range of 1.33–1.38, and the maximum temperature sensitivity is 3 µm /°C in the range of 27°C–67°C.

Negative Effects of Annealed Seed Layer on the Performance of ZnO-Nanorods Based Nitric Oxide Gas Sensor

Nitric oxide (NO) is a toxic gas, which is dangerous for human health and causes many respiratory infections, poisoning, and lung damage. In this work, we have successfully grown ZnO nanorod film on annealed ZnO seed layer in different ambient temperatures, and the morphology of the nanorods sensing layer that affects the gas sensing response to nitric oxide (NO) gas were investigated. To acknowledge the effect of annealing treatment, the devices were fabricated with annealed seed layers in air and argon ambient at 300 °C and 500 °C for 1 h. To simulate a vertical device structure, a silver nanowire electrode covered in ZnO nanorod film was placed onto the hydrothermal grown ZnO nanorod film. We found that annealing treatment changes the seed layer’s grain size and defect concentration and is responsible for this phenomenon. The I–V and gas sensing characteristics were dependent on the oxygen defects concentration and porosity of nanorods to react with the target gas. The resulting as-deposited ZnO seed layer shows better sensing response than that annealed in an air and argon environment due to the nanorod morphology and variation in oxygen defect concentration. At room temperature, the devices show good sensing response to NO concentration of 10 ppb and up to 100 ppb. Shortly, these results can be beneficial in the NO breath detection for patients with chronic inflammatory airway disease, such as asthma.

The phonon scattering mechanism and its effect on temperature dependent thermal and thermoelectric properties of the silver nanowire

In this work, the electron-phonon, the phonon-phonon, and phonon structure scattering mechanisms and the effect on the thermal and thermoelectric properties of the silver nanowire (AgNW) are investigated in temperature...

Accelerated and Outdoor Weathering of Silver Nanowire Transparent Conductors under Electrical Stress in Pseudo-modules

In realistic applications, silver nanowires (AgNWs) are encapsulated in optoelectrical devices to function as transparent conductors and electrodes. Environmental stressors along with the essential electrical stress are inevitably harmful to the AgNWs inside the devices. Herein, to investigate the degradation behavior discrepancy between materials-level and device-level tests, we adopted pseudo-module to mimic the encapsulation. The pseudo-module allows the application of electrical stress and facilitates the interim specimen access for materials characterization through assembly-disassembly. Indoor accelerated and outdoor weathering tests with applied electrical stress to the pseudo-module encapsulated AgNW networks were performed. The impaired optoelectrical properties and morphological changes of AgNWs due to multiple or individual stressor(s) are investigated. Results indicate UVA exposure at elevated temperature coupled with electrical stress is responsible for the electrical failure of AgNW networks. Sulfidation that depresses optical transparency of AgNW networks is prone to occur at lower temperature. This work provides unambiguous degradation behaviors of AgNWs inside encapsulants, helping to improve the design of AgNWs related optoelectrical devices in the applications of solar irradiation environments.

Preparation of Double-Layer Crossed Silver Nanowire Film and Its Application to OLED

Ordered silver nanowire (AgNW) film can effectively reduce the density of nodes, reduce the roughness of the film, and increase its conductivity and transmittance. In this paper, a double-layer crossed AgNW grid film was prepared by the auxiliary stirring method. The average transmittance of the double-layer crossed AgNW grid film was found to be 80% in the 400–1000 nm band, with a square resistance of 35 Ω/sq. As a transparent conductive anode material, the ordered AgNW film was applied to fabricate a flexible green organic light-emitting diode (OLED). The experimental results showed that the threshold voltage of the OLED was only 5 V and the maximum luminance was 1500 cd/m2.