Sandwich-Structured Silver Nanowire Transparent Conductive Films with 3H Hardness and Robust Flexibility for Potential Applications in Curved Touch Screens

All-Solution-Processed Molybdenum Oxide-Encapsulated Silver Nanowire Flexible Transparent Conductors with Improved Conductivity and Adhesion

A novel transparent conductive conductor composed of a silver nanowire (AgNW) network and MoO_x on a flexible polyethylene terephthalate (PET) substrate, with contemporaneously improved adhesion and reduced resistivity, is prepared using the full-solution process without high-temperature annealing. Under the optimized conditions, a MoO_x/AgNW/MoO_x multilayer is achieved, which shows much superior optoelectronic performance to that obtained from ITO with a high optical transmittance of 89.2% and a low sheet resistance of ∼12.5 Ω/sq. Unlike pure AgNW films, the sheet resistance is little changed after the tape and ultrasonication tests, illustrating a very strong adhesion to the PET substrate after the encapsulation of MoO_x. Moreover, the multilayer film exhibits excellent stability to resist mechanical bending and acid damage. In addition, the successful implementation of the flexible transparent heater demonstrates the practical application value of the electrode.

Enhanced stability of silver nanowire transparent conductive films against ultraviolet light illumination

Silver nanowires are susceptible to degradation under ultraviolet (UV) light illumination. Encapsulating silver nanowire transparent conductive films (AgNW TCFs) with UV shielding materials usually result in the increasing of the sheet resistance or the decrease of the visible light transparency. Herein, we combine a reducing species (FeSO₄) and a thin layer (overcoating) of UV shielding material to solve the stability and the optical performance issues simultaneously. The AgNW TCFs show excellent stability under continuous UV light illumination for 14 h, and their sheet resistance varies only 6%. The dramatic enhancement of the stability against UV light illumination for as-obtained TCFs will make them viable for real-world applications in touch panels and displays.

Ascorbic Acid-Assisted One-Step Chemical Reaction To Design an Ultralong Silver Nanowire Structure for a Highly Transparent Flexible Conducting Film

Increasing the length of silver nanowires (AgNWs) has been demonstrated as an effective measure to enhance their optoelectronic properties by reducing light attenuation. Herein, we report a unique modified polyol synthesis of AgNWs with average length as long as ∼270 μm in a high yield of ∼90%. The synthesis of ultralong AgNWs involves the employment of ascorbic acid in the polyol approach. The strong reducing action of ascorbic acid allows the reduction of silver precursors to occur at a relatively low temperature, wherein the lateral growth of AgNWs is restrained because of efficient surface passivation via the dual function of poly-vinylpyrrolidone and ascorbic acid. The photoelectric properties of the as-synthesized ∼270 μm AgNW film show a noteworthy transmittance of 92.61% with a low haze of 1.35% at a sheet resistance of ∼322 Ω sq^-1. In addition, the AgNW film shows distinguished mechanical property and relatively high electrical stability. The breakthrough in the length confinement of AgNWs is a highly expected step to prepare AgNW films with excellent performance.

Preparation of Nano Silver Paste and Applications in Transparent Electrodes via Electric-Field Driven Micro-Scale 3D Printing

Nano-silver paste, as an important basic material for manufacturing thick film components, ultra-fine circuits, and transparent conductive films, has been widely used in various fields of electronics. Here, aiming at the shortcomings of the existing nano-silver paste in printing technology and the problem that the existing printing technology cannot achieve the printing of high viscosity, high solid content nano-silver paste, a nano-silver paste suitable for electric-field-driven (EFD) micro-scale 3D printing is developed. The result shows that there is no oxidation and settlement agglomeration of nano-silver paste with a storage time of over six months, which indicates that it has good dispersibility. We focus on the printing process parameters, sintering process, and electrical conductivity of nano-silver paste. The properties of the nano-silver paste were analyzed and the feasibility and practicability of the prepared nano-silver paste in EFD micro-scale 3D printing technology were verified. The experiment results indicate that the printed silver mesh which can act as transparent electrodes shows high conductivity (1.48 Ω/sq) and excellent transmittance (82.88%). The practical viability of the prepared nano-silver paste is successfully demonstrated with a deicing test. Additionally, the experimental results show that the prepared silver mesh has excellent heating properties, which can be used as transparent heaters.

Highly accurate particulate matter detection assisted by an air heater based on a silver nanowire film

Recently, many studies have been carried out to solve the particulate matter pollution problem. However, the detection accuracy for particulate matter in the atmosphere remains unsatisfactory due to the influence of the air relative humidity. Herein, we report a Ag nanowire film air heater to enhance the detection accuracy through internal heating. From air temperature and air relative humidity relationship analysis, it has been found that the Ag nanowire film air heater can form the most suitable air relative humidity in the detection system, thereby enhancing the detection accuracy. Consequently, the Ag nanowire film air heater-assisted light scattering particulate matter detector has achieved tremendous enhancement in its detection accuracy, which is comparable with the data obtained by the beta gauge method. Film resistance plays a key role in internal air temperature distribution and the resultant air relative humidity at given voltages. To achieve the most suitable air relative humidity for continuous online monitoring, response time and power consumption should be balanced. Therefore, guidance for designing Ag nanowire films with proper resistance used in an optional-sized detector has been given for quick response, high accuracy and low power consumption. This work is of significance for providing insight for future studies in particulate matter detection and pollution remediation.