An Optically Flat Conductive Outcoupler Using Core/Shell Ag/ZnO Nanochurros

Increasing Silver Nanowire Network Stability through Small Molecule Passivation

Silver nanowire (AgNW) transparent electrodes show promise as an alternative to indium tin oxide (ITO). However, these nanowire electrodes degrade in air, leading to significant resistance increases. We show that passivating the nanowire surfaces with small organic molecules of 11-mercaptoundecanoic acid (MUA) does not affect electrode transparency contrary to typical passivation films, and is inexpensive and simple to deposit. The sheet resistance of a 32 nm diameter silver nanowire network coated with MUA increases by only 12% over 120 days when exposed to atmospheric conditions but kept in the dark. The increase is larger when exposed to daylight (588%), but is still nearly two orders of magnitude lower than the resistance increase of unpassivated networks. The difference between the experiments performed under daylight versus the dark exemplifies the importance of testing passivation materials under light exposure.

Effect of silane functionalized graphene prepared by a supercritical carbon dioxide process on the barrier properties of polyethylene terephthalate composite films

In this work, a simple and eco-friendly strategy to modify graphene nanoplatelets (GNs) with different silane coupling agents using a supercritical carbon dioxide (Sc-CO₂) process has been presented, and effect of the modified GNs on the oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) of GN/PET composite films was studied. FT-IR, SEM, EDX and TG results indicated that Sc-CO₂ process was an effective strategy to modify GNs with silane coupling agents. Addition of the modified GNs into PET matrix could greatly decrease the OTR and WVTR values of the GNs/PET composite films, and the WVTR of GNs560/PET composite film and OTR of GNs550/PET composite film were respectively decreased about 90.08% and 58.04%, as compared to those of GNs/PET composite film. It is found that the gas barrier property of GN/PET composites was attributed to not only the tortuous path effect caused by GNs themselves and the interfacial interaction, but also the affinity of binding bonds between GNs and the polymer to the gas molecules. It is believed that this work provided a strategy to design and prepare CN/polymer composites with high barrier properties.

Adding silane modified GNs prepared by a Sc-CO₂ process into a PET matrix could greatly enhance the barrier properties of the GNs/PET composites.The barrier performance of GNs/PET composites was greatly enhanced by modifying GNs with silane coupling agents via Sc-CO₂ process.

Comprehensive Stability Improvement of Silver Nanowire Networks via Self-Assembled Mercapto Inhibitors

Instability of silver nanowire (AgNW) has been regarded as a major obstacle to its practical applications in optoelectrical devices as transparent electrodes. Physical barrier layers such as polymer, metal, and graphene have been generally employed to improve the stability of AgNW in previous study. Herein, we first report self-assembled organothiols as an inhibitor for AgNW to achieve an overall enhancement in antioxidation, antisulfidation, thermal stability, and anti-electromigration. The self-assembled monolayers (SAMs) of phenyl azoles, methoxy silane, and methyl alkane were formed on the surface of AgNW via Ag-S covalent bond as barrier layers which provided protective effects against corrosives (e.g., O₂, H₂S). In particular, the decoration of 2-mercaptobenzimidazole (MBI) offered the best resistance to H₂S and excellent stability under a high-temperature and high-humidity environment (85 °C and 85 RH %) for 4 months. Moreover, different SAMs exhibited a stabilizing or destabilizing effect on Plateau-Rayleigh instability of AgNW, which realized the tunability of degradation temperature of AgNWs, for example, increasing by ≥100 °C with MBI SAM or decreasing by ∼50 °C with octadecanethiol SAM compared with pristine AgNWs. Notably, the MBI-decorated AgNWs could survive at 400 °C which is by far the highest bearing temperature for solution-processed AgNW film. As a result, a transparent heater made of the MBI-AgNWs exhibited superior heating characteristics (higher working temperature and durability), as compared with the pristine AgNW-based heater. Our findings on the organothiols decoration not only provide a new paradigm in overall stability improvement of NW of noble metals but also show the potential in morphology controllability of metal NW.