Ag nanowire (NW) films obtained by the spraying the Ag NWs on the substrates were nano-welded by rapid thermal annealing (RTA) process and the effect of RTA process on the change of sheet resistance and optical transmittance of the Ag NW films was investigated. The increased number of Ag NW sprays on the substrate decreased the sheet resistance but also decreased the optical transmittance. By the annealing for 60 sec in a nitrogen environment to 225-250 degrees C, the sheet resistance of Ag NW film could be decreased to about 50%, even though it was accompanied by the slight decrease of optical transmittance less than 5%. The decrease of sheet resistance was related to the nano-welding of the Ag NW junctions and the slight decrease of optical transmittance was related local melting of the Ag NWs and spreading on the substrate surface. Through the nano-welding by RTA process, the Ag NW film with the sheet resistance of -20 Ω/sq. and the optical transmittance of 93% could be obtained.

Silver nanowire (AgNW) has been studied as an important material for next-generation wearable devices due to its high flexibility, high electrical conductivity and high optical transmittance. However, the inherently high surface roughness of AgNWs and low adhesion to the substrate still need to be resolved for various device applications. In this study, an embedded two-dimensional (2D) Ag nanomesh was fabricated by mechanical press welding of AgNW networks with a three-dimensional (3D) fabric shape into a nanomesh shape, and by embedding the Ag nanomesh in a flexible substrate. The effect of the embedded AgNWs on the physical and electrical properties of a flexible transparent electrode was investigated. By forming embedded nanomesh-type AgNWs from AgNW networks, improvements in physical and electrical properties, such as a 43% decrease in haziness, 63% decrease in sheet resistance, and 26% increase in flexibility, as well as improved adhesion to the substrate and low surface roughness, were observed.

In this study, metallic nanowires (M-NWs) such as silver nanowires (AgNWs) and copper nanowires (CuNWs) were welded only at junctions resistively by a novel method using an indirect Eddy current through an inductive power transfer. By applying an inductive power of 45 kHz alternating current power indirectly for 6 s to the M-NW network deposited on polymer substrates, a decrease of sheet resistance up to ∼67.9% for AgNWs and ∼49.9% for CuNWs could be obtained without changing the optical transmittance. For AgNWs, after the welding a decrease of surface roughness could also be observed from 44.5 nm to 26.3 nm, which is similar to the height of a single layer AgNW (22.2 nm) for a bilayer junction. For AgNWs coated on a transparent flexible substrate, after the cyclic bending of 10 000 times, no change of resistance (ΔR/R0) of the AgNWs after the welding was observed and the welded AgNWs were not easily peeled off from the substrate. It is believed that this novel welding method can be applied not only to all kinds of M-NWs on various flexible low-temperature polymer substrates, but also to large areas at a short time and at low cost.

Graphene nanoplatelets (GNP) have attracted considerable attention due to their high yield and fabrication route that is scalable to enable graphene production. However, the absence of a means of fabricating a transparent and conductive GNP film has been the biggest obstacle to the replacement of pristine graphene. Here, we report on a novel means of fabricating uniform and thin GNP-based high-performance transparent electrodes for flexible and stretchable optoelectronic devices involving the use of an adhesive polymer layer (PMMA) as a GNP layer controller and by forming a hybrid GNP/AgNW electrode embedded on PET or PDMS. Relative to the commercially available indium tin oxide (ITO) film on a PET substrate, a GNP-based electrode composed of hybrid GNP/AgNW on PET exhibits superb optical, physical, and electrical properties: a sheet resistance of 12 Ω sq with 87.4% transmittance, a variable work function from 4.16 to 5.26 eV, an ultra-smooth surface, a rate of resistance increase of only 4.0% after 100 000 bending cycles, stretchability to 50% of tensile strain, and robust stability against oxidation. Moreover, the GNP-based electrode composed of hybrid Cl-doped GNP/AgNW shows outstanding performance in actual organic light-emitting diodes (OLEDs) by exhibiting an increased current efficiency of 29.5% and an increased luminous efficiency of 36.2%, relative to the commercial ITO electrode on PET.

Keratinocyte Tight Junctions (TJs) in the epidermal layer play a crucial role in skin barrier function. An effective immune response in skin is usually initiated by dendritic Antigen Presenting Cells (APCs) in the epidermis and dermis and is finally executed by T lymphocytes. The aim of this study was to investigate whether increased keratinocyte TJ proteins affect immune responses mediated by Immature Dendritic Cells (imDCs). Keratinocytes were treated with the peptide AdhPep-10-2 (10 nM) and then cocultured with DCs for 24 h. Cytokine production was measured by ELISA and a Luminex Multiplexing System. DCs and T cell subsets were analyzed by flow cytometry. Expression of TJ proteins by keratinocytes treated with AdhPep-10-2 increased markedly, whereas CXCL1 chemokine secretion decreased. Coculture of imDCs with AdhPep-10-2-treated keratinocytes inhibited maturation of DCs, reduced production of pro-inflammatory cytokines, and increased the regulatory T (Treg) cell population in the presence of LPS. These results suggest that AdhPep-10-2 peptide increases keratinocyte TJ proteins, thereby inducing anti-inflammatory responses by imDCs under inflammatory conditions. Taken together, these studies show strong possibility that increased keratinocyte TJ proteins play a key role in DC-mediated immunity.