Large scale silver nanowires network fabricated by MeV hydrogen (H⁺) ion beam irradiation

A random two-dimensional large scale nano-network of silver nanowires (Ag-NWs) is fabricated by MeV hydrogen (H⁺) ion beam irradiation. Ag-NWs are irradiated under H⁺ ion beam at different ion fluences at room temperature. The Ag-NW network is fabricated by H⁺ ion beam-induced welding of Ag-NWs at intersecting positions. H⁺ ion beam induced welding is confirmed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Moreover, the structure of Ag NWs remains stable under H⁺ ion beam, and networks are optically transparent. Morphology also remains stable under H⁺ ion beam irradiation. No slicings or cuttings of Ag-NWs are observed under MeV H⁺ ion beam irradiation. The results exhibit that the formation of Ag-NW network proceeds through three steps: ion beam induced thermal spikes lead to the local heating of Ag-NWs, the formation of simple junctions on small scale, and the formation of a large scale network. This observation is useful for using Ag-NWs based devices in upper space where protons are abandoned in an energy range from MeV to GeV. This high-quality Ag-NW network can also be used as a transparent electrode for optoelectronics devices.