Room-Temperature Surface Modification of Cu Nanowires and Their Applications in Transparent Electrodes, SERS-Based Sensors, and Organic Solar Cells.

Cu nanowires (Copper nanowires) have attracted lots of attention recently due to their potential applications in transparent electrodes, surface enhanced Raman scattering (SERS) based sensors, and solar cells. However, as the surface composition and morphology of Cu nanowires severely influence the performance of the devices based on them, facile surface modification methods need to be developed. Herein, we propose a room-temperature, time-saving aqueous solution method, through which clean Cu nanowires with small Ag nanoparticles decorating around them could be achieved. The unique "sesame candy bar" structure of Cu nanowires brought about significant enhancement on the electrical, optical, and mechanical performances of Cu nanowire networks. Transparent electrodes with ideal opto-electrical performance (47 Ω sq @ 89.1% T) and high antioxidation, antithermal, and electrical stability were fabricated. Stretchable electrodes based on the modified Cu nanowire networks showed superior stretch-ability and cyclic stability. SERS sensors and organic solar cells based on Cu nanowire networks exhibited high performance due to the enhanced surface plasmonic coupling and light scattering effect. We believe that the method will shed light on the large-scale fabrication and application of Cu nanowire based devices.