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Due to the high abundance of copper on the earth and its high intrinsic electrical conductivity, copper nanowires (CuNWs) represent a promising material for transparent electrodes. In this work, an environmentally friendly and scalable synthesis that requires a low process temperature is studied. The optimum temperature is found at 79 °C, which results in nanowires with the lowest diameters. The as‐synthesized solution is sprayed to transparent conducting films, which are in turn subjected to various post‐treatments such as thermal sintering or washing with propionic acid to enhance their electro‐optical performance. Following both the optimum protocol for the synthesis and post‐treatment, a sheet resistance of 10.3 Ω ◻−1 at a transparency of 83.4% is achieved. Moreover, the CuNW‐films are tested as transparent heaters and show a homogeneous heat distribution. For the electrical properties of the films, a temperature dependence of resistance that is lowered around 28% compared to the one for bulk copper is found.

Grain boundaries, inevitably present in chemical vapor deposited graphene, are expected to have considerable impact on the development of graphene-based hybrid materials with tailored material properties. We here demonstrate the critical role of polycrystallinity on the chemical functionalization of graphene comparing ozone-induced oxidation with remote plasma hydrogenation. We show that graphene oxidation and hydrogenation occur in two consecutive stages upon increasing defect density: an initial step in which surface-bound functional groups are generated, followed by the creation of vacancies. Remarkably, we find that hydrogenation yields homogeneously distributed defects while ozone-induced defects are preferentially accumulated at the grain boundaries eventually provoking local cracking of the structure. Supported by quantum simulations, our experimental findings reveal distinct electronic transport regimes depending on the density and distribution of

n this study, we investigate the infrared and electrical propertiesas well as the thermal response of transparent silvernanowire (AgNW) based thin-film heaters, when subjected toJoule heating. Controlling the number of layers and hence thedeposition time, our spray-coating technique allows to modulatethe thermal and electrical properties of the thin films in a precisemanner. In addition, this technique enables the fabrication ofhomogeneous and large-area heaters, which, in terms of theirelectro-optical properties, nicely compare to the performances ofstate-of-the-art AgNW transparent electrodes. The thermal response and the electrical properties are accurately reproducedby a purposely developed physical model, which shows that thetemperature dependence of the AgNW film resistance is loweredby a factor of 2 compared to bulk silver, independently of thenumber of deposited layers. Compared to uncoated glass,the emissivity decreases by 58% at a coverage rate of 58%. At thesame time, the AgNW film can sustain a transparency as high as81.3%. Therefore, AgNW-based thin films can be used as a low-emissivity coating, for e.g., energy-efficient window glazingapplications. Finally, we accurately determine the fragmentationtemperature of AgNWs, which sets the ultimate limitation of usefor heating applications