Solution-based synthesis of silver-platinum core-shell nanowires with enhanced stability

Koylan, Serkan
This work describes a facile route for the synthesis of silver (Ag)-platinum (Pt) core-shell nanowires (NWs) with controlled diameter in the range of 63-96 nm. Optimum synthesis conditions were determined to obtain conformal and galvanic replacement free deposition of Pt on Ag NWs. Synthesized Ag-Pt core-shell NWs were examined using SEM, TEM and XPS. Further studies were conducted to compare the performances of Ag-Pt core-shell NW networks to those of pristine Ag NW networks. In this regard, electrochemical, chemical and environmental stabilities were elaborated. Electrochemical stability tests were conducted in three electrode configuration comprised of Ag/AgCl reference, Pt plate counter and nanowire network working electrodes. In chemical stability tests, resistance change upon hydrogen peroxide exposure was monitored. The environmental stability tests were carried out under different relative humidity levels and temperatures. The humidity levels and temperatures were selected as 43, 75 and 84 %RH and 150 oC, 75 oC and room temperature, respectively. In all cases, clear improvement of stability for Ag-Pt core-shell NW networks were obtained. All in all, this highly effective and simple strategy to improve the stability vi of Ag NWs will certainly open new avenues for their large scale utilization in various optoelectronic devices.


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Citation Formats
S. Koylan, “Solution-based synthesis of silver-platinum core-shell nanowires with enhanced stability,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Metallurgical and Materials Engineering., Middle East Technical University, 2019.