Functional silver nanowires

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2018
Alpuğan, Ece
Silver nanowires (Ag NWs) are one of the most promising nanomaterials for future optoelectronic devices. They have high thermal and electrical conductivity and high transparency in network form, which are the key properties for various applications. The use of Ag NWs have been demonstrated in heaters, photodetectors and biosensors. In this thesis, firstly, Ag NW networks are used as electromagnetic interference shields on different substrates such as polyethylene terephthalate (PET), textile, filter paper and felt. Ag NWs are spray coated onto PET substrates, while dip coating method is used for filter paper, textiles and felt substrates. Maximum shielding is obtained with the Ag NW coated filter paper sample with a resistance of 10 ohm. Almost 99 % shielding is observed. Secondly, Ag NWs are used as top and bottom electrodes for organic solar cells. For bottom electrodes, Ag NWs are spray coated onto glass substrates. The device structure for these solar cells is Ag NW/PEDOT: PSS/P3HT: PCBM/ LiF /Al. A control sample was fabricated on commercially available indium tin oxide (ITO) thin films. A power conversion efficiency of 1.13 % is obtained from vi solar cells with Ag NW bottom electrodes, while a conversion efficiency of 3.15 % is obtained from ITO control sample. For top electrodes in inverted solar cell structure, Ag NWs on polydimethylsiloxane (PDMS) substrates are used and simply placed onto fabricated devices. The device structure for these solar cells is ITO/ZnO/P3HT:PCBM/PEDOT:PSS/Ag NW-PDMS. A control device with gold top electrode is also fabricated. A power conversion efficiency of 1.73 % is obtained for top electrode devices, while that for the control device is 2.62 %. It is worth mentioning that these top electrode devices are partially transparent. All in all, very promising characteristics are obtained using Ag NWs both in electromagnetic interference shields and in organic solar cells as electrodes.
Citation Formats
E. Alpuğan, “Functional silver nanowires,” M.S. - Master of Science, Middle East Technical University, 2018.