Assembly Of Ultrathin Gold Nanowires Into Films With High Transparency And Conductivity

Honeycomb macroporous pattern(HMP)film has attracted extensive attention,because it has promising properties and can be used in diversified fields such as superhydrophobic coating,cell culture,sensors and optoelectronic devices.So far,there are several methods to prepare HMP film with artificial nanomaterials.Nonetheless,these methods need templates or supermolecule/polymer/surfactant assistant.A convenient colloidal template-free method to prepare pure metal HMP film has not been reported.In this thesis,we have presented a simple template-free approach for preparation of ultrathin gold HMP film with high transparency and conductivity.Because of its linear polymer-like morphology,ultrathin gold nanowires can be assembled into HMP film on different substrates,using a traditional static breath figure method.Subsequently,we adopted chemical crosslinking and oxygen plasma treatment are used to enhance the stability and conductivity of the ultrathin gold HMP film.The main findings are as follows:1.Synthesis of Au nanowires:The ultrathin gold nanowires can be obtained in tetrahydrofuran(THF)with HAuCl4·3H2O as ingredient,oleylamine(OM)as stabilizer and triisopropylchlorosilane(TIPS)as reductant.The diameter of Au NWs synthesized is around 2 nm and the length can be controlled by adding different amount of water.2.Preperation of HMP film:The ultrathin gold HMP film can be prepared on different substrates by static BF method.And the film has the height between 200 and 300 nm,and the average size of each pore is 4.75 ± 0.79 μm.The influence of different factors on the morphology of the ultrathin gold HMP film is investigated and the result indicates that the mechanism is fairly in agreement with that in typical polymeric BF film.3.Postprocessing of HMP film:After crosslinked with hydrogen peroxide and treated by oxygen Plasma,the gold NWs HMP film has low surface resistance as 125 Ω/sq.The high conductivity is attributed to the fusion of inter-NW and removal of packed OA on the surface of Au NWs.4.Transparent and conductive electrode of HMP film:Au NWs HMP films on glass slice and Teflon slice have low sheet resistance as 210 Ω/sq and 159 Ω/sq and high optical transmittance as 87.7%and 93.2%,respectively.Then a circuit of a LED light,a battery and the film on Teflon is set up,and the LED light can be continuously lighting regardless of what deformation happens to the film,bent and stretched included.Furthermore,the sheet resistance of the film on Teflon only changes a little even after bent for 1000 cycles.The results suggest that the ultrathin gold HMP film prepared by BF method has highly stable conductivity even under mechanical deformation,which has a great potential for transparent,conductive and flexible nanodevices.