Graphene for switchable flexible smart windows application

Here, we designed a flexible, high-performance, foldable, and very simple -to -design electrochromic device (ECD) by using wide-area multi-layer graphene (MLG) as an electrode. ML-graphene samples were synthesized by chemical vapor deposition method (CVD); Electrical, optical, and structural characterization was performed. Following this, MLG films were transferred onto polyethylene using the water bath method, which is a very cheap and simple transfer method, and the electrochromic device design was carried out. As a result of optical measurements, it was seen that the optical transmittance value increased starting from the threshold voltage of 2.8 V and there was a change of approximately 40 % at 5 V. When the Raman spectrum of ML-graphene samples is examined, there is a distinct G peak at 1567 cm - 1 and the band position shifts to lower energy levels depending on the increasing number of layers. According to the data obtained from X-ray diffraction (XRD) spectroscopy used for structural characterization, it was concluded that p-type doping is easier than n-type and occurs at lower voltage values. Additionally, in the switching time analysis, it is seen that the time taken for the intercalation process is longer than the time for the deintercalation process.