Graphene film

Characterization of graphene films and transistors grown on sapphire by metal-free chemical vapor deposition, ACS Nano, 5 (2011) 8062-8069. 

Gas phase approaches have the advantage that the nanocarbons do not need to be filtered or washed after hybridization making them ideal for nanocarbons produced on substrates such as CVD grown graphene films or CNT forests which tend to lose their structure upon immersion and/or drying. Consequently they are not ideal for chemically modified GO or CNTs. 

Graphene films are promising candidates as electrodes in OLED devices as transparent anodes and cathodes. However, optimization of graphene film characteristics (thickness and quality) is necessary in order to obtain device results comparable to ITO based devices [254, 260]. 

Fig. 32 (a) Energy level diagram, (b) Four layers from bottom to top are Au, dye-sensitized heterojunction, compact T102, and graphene film. (Reprinted with permission from [267])... 

In DSSCs, graphene incorporation into electrode composites increases the overall energy conversion efficiency by up to five times. Nonetheless, further research is in order to optimize the construction and characteristics of graphene based devices (e.g., graphene film thickness and amount, device fabrication conditions, and configuration) [267, 270]. 

Mullen et al. in 2008 reported the successful use of graphene films (TGF) as transparent electrodes (anodes) in BHJ solar cells composed of P3HT and PCBM as the active layer (see Fig. 34) [258]. The cell conversion efficiency under low intensity monochromatic light showed the same values as the ITO electrode (1.5%) and under simulated solar light the values were lower (0.29%) compared to the obtained values for ITO (1.17%) under the same conditions. Although the study under simulated solar light was not satisfactory, the BHJ solar cell shows promise for the use of graphene in this type of devices after further optimization of the cell. 

Kim KS, Zhao Y, Jang H et al (2009) Large-scale pattern growth of graphene films for stretchable transparent electrodes. Nature 457 706-710... 

Gomez De Arco L, Zhang Y, Schlenker CW et al (2010) Continuous, highly flexible, and transparent graphene films by chemical vapor deposition for organic photovoltaics. ACS Nano 4 2865-2873... 

Yu A, Roes 1, Davies A et al (2010) Ultrathin, transparent, and flexible graphene films for supercapacitor application. Appl Phys Lett 96 253105... 

Wu JB, Becerril HA, Bao ZN, Liu ZF, Chen YS, Penmans P (2008) Organic solar cells with solution-processed graphene transparent electrodes. Appl Phys Lett 92 263302 De Arco LG, Zhang Y, Schlenker CW, Ryu K, Thompson ME, Zhou CW (2010) Continuous, highly flexible, and transparent graphene films by chemical vapor deposition for organic photovoltaics. Acs Nano 4 2865... 

Li XS, Zhu YW, Cai WW, Borysiak M, Han BY, Chen D, Piner RD, Colombo L, Ruoff RS (2009) Transfer of large-area graphene films for high-performance transparent conductive electrodes. Nano Lett 9 4359... 

Latil S, Henrard L (2006) Charge carrier in few-layer graphene films. Phys Rev Lett 97 036803... 

Varchon F, Mallet P, Magaud L, Veuillen J-Y (2008) Rotational disorder in few-layer graphene films on 6H-SiC(000-l) a scanning tunneling microscopy study. Phys Rev B 77 165415... 

Reina, A., Jia, X., Ho, J., Nezich, D., Son, H., Bulovic, V., Dresselhaus, M. S. and Kong, J. (2008), Large area, few-layer graphene films on arbitrary substrates by chemical vapor deposition. Nano Letters, 9,30-5. 

Davies, A., Audette, R, Farrow, B., Hassan, R, Chen, Z., Choi, J., and Yii, A (2011). Graphene-based flexible supercapacitors Pulse-electropotymerization of pol3 yrrole on free-standing graphene films,/ Phys. Chem. C, 115, pp. 17612-17620. 

Siju, C., Raja, L., Shivaprakash, N., and Sindhu, S. (2015). Gray to transmissive eiectrochromic switching based on electropolymerized REDOT-ionic liquid functionalized graphene films, J. Solid State Electrochem, pp. 1-10. 

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