▎ 摘 要
Direct growth of graphene on Al2O3 film is successfully achieved assisted with NiAl2O4 film on a SiO2 substrate by chemical vapor deposition at 800 degrees C. The Ni particles are first uniformly separated out on the substrate, and play an important role in capturing carbon atoms and accelerating the nucleation to grow high quality graphene rooting on insulating Al2O3 film. The thickness of graphene films can be tuned from two layers to few layers (<10) by changing growth time. The continuous graphene films exhibit extremely excellent electrical transport properties with a sheet resistance of down to 18.5 Omega sq(-1). The graphene/Ni/Al2O3/SiO2 is used as the counter electrode of dye sensitized solar cell which achieves a photovoltaic efficiency of 7.62%. (C) 2014 Elsevier Ltd. All rights reserved.