Hybrid graphene/amorphous carbon films with tadpole-like structures for high-performance photovoltaic applications

Hybrid graphene/amorphous carbon (G/a-C) films with tadpole-like agglomerates were prepared by chemical vapor deposition using ethanol as the precursor. The agglomerates have a quasi 1-D nanostructure with a height of 30–100 nm, width of ∼50 nm and length of ∼1 μm. A Schottky junction solar cell was assembled by transferring as-synthesized G/a-C films onto n-Si, showing a power conversion efficiency of 3.66%. The remarkable cell efficiency can be attributed to the tadpole-like agglomerates, which could act as a direct path for charge transport. The cell efficiency could be further enhanced to 6.07% by HNO3 treatment of the G/a-C films, demonstrating their potential applications in carbon-based photovoltaic devices.