Photon-enhanced thermionic emission solar cells based on three dimensional graphene aerogel cathode materials

Photon-enhanced thermionic emission (PETE) solar cells are a new type of solar energy conversion device combining the advantages of photovoltaic and thermionic effects. In this paper, three dimensional (3D) graphene aerogel (GA) doped with nitrogen (N) atoms and carbon nanotubes (CNTs) were experimentally used as cathode materials to construct reflection-type PETE solar cells. The cathode materials were prepared by the hydrothermal method in combination with freeze-drying process. The results show that CNTs are randomly distributed in graphene sheets and N atoms are bonded with C atoms, forming a 3D layered structure. Due to the heat and light trappings of the cathode, N-CNTs/GA-based PETE solar cell exhibits the good PETE effect, which short-circuit current is about 11 times higher than that of GA-based device.