Disclosed are a hybrid structure using a graphene-carbon nanotube and a perovskite solar cell using the same. The hybrid structure includes a graphene-carbon nanotube formed by laminating a second graphene coated with a polymer on an upper surface of a first graphene coated with a carbon nanotube. The perovskite solar cell includes: a substrate; a first electrode formed on the substrate and including a fluorine doped thin oxide (FTO); an electron transfer layer formed on the first electrode and including a compact-titanium oxide (c-TiO.sub.2); a mesoporous-titanium oxide (m-TiO.sub.2) formed on the electron transfer layer; a perovskite layer formed on the m-TiO.sub.2 and including a perovskite compound; and a graphene-carbon nanotube hybrid structure formed on the perovskite layer.

Described herein is an ink solution, comprising: i. a composition having the formula ABX.sub.3; ii. a compound having the formula NH.sub.2—R.sub.1—NH.sub.2; and iii. a solvent. Methods for producing polycrystalline perovskite films using the ink solutions described herein in a fast blading process and the use of the films in photoactive and photovoltaic applications are additionally described.

Disclosed are a hybrid structure using a graphene-carbon nanotube and a perovskite solar cell using the same. The hybrid structure includes a graphene-carbon nanotube formed by laminating a second graphene coated with a polymer on an upper surface of a first graphene coated with a carbon nanotube. The perovskite solar cell includes: a substrate; a first electrode formed on the substrate and including a fluorine doped thin oxide (FTO); an electron transfer layer formed on the first electrode and including a compact-titanium oxide (c-TiO.sub.2); a mesoporous-titanium oxide (m-TiO.sub.2) formed on the electron transfer layer; a perovskite layer formed on the m-TiO.sub.2 and including a perovskite compound; and a graphene-carbon nanotube hybrid structure formed on the perovskite layer.

Described herein is an ink solution, comprising: i. a composition having the formula ABX.sub.3; ii. a compound having the formula NH.sub.2R.sub.1NH.sub.2; and iii. a solvent. Methods for producing polycrystalline perovskite films using the ink solutions described herein in a fast blading process and the use of the films in photoactive and photovoltaic applications are additionally described.