This article presents the investigation on very thin Lanthanum Fluoride (LaF3) layer as a new cathode buffer layer (CBL) for organic solar cell (OSC). OSCs were fabricated with poly(3-hexylthiophene) (P3HT) and phenyl...This article presents the investigation on very thin Lanthanum Fluoride (LaF3) layer as a new cathode buffer layer (CBL) for organic solar cell (OSC). OSCs were fabricated with poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) polymer blend at 1:1 ratio. Electron-beam evaporation at room temperature was used to deposit 3 and 5 nm thick LaF3 layer. A very smooth surface of LaF3 with an average roughness of 0.2 nm has been observed by the Atomic Force Microscope (AFM) that is expected to prevent diffusion of cathode metal ion through it and thereby enhance the lifetime and stability of OSC. Huge enhancement of JSC and VOC was also observed for 3 nm-thick LaF3 CBL. Several excellent features of the LaF3 layer such as, transporting electron through tunneling, blocking of holes to the cathode, minimizing recombination, protecting the photoactive polymer from ambient oxygen, and reducing degradation/oxidation of any low work function layer at the cathode interface, might have contributed to the performance enhancement of OSC. The experimental findings indicate the promise of LaF3 to be an excellent CBL material for OSC.展开更多
文摘This article presents the investigation on very thin Lanthanum Fluoride (LaF3) layer as a new cathode buffer layer (CBL) for organic solar cell (OSC). OSCs were fabricated with poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) polymer blend at 1:1 ratio. Electron-beam evaporation at room temperature was used to deposit 3 and 5 nm thick LaF3 layer. A very smooth surface of LaF3 with an average roughness of 0.2 nm has been observed by the Atomic Force Microscope (AFM) that is expected to prevent diffusion of cathode metal ion through it and thereby enhance the lifetime and stability of OSC. Huge enhancement of JSC and VOC was also observed for 3 nm-thick LaF3 CBL. Several excellent features of the LaF3 layer such as, transporting electron through tunneling, blocking of holes to the cathode, minimizing recombination, protecting the photoactive polymer from ambient oxygen, and reducing degradation/oxidation of any low work function layer at the cathode interface, might have contributed to the performance enhancement of OSC. The experimental findings indicate the promise of LaF3 to be an excellent CBL material for OSC.
