| Abstract: | We fabricated Sb_2 Se_3 thin film solar cells using tris(8-hydroxy-quinolinato) aluminum(Alq_3) as an electron transport layer by vacuum thermal evaporation.Another small organic molecule of N,N'-bis(naphthalen-1-yl)-N,N'-bis(phenyl)benzidine(NPB) was used as a hole transport layer.We took ITO/NPB/Sb_2Se_3/Alq_3/Al as the device architecture.An open circuit voltage(V_(oc)) of 0.37 V,a short circuit current density(J_(sc)) of 21.2 mA/cm~2,and a power conversion efficiency(PCE) of 3.79% were obtained on an optimized device.A maximum external quantum efficiency of 73% was achieved at 600 nm.The J_(sc),V_(oc),and PCE were dramatically enhanced after introducing an electron transport layer of Alq_3.The results suggest that the interface state density at Sb_2 Se_3/Al interface is decreased by inserting an Alq_3 layer,and the charge recombination loss in the device is suppressed.This work provides a new electron transport material for Sb_2Se_3 thin film solar cells. |
