tailieunhanh - báo cáo hóa học:" Hafnium metallocene compounds used as cathode interfacial layers for enhanced electron transfer in organic solar cells Keunhee Park1, Se"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Hafnium metallocene compounds used as cathode interfacial layers for enhanced electron transfer in organic solar cells Keunhee Park1, Se | Park et al. Nanoscale Research Letters 2012 7 74 http content 7 1 74 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access Hafnium metallocene compounds used as cathode interfacial layers for enhanced electron transfer in organic solar cells Keunhee Park1 Seungsik Oh1 Donggeun Jung1 Heeyeop Chae2 Hyoungsub Kim3 and Jin-Hyo Boo4 Abstract We have used hafnium metallocene compounds as cathode interfacial layers for organic solar cells OSCs . A metallocene compound consists of a transition metal and two cyclopentadienyl ligands coordinated in a sandwich structure. For the fabrication of the OSCs poly 3 4-ethylenedioxythiophene poly styrene sulfonate poly 3-hexylthiophene-2 5-diyl 6 6 -phenyl C61 butyric acid methyl ester bis- ethylcyclopentadienyl hafnium IV dichloride and aluminum were deposited as a hole transport layer an active layer a cathode interfacial layer and a cathode respectively. The hafnium metallocene compound cathode interfacial layer improved the performance of OSCs compared to that of OSCs without the interfacial layer. The current density-voltage characteristics of OSCs with an interfacial layer thickness of nm and of those without an interfacial layer showed power conversion efficiency PCE values of and respectively under an illumination condition of 100 mW cm2 AM . It is thought that a cathode interfacial layer of an appropriate thickness enhances the electron transfer between the active layer and the cathode and thus increases the PCE of the OSCs. Keywords organic solar cell cathode interfacial layer metallocene compounds. Introduction Organic solar cells OSCs have attracted attention due to their unique advantages such as easy processing low cost of fabrication of large-area cells and mechanical flexibility 1 . However the efficiency of organic solar cells is not sufficient for them to be used commercially. Therefore many methods such as treatment and annealing have been proposed .