Incorporating Zirconium-Based Metal-Organic Frameworks into Hole Transport Layer for Efficient Organic-Inorganic Solar Cells

Abstract

Metal-organic frameworks (MOFs), which are porous coordination polymers exhibiting long-range ordered metal clusters connected with organic linkers, have been studied actively due to their potentials for various applications such as gas separation, drug delivery, catalysis and chemical sensing. There are some of reports expecting that MOFs could be utilized to electronics, but a few reports regarding to MOF-included electronics have also appeared. Among them, organic-inorganic solar cells have risen as promising candidates for photovotaics (PVs) owing to their superior properties such as effective cost, and use of renewable power source. In order to obtain higher power conversion efficiency of PV devices, the suitable engineering of buffer layer as well as that of active layer is needed. Herein, we reported the application of zirconium-based MOFs to hole transport layer in PV devices. Brushing method from precursor solution under hot-substrate condition was employed to build the thin MOFs films, incorporated into PV devices. By this straightforward strategy, the transparent and thin MOF films converted from precursor solution were deposited, development of films and electronic properties of those were analyzed by photoelectron spectroscopy in air (PESA) and found to be appropriate for charge injection and transfer between active and MOF layer. This result indicates that the brushing method could be a promising candidate for preparing MOF films to be able to fabricate MOF-combined electronics.