Optimization of organic photovoltaic devices using tuned mixed metal oxide contact layers

The use of oxide materials as a hole transport layers (HTL) offers the opportunity to optimize hole collection in a bulk heterojunction organic photovoltaic (OPV) device. We discuss the use of NiO
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deposited by three different methods, pulsed laser deposition, sputtering and a solution precursor as an alternative to the standard OPV HTL. We also examine the ability of the HTL to improve device performance in a bulk heterojunction device utilizing a donor that has a deeper highest occupied molecular orbital (HOMO) level‥