Enhanced hole extraction by interaction between CuI and MoO3 in the hole transport layer of organic photovoltaic devices. - Yoon, Sangcheol; Kim, Hyebin; Shin, Eul-Yong; Bae, In-Gon; Park, Byoungchoo; Noh, Yong-Young; Hwang, Inchan (Organic Electronics, 2016)