Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics, Jan 2020, Tsukuba-shi, Japan Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics, Jan 2020, Tsukuba-shi, Japan.