Ethanol purification enables high-quality α-phase FAPbI perovskite microcrystals for commercial photovoltaic applications.

Reliable quality and sustainable processes must be developed for commodities to enter the commercial stage. For next-generation photovoltaic applications such as perovskite solar cells, it is essential to manufacture high-quality photoactive perovskites eco-friendly processes. We demonstrate that ethanol, an ideal green solvent, can be applied to yield efficient alpha-phase FAPbI perovskite microcrystals.

Controlled growth of perovskite layers with volatile alkylammonium chlorides.

Controlling the crystallinity and surface morphology of perovskite layers by methods such as solvent engineering and methylammonium chloride addition is an effective strategy for achieving high-efficiency perovskite solar cells. In particular, it is essential to deposit α-formamidinium lead iodide (FAPbI) perovskite thin films with few defects due to their excellent crystallinity and large grain size. Here we report the controlled crystallization of perovskite thin films with the combination of alkylammonium chlorides (RACl) added to FAPbI.

[Clinical features of acute hepatitis A in recent two years].

Background/aims: The purpose of this study was to characterize the clinical features of acute hepatitis A in Seoul and Gyeonggi province during the recent 2 years.

Methods: We reviewed the medical records of 222 patients who were diagnosed as acute hepatitis A between August 2005 and March 2007 at the Konkuk University Hospital and Korea University, Ansan Hospital. The clinical manifestation, serological tests, and image findings were analyzed.