A magic molecular binder for stable efficient perovskite solar cells

Durability has been the major obstacle, if not the Achilles' heel, for commercializing metal halide perovskite solar cells (PSCs), and the culprit is chiefly the point defects of undercoordinated lead atoms at interfaces and grain boundaries. A recent work published in Science by Yan et al. features a Lewis base diphosphine molecule of 1,3-bis(diphenylphosphino)propane, which can effectively passivate the Lewis-acidic undercoordinated lead atoms and simultaneously stitch and bond the interfaces and grain boundaries, thereby remarkably enhancing the durability of PSCs.