%0 Journal Article
%T Benefiting from Spontaneously Generated 2D/3D Bulk©\Heterojunctions in Ruddlesden£¿Popper Perovskite by Incorporation of S©\Bearing Spacer Cation
%A Alireza Honarfar
%A Kaibo Zheng
%A Shuang Yu
%A T£¿nu Pullerits
%A Yajie Yan
%J Archive of "Advanced Science".
%D 2019
%R 10.1002/advs.201900548
%X 2D Ruddlesden¨CPopper (RP) perovskite solar cells have manifested superior operation durability yet inferior charge transport compared to their 3D counterparts. Integrating 3D phases with 2D RP perovskites presents a compromise to maintain respective advantages of both components. Here, the spontaneous generation of 3D phases embedded in 2D perovskite matrix is demonstrated at room temperature via introducing S©\bearing thiophene£¿2£¿ethylamine (TEA) as both spacer and stabilizer of inorganic lattices. The resulting 2D/3D bulk heterojunction structures are believed to arise from the compression©\induced epitaxial growth of the 3D phase at the grain boundaries of the 2D phase through the Pb£¿S interaction. The as©\prepared 2D TEA perovskites exhibit longer exciton diffusion length and extended charge carrier lifetime than the paradigm 2D phenylethylamine (PEA)©\based analogues and hence demonstrate an outstanding power conversion efficiency of 7.20% with significantly increased photocurrent. Dual treatments by NH4Cl and dimethyl sulfoxide are further applied to ameliorate the crystallinity and crystal orientation of 2D perovskites. Consequently, TEA©\based devices exhibit a stabilized efficiency over 11% with negligible hysteresis and display excellent ambient stability without encapsulation by preserving 80% efficiency after 270 h storage in air with 60 ¡À 5% relative humidity at 25 ¡ãC
%K 2D Ruddlesdden¨CPopper perovskites
%K 3D phase
%K air stability
%K low©\temperature fabrication
%K planar solar cells
%U https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6661945/