Lead Acetate Assisted Interface Engineering for Highly Efficient and Stable Perovskite Solar Cells
Zhang, Ma, Shin, Jung, Lee, Wu, Jeong, Lee, Kim, Kim, Park (2020) Lead Acetate Assisted Interface Engineering for Highly Efficient and Stable Perovskite Solar Cells ACS Appl Mater Interfaces (IF: 9.5) 12(6) 7186-7197Abstract
High power conversion efficiency (PCE) and long-term stability are inevitable issues faced in practical device applications of perovskite solar cells. In this paper, significant enhancements in the device efficiency and stability are achieved by using a surface-active lead acetate (Pb(OAc)2) at the top or bottom of CH3NH3PbI3 (MAPbI3)-based perovskite. When a saturated Pb(OAc)2 solution is introduced on the top of the MAPbI3 perovskite precursor, the OAc- in Pb(OAc)2 participates in lattice restructuring of MAPbI3 to form MAPbI3-x(OAc)x, thereby producing a high-quality perovskite film with high crystallinity, large grain sizes, and uniform and pinhole-free morphology. Moreover, when Pb(OAc)2 solution is mixed in the poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS) solution in the bottom way, the OAc- in Pb(OAc)2 improves the water resistance of PEDOT-PSS. As the OAc- easily bonds with the Pb2+, the deposition of MAPbI3 precursor onto the Pb(OAc)2 mixed with PEDOT-PSS results in a reduction of the uncoordinated Pb, leading to strong stabilization of the perovskite layer. Both the top- and bottom-treated devices exhibit enhanced PCE values of 18.93% and 18.28%, respectively, compared to the conventional device with a PCE of 16.47%, which originates from decreased trap sites and reduced energy barriers. In particular, the bottom-treated device exhibits long-term stability, with more than 84% of its initial PCE over 800 h in an ambient environment.
Links
http://www.ncbi.nlm.nih.gov/pubmed/31944647http://dx.doi.org/10.1021/acsami.9b19691
