Passivation,as a classical surface treatment technique,has been widely accepted in start-of-the-art perovskite solar cells(PSCs)that can effectively modulate the electronic and chemical property of defective perovskit...Passivation,as a classical surface treatment technique,has been widely accepted in start-of-the-art perovskite solar cells(PSCs)that can effectively modulate the electronic and chemical property of defective perovskite surface.The discovery of inorganic passivation compounds,such as oxysalts,has largely advanced the efficiency and lifetime of PSCs on account of its favorable electrical property and remarkable inherent stability,but a lack of deep understanding of how its local configuration affects the passivation effectiveness is a huge impediment for future interfacial molecular engineering.Here,we demonstrate the central-atom-dependent-passivation of oxysalt on perovskite surface,in which the central atoms of oxyacid anions dominate the interfacial oxygen-bridge strength.We revealed that the balance of local interactions between the central atoms of oxyacid anions(e.g.,N,C,S,P,Si)and the metal cations on perovskite surface(e.g.,Pb)generally determines the bond formation at oxysalt/perovskite interface,which can be understood by the bond order conservation principle.Silicate with less electronegative Si central atoms provides strong O-Pb motif and improved passivation effect,delivering a champion efficiency of 17.26%for CsPbI2Br solar cells.Our strategy is also universally effective in improving the device performance of several commonly used perovskite compositions.展开更多
基金Ze Qing Lin and Hui Jun Lian contributed equally to this work.This work was financially supported by National Natural Science Fund for Excellent Young Scholars(52022030)International(Regional)Cooperation and Exchange Projects of the National Natural Science Foundation of China(51920105003)+4 种基金National Natural Science Fund for Distinguished Young Scholars(51725201)National Ten Thousand Talent Program for Young Top-notch Talent,National Natural Science Foundation of China(51902185,51972111)Innovation Program of Shanghai Municipal Education Commission(E00014)Shanghai Engineering Research Center of Hierarchical Nanomaterials(18DZ2252400)The authors also thank the Frontiers Science Center for Materiobiology and Dynamic Chemistry.
文摘Passivation,as a classical surface treatment technique,has been widely accepted in start-of-the-art perovskite solar cells(PSCs)that can effectively modulate the electronic and chemical property of defective perovskite surface.The discovery of inorganic passivation compounds,such as oxysalts,has largely advanced the efficiency and lifetime of PSCs on account of its favorable electrical property and remarkable inherent stability,but a lack of deep understanding of how its local configuration affects the passivation effectiveness is a huge impediment for future interfacial molecular engineering.Here,we demonstrate the central-atom-dependent-passivation of oxysalt on perovskite surface,in which the central atoms of oxyacid anions dominate the interfacial oxygen-bridge strength.We revealed that the balance of local interactions between the central atoms of oxyacid anions(e.g.,N,C,S,P,Si)and the metal cations on perovskite surface(e.g.,Pb)generally determines the bond formation at oxysalt/perovskite interface,which can be understood by the bond order conservation principle.Silicate with less electronegative Si central atoms provides strong O-Pb motif and improved passivation effect,delivering a champion efficiency of 17.26%for CsPbI2Br solar cells.Our strategy is also universally effective in improving the device performance of several commonly used perovskite compositions.
