Multidentate Zwitterionic Ligand-Assisted Formation of Pure Bromide-Based Perovskite Nanosheets and Their Application in Blue Light-Emitting Diodes

Abstract

Perovskite light-emitting diodes (PeLEDs) have demonstrated rapid development during the past decade, whereas the inferior device performance of blue ones impedes the application in full-color display and lighting. Low-dimensional perovskites turn out to be the most promising blue-emitters owing to their superior stability. In this work, a multidentate zwitterionic l-arginine is proposed to achieve blue emission from pure bromide-based perovskites by in situ-forming low-dimensional nanosheets. First, l-arginine can promote the formation of perovskite nanosheets due to the strong interaction between the peripheral guanidinium cations and [PbBr6]4– octahedral layers, enabling a significant blue-shift. Second, the carboxyl group within l-arginine can passivate uncoordinated Pb2+ ions, improving the device performance. Finally, a blue PeLED is successfully constructed on the basis of the l-arginine-modulated perovskite film, demonstrating a peak luminance of 2152 cd/m2, an external quantum efficiency of 5.4%, and operation lifetime of 13.81 min. Further, the enlightenment from this work is hopefully to be applied in rationally designing spacer cations for low-dimensional perovskite optoelectronic devices.

Recent advance of high-quality perovskite nanostructure and its application in flexible photodetectors

“…Furthermore, the carboxyl group in L-arginine effectively passivated the uncoordinated Pb 2+ ions. As a result, the blue LED with L-arginine-additive displayed a peak luminance of 2152 cd m −2 and an EQE of 5.4% (figure 8(d)) [115].…”

“…The preparation of 3D perovskite polycrystalline films primarily employs low-temperature solution processes and chemical vapor deposition methods. Among them, the one-step spin-coating stands out as the most straightforward, wherein the perovskite precursor swiftly crystallizes directly onto the substrate during rapid rotation [69,[115][116][117][118][119][120].…”