TY - JOUR
T1 - Deciphering the Role of Water in Promoting the Optoelectronic Performance of Surface-Engineered Lead Halide Perovskite Nanocrystals
AU - Bhatia, Harshita
AU - Martin, Cristina
AU - Keshavarz, Masoumeh
AU - Dovgaliuk, Iurii
AU - Schrenker, Nadine J.
AU - Ottesen, Martin
AU - Qiu, Weiming
AU - Fron, Eduard
AU - Bremholm, Martin
AU - Van de Vondel, Joris
AU - Bals, Sara
AU - Roeffaers, Maarten B.J.
AU - Hofkens, Johan
AU - Debroye, Elke
PY - 2023/2
Y1 - 2023/2
N2 - Lead halide perovskites are promising candidates for high-performance light-emitting diodes (LEDs); however, their applicability is limited by their structural instability toward moisture. Although a deliberate addition of water to the precursor solution has recently been shown to improve the crystallinity and optical properties of perovskites, the corresponding thin films still do not exhibit a near-unity quantum yield. Herein, we report that the direct addition of a minute amount of water to post-treated formamidinium lead bromide (FAPbBr3) nanocrystals (NCs) substantially enhances the stability while achieving a 95% photoluminescence quantum yield in a NC thin film. We unveil the mechanism of how moisture assists in the formation of an additional NH4Br component. Alongside, we demonstrate the crucial role of moisture in assisting localized etching of the perovskite crystal, facilitating the partial incorporation of NH4+, which is key for improved performance under ambient conditions. Finally, as a proof-of-concept, the application of post-treated and water-treated perovskites is tested in LEDs, with the latter exhibiting a superior performance, offering opportunities toward commercial application in moisture-stable optoelectronics.
AB - Lead halide perovskites are promising candidates for high-performance light-emitting diodes (LEDs); however, their applicability is limited by their structural instability toward moisture. Although a deliberate addition of water to the precursor solution has recently been shown to improve the crystallinity and optical properties of perovskites, the corresponding thin films still do not exhibit a near-unity quantum yield. Herein, we report that the direct addition of a minute amount of water to post-treated formamidinium lead bromide (FAPbBr3) nanocrystals (NCs) substantially enhances the stability while achieving a 95% photoluminescence quantum yield in a NC thin film. We unveil the mechanism of how moisture assists in the formation of an additional NH4Br component. Alongside, we demonstrate the crucial role of moisture in assisting localized etching of the perovskite crystal, facilitating the partial incorporation of NH4+, which is key for improved performance under ambient conditions. Finally, as a proof-of-concept, the application of post-treated and water-treated perovskites is tested in LEDs, with the latter exhibiting a superior performance, offering opportunities toward commercial application in moisture-stable optoelectronics.
KW - lead halide perovskites
KW - light-emitting diodes
KW - nanocrystals
KW - passivation
KW - post-treatment
KW - spectroscopy
KW - surface defects
UR - http://www.scopus.com/inward/record.url?scp=85147783515&partnerID=8YFLogxK
U2 - 10.1021/acsami.2c20605
DO - 10.1021/acsami.2c20605
M3 - Journal article
C2 - 36705637
AN - SCOPUS:85147783515
SN - 1944-8244
VL - 15
SP - 7294
EP - 7307
JO - ACS Applied Materials & Interfaces
JF - ACS Applied Materials & Interfaces
IS - 5
ER -