The difficulty of replacing Pb in halide perovskites: Engineering doping strategy to achieve high quality FAPb1-xSrxI3 nanocrystals
by
ANDRÉS FABIAN GUALDRON REYES
Institute of Chemical Sciences, Universidad Austral de Chile, Valdivia, Chile
The substitution of Pb in halide perovskites with less toxic metals is an interesting topic to provide a step forward towards the future commercialization of perovskite -based technologies. However, these materials do not preserve the intrinsic fea-tures of their Pb-based counterparts, giving a dilemma about the convenience of Pb replacement. In this context, it is possible to deduce that the chemical nature of the lead substitute impacts on its own incorporation mechanism into the perov-skite structure, which has not been explored in depth. This seminar will explore the introduction of metal-doping in halide perovskite nanocrystals (PNCs) via the case of FAPbI3 doped by using Sr, this metal being a highly prominent species to replace Pb. Accordingly, the corresponding optical, structural properties and chemical environment of FAPb1−xSrxI3 PNCs will be explored as a function of the capability of Sr2+ to substitute Pb2+. The replacement of Pb by a low Sr content (~7 at%) allows FAPb1−xSrxI3 PNCs to be obtained with improved intrinsic properties, better deep red color quality, and long-term stability for 8 months under a relative humidity of 40–50%. This stability feature is one of the highest values reported for halide PNCs under air ambient conditions. Nevertheless, in an at-tempt to increase the Sr content in PNCs, a mixture of 2D nanoplatelets/3D nanocubes is obtained as the final product, caused by a high Pb deficiency during the FAPb1−xSrxI3 synthesis. This contribution gives a novel insight to understand how the suitable/poor Pb substitution achieved through Sr-doping dictates the photophysical properties of PNCs, giving a clear explanation about the require-ments that the promising metal substitute has to present to eventually favor the replacement of Pb. Finally, some characteristics about the color quality and po-tential application in optoelectronics and photocatalysis will be highlighted.
It is our pleasure to invite you to join the ISGS eSeminar for September 2023, which will be delivered by Dr Andrés Reyes on Thursday 28 September. Andrés is a researcher at the Institute of Chemical Sciences at the Universidad Austral de Chile in Valdivia, Chile. His major research focus is on the design, synthesis and applications of perovskites in applica-tions such photovoltaics, light-emitting diodes,
Date: Thursday 28 September 2023
Format:
- ZOOM (eSeminar link), Meeting ID: 307 291 6432 Passcode: 3+VD84eS
Time:
- 08:00 – Ottawa, USA, East Coast
- 09:00 – Brazil (São Paulo) and Argentina
- 12:00 – UTC
- 13:00 – UK, Portugal
- 14:00 – Central Europe, Sweden, Norway, Switzerland
- 15:00 – Romania, Israel, Eastern Europe, Ukraine
- 15:00 – Russia (Moscow, St Petersburg)
- 20:00 – China, Singapore, Malaysia
- 21:00 – Japan, Korea
- 22:00 – Australia (East Coast)
