Photostability and photodegradation process in colloidal CsPbI3 quantum dots
(2018) KEMP39 20181Department of Chemistry
- Abstract
- All-inorganic CsPbI3 perovskite quantum dots (QDs) have attracted intense attention for the application in photovoltaics and optoelectronic applications due to their phase stability and great photoluminescence (PL) properties. However, the their photostability is still to be investigated in detail. In this thesis work, we studied the photostability of the CsPbI3 QDs suspended in hexane and found light illumination would induce photodegradation of CsPbI3 QDs. The steady-state spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and transient-absorption spectroscopy (TA) verified that light illumination would lead to the collapse of the CsPbI3 QDs’surface and the... (More)
- All-inorganic CsPbI3 perovskite quantum dots (QDs) have attracted intense attention for the application in photovoltaics and optoelectronic applications due to their phase stability and great photoluminescence (PL) properties. However, the their photostability is still to be investigated in detail. In this thesis work, we studied the photostability of the CsPbI3 QDs suspended in hexane and found light illumination would induce photodegradation of CsPbI3 QDs. The steady-state spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and transient-absorption spectroscopy (TA) verified that light illumination would lead to the collapse of the CsPbI3 QDs’surface and the emergence of Pb0, which is a trapped state leading to the quench of PL and dramatic decrease of quantum yield. Our work provides some insight of the photodegradation process in CsPbI3 QDs and could lead to the optimization of such QDs towards device applications. (Less)
- Popular Abstract
- Nowadays, we demand a huge amount of energy due to population growth and rising living standards. A substantial portion of our energy consumption is from fossil fuels (i.e. coal, oil and natural gas), that would lead to environmental pollution and global warming which are serious problems. As a suitable alternative, solar energy is renewable, clean, and cheap. It is a key to find high-performance materials to harvest and use solar energy efficiently.
Many materials have been investigated towards solar cell applications. In this thesis, we are giong to study one particular type of material, lead halide perovskites. In recent years, they have attracted intense attention in various photovoltaics and optoelectronic applications such as solar... (More) - Nowadays, we demand a huge amount of energy due to population growth and rising living standards. A substantial portion of our energy consumption is from fossil fuels (i.e. coal, oil and natural gas), that would lead to environmental pollution and global warming which are serious problems. As a suitable alternative, solar energy is renewable, clean, and cheap. It is a key to find high-performance materials to harvest and use solar energy efficiently.
Many materials have been investigated towards solar cell applications. In this thesis, we are giong to study one particular type of material, lead halide perovskites. In recent years, they have attracted intense attention in various photovoltaics and optoelectronic applications such as solar cells and light-emitting diodes (LEDs) due to their great photophysical properties. While the photophysical properties in lead halide perovskite materials are very important to improve the performance of the materials and devices, to understand their photostability is also a key to realize mass application. In this thesis, we studied the photostability of one lead halide perovskite material, the CsPbI3 quantum dots (QDs are very small semiconductor particles, usually under 20 nanometres in size, 1 nm = 10−9 m) because of their high efficiency in solar cells. We also investigated the photodegradation process, i.e. what would happen and how the QDs would change upon light illumination. We find that upon illumination, some lead would emerge on the surface of the QDs, that would significantly lower its photoluminescent properties. This knowledge may be useful for optimization of such QDs towards device applications. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/8954384
- author
- An, Rui LU
- supervisor
-
- Kaibo Zheng LU
- organization
- course
- KEMP39 20181
- year
- 2018
- type
- L3 - Miscellaneous, Projetcs etc.
- subject
- keywords
- Light illumination, trap state, blue-shift emission, quantum yield drop, surface collapse, photodegradation mechanism, chemical physics, kemisk fysik
- language
- English
- id
- 8954384
- date added to LUP
- 2018-09-25 11:18:26
- date last changed
- 2018-09-25 11:18:26
@misc{8954384,
abstract = {{All-inorganic CsPbI3 perovskite quantum dots (QDs) have attracted intense attention for the application in photovoltaics and optoelectronic applications due to their phase stability and great photoluminescence (PL) properties. However, the their photostability is still to be investigated in detail. In this thesis work, we studied the photostability of the CsPbI3 QDs suspended in hexane and found light illumination would induce photodegradation of CsPbI3 QDs. The steady-state spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and transient-absorption spectroscopy (TA) verified that light illumination would lead to the collapse of the CsPbI3 QDs’surface and the emergence of Pb0, which is a trapped state leading to the quench of PL and dramatic decrease of quantum yield. Our work provides some insight of the photodegradation process in CsPbI3 QDs and could lead to the optimization of such QDs towards device applications.}},
author = {{An, Rui}},
language = {{eng}},
note = {{Student Paper}},
title = {{Photostability and photodegradation process in colloidal CsPbI3 quantum dots}},
year = {{2018}},
}