Emergence of Photoluminescence in Cs4CuSb2Cl12 under Ambient and High Pressure Conditions

Shukla, Aditya (2021) Emergence of Photoluminescence in Cs4CuSb2Cl12 under Ambient and High Pressure Conditions. Masters thesis, Indian Institute of Science Education and Research Kolkata.

Text (MS Dissertation of Aditya Shukla (16MS087)) 16MS087_Thesis_file.pdf - Submitted Version Restricted to Repository staff only Download (2MB)

Abstract

Halide perovskites have shown some tremendous growth in efficiencies from 3.8% to 25.6 % in a short span of 12 years. Although these materials rival the efficiencies of industry standard silicon solar cells, challenges like stability and toxicity have not been resolved yet. Researchers have discovered a novel stable and non-toxic perovskite called the vacancy ordered layered double perovskite. In this work we have worked with the Cs4CuSb2Cl12 perovskite phase to improve its optoelectronic properties with major focus on its photoluminescence emission. We could transform this non-emissive material in the form of nanocrystals into a visible light emitting material using a modified hot-injection synthesis method. We also used a Diamond Anvil Cell (DAC) apparatus to put extreme pressure on the differently sized bulk samples to study the structural and optical changes that take place. This was done by a combination of insitu Raman and photoluminescence spectroscopy while applying pressure on the samples. We could observe a new emission pathway at pressures higher than 7.8 GPa for the bulk sample which we have attributed to the direct band to band emission. This could appear because of the structural reordering the sample at higher pressures.

Actions (login required)

View Item