Photochromic rare earth oxyhydride materials are groundbreaking in the field of smart materials due to their unique ability to change color in response to light. These materials dynamically adjust their optical properties when exposed to UV or visible light, transitioning between a yellow, transparent state and a black, opaque state. This photochromic behaviour is reversible. The importance of these materials spans various applications. In energy-efficient smart windows, they can control the amount of light and heat entering buildings, contributing to significant energy savings in heating and cooling. Additionally, their use in sunglasses enhances user comfort and vision by automatically adjusting to changing light conditions, reducing eye strain. However, structural knowledge of these materials is limited, which is very important for the further development of these materials. Moreover, the structural changes associated with the colour change is not well known, which limits our understanding of this phenomenon.
Therefore, in this work, we explore the local structure, dynamics of the several components that make up these materials using spectroscopic techniques such as Solid State Nuclear Magnetic Resonance. We carry out these experiments both for the illuminated and the non-illuminated phases of the these materials to unravel the mechanism of the colour change.
I completed my Bachelor’s in the year 2016 pursuing Chemistry honours from Presidency College, Kolkata (India) which is also my hometown. I then went to Madras, to complete my Master’s in Chemistry in Indian Institute of Madras (I.I.T Madras) in the year 2018 and received best thesis award for my work on Computational Chemistry. I then completed my PhD from Radboud University (2018-2023), in group of Prof. Arno Kentgens. During my PhD, I worked on structure-function elucidation of rare earth oxyhydride based photochromic thin film materials and used solid state NMR and DFT as my characterization tools. I am presently a post-doctoral research associate (PDRA) in the University of Birmingham, UK (starting February, 2024), working in the group of Prof. Dominik Kubicki. Currently, I am working on lead halide perovskite based solar cell materials, where we make the materials by ball milling and characterize them with solid state NMR techniques.