Stabilization of CsPbBr3 quantum dots for photocatalysis, imaging and optical sensing in water and biological medium: a review

Abstract

Of all the quantum dots, CsPbBr₃ perovskite quantum dots (CPQDs) have been extensively studied for sensing and photocatalysis because of their desired photophysical properties such as optical absorption, high quantum yield and narrow emission bands. However their photo, thermal and aqueous instability has limited their use in real time applications. The review provides a fundamental understanding of this material's intrinsic behavior towards these degradation factors and discusses elaborately about the various strategies being implemented namely surface passivation through (a) ligand exchange/doping, (b) coating silica shells and (c) developing polymer encapsulations to tweak its behaviour for water related applications. A detailed track record against our focussed set of qualities for developing water stable CPQDs will help us look ahead in the right direction. It provides an assessment of the figures of merit of these tweaked or stabilized CPQDs, to check the reliability of this material for photocatalysis and biosensing in water. The insights offered here however open scope, not only for developing various other water stable, lead free and double perovskites which are environmentally more benign and useful, but would also give perspectives to validate their developed schemes towards the use of these materials for water related applications.