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materials that can be readily tailored. In recent years, covalent organic frameworks (COFs) and metal-
organic frameworks (MOFs) have received tremendous attention from the materials science community as
they can form tailored microstructures with metal-organic linker coordination bonds or covalent
bonds [32-34] . In addition, the material itself can be chemically active and biocompatible, as some types of
COFs are studied for cancer diagnosis and therapy [35-37] . Thanks to their high surface area, tunable structure,
biocompatibility and diverse topology, these materials have been recognised as a promising functioning host
matrix to mitigate some of the issues that quantum dots had. In view of this prosperous research area, we
have outlined the quantum dots encapsulation in these emerging microporous materials and their potential
applications. We believe that this Perspective will guide the potential future research directions in emerging
QDs embedment in functional porous materials. The purpose of this Perspective is not to provide a
comprehensive review and summary of these composite materials, but instead to give a brief history of the
field, a summary of current progress, and, more importantly, highlight and discuss unsolved questions that
are worth further investigation.

A HISTORICAL OVERVIEW OF QUANTUM DOTS WITHIN MICROPOROUS STRUCTURE
Quantum dots (QDs) are nanocrystals that exhibit quantum confinement effects due to their small size,
leading to unique optical and electronic properties. These properties arise from the confinement of
electrons and holes in a three-dimensional space, resulting in a behaviour similar to an atom because of
quantum physics. It is generally agreed that the first QDs were discovered by Russian physicist Alexei
Ekimov in the early 1980s. He synthesised copper chloride (CuCl ) and cadmium selenide (CdSe)
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nanocrystals embedded in a glass matrix and observed a gradient of colours in the fluorescence emission
[38]
spectra, which was dependent on the size of the nanocrystals . Ever since their discovery, much of the
research on QDs has focused on improving size control to reduce size variation, producing high-quality
nanocrystals, and achieving tunable fluorescence colours. Recently, significant improvements have been
made in the quality and tunability of QDs, as well as in their photovoltaic applications such as in solar cells.
However, QDs have a tendency to aggregate into larger particles due to their high surface energy, which can
lead to the loss of their unique characteristics and efficiency. To mitigate this drawback, there have been
attempts to fabricate QDs within microporous matrices in order to not only control the size of the QDs but
also provide a protective layer that prevents their aggregation and loss of unique characteristics.

Mesoporous silica, zeolites, and porous carbon have conventionally been studied as templates for the
growth of QDs. Among these, zeolites have received extensive attention due to their unique tunable
characteristics and excellent stability. Zeolites are crystalline aluminosilicate polymers with an inorganic
framework consisting of SiO and AlO tetrahedra. They possess a three-dimensional nanometre-sized
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structure with uniform windows, channels, and cavities, and have been extensively studied. While this
family of materials may not be considered as “emerging” compared to other types of microporous materials,
they can still offer valuable insights into regulating the structure, interface, and chemistry between the
microporous template and guest QDs. Therefore, this Perspective will first provide a brief summary of early
studies on using zeolite templates for encapsulating QDs. The unique properties of zeolites that combine
features of both ionic and covalent crystals arise from the covalent network structures formed by sharing
oxygen atoms between SiO and AlO tetrahedra, which depends on the Si/Al ratio [39,40] . Materials exhibiting
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a ratio greater than 3 are categorised as high silica zeolites or zeolite Y. These high silica zeolites have good
physical and chemical stability as well as hydrophobicity . When the ratio is less than 3, it is called zeolite
[41]
X or low-silica zeolites. These zeolites display high ion exchange capacity, which makes them good
candidates as ion exchange agents . Furthermore, pore size can also be tuned by changing the ratio and
[42]
number of oxygen atoms connections to tetrahedra structure, or more directly through different synthetic
conditions such as the use of surfactants. Their three-dimensional porous structure, along with their