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Page 2 of 16 Feng et al. Chem Synth 2023;3:37 https://dx.doi.org/10.20517/cs.2023.26

INTRODUCTION
Functional mesoporous materials have attracted widespread attention due to their merits of high surface
area, large pore volume, tunable nanostructures, and diverse compositions. They have broad application
potential in catalysis , energy storage , gas adsorption separation , sensing , and other fields [8-10] . The
[2-5]
[1,2]
[7]
[6]
mesoporous materials obtained by traditional strategies are generally bulk materials, which are three-
dimensional ordered assemblies with nanopores. Their internal active sites cannot be fully exposed and are
not conducive to the rapid transport of guest molecules in the pores, which greatly limits their application
performance [11,12] . Currently, mesoporous materials can be extended to multilevel architectures from 0
dimensions to 3 dimensions through bottom-up self-assembly . Despite the fact that considerable progress
[13]
has been made in synthesis methods, it remains a challenge to accurately and directionally design and
synthesize mesoporous materials based on the relationship between structure and properties to meet the
needs of increasingly diverse applications.

Two-dimensional (2D) nanomaterials are a new kind of anisotropic sheet material with lateral dimensions
ranging from several hundred nanometers to several micrometers . Since the first exfoliation and
[14]
[15]
characterization of single-layer graphene in 2004 , 2D materials have gained extensive interest due to their
remarkable mechanical, thermal, electrical, magnetic, and optical properties [16,17] . There have been qualitative
[19]
new members of this family, such as transitional metal dichalcogenides , layered double hydroxides , and
[18]
transition metal carbides and nitrides (MXenes) , and their applications range from fundamental studies
[20]
to electronic and photonic devices. However, 2D materials tend to form dense stacked structures, which
greatly hinder their mass transfer processes and the full utilization of active surfaces.

Two-dimensional mesoporous materials (2DMMs) not only possess the structural advantages of
mesoporous materials but also have ultra-thin 2D geometric structures, which can fully overcome the
shortcomings of traditional bulk mesoporous materials [21,22] . On the one hand, ultrathin 2D morphology
with large lateral dimensions and atomic thickness comes into being a high theoretical specific surface area,
which facilitates the electric structure regulation. On the other hand, pushing mesoporous materials toward
the lateral dimension to form unique 2D nanosheets can effectively solve the drawbacks of bulk materials
and greatly improve mass transfer efficiencies . Therefore, it is of great significance to develop 2DMMs.
[23]
Previous studies have confirmed that self-assembly is an effective strategy for synthesizing 2DMMs [24,25] .
Compared to other synthetic approaches for 2DMMs, such as hard templating methods, a self-assembly
method shows incomparable merits in the flexible control of pore sizes, architecture, and wall thickness,
which determines the final performance of 2DMMs. Over the past few years, through self-assembly
methods, great progress has been made in the development of 2DMMs with a variety of compositions,
morphologies, mesoporous structures, and pore sizes. Herein, we briefly review recent progress in the
fabrication of 2DMMs, focusing on their synthesis strategies, properties, and underlying mechanisms. In
addition, we anticipate potential challenges that 2DMMs may face in future research and identify the
potential development directions and opportunities. We hope that through this review, readers can gain
inspiration and a better understanding of customizing the synthesis of 2DMMs.

INSIGHTS INTO THE SYNTHESIS OF 2DMMS
2DMMs, including inherently layered or non-layered nanosheets, exhibit attractive properties and superior
performance in a variety of application fields and can usually be generated through a “top-down” or
[26]
“bottom-up” strategy . The top-down approach is one of the most commonly used methods to synthesize
2DMMs. In this case, a 2D structure is first prefabricated and then etched or structurally converted into
pores. This method typically produces atomically thin nanosheets with disordered porous and defective