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adsorption.

The future of MOFs holds immense potential for innovation and impact across various industries. To
advance the field of next-generation flame-retardant materials, we present a concise vision for
industrialization, versatility, ligand synthesis, and MOF derivatives. This perspective is both timely and
forward-looking, offering new insights and inspiration for senior researchers, deepening the understanding
of young researchers, and providing guidance for those in related fields interested in the development of
flame-retardant materials. Our work aims to provide valuable insights for a wide range of researchers and
facilitate future advancements in this crucial field. We are confident that our article will make a significant
contribution to the ongoing efforts toward developing safer and more sustainable materials for diverse
applications.

INDUSTRIAL APPLICATION OF MOF-BASED FLAME RETARDANTS
Larger scale synthesis of MOF-based flame retardants
MOFs are typically synthesized in small quantities in a laboratory setting due to the intricate nature of their
synthesis. For instance, the UIO and MIL series of MOFs necessitate a hydrothermal synthesis process
followed by a high-temperature reaction in a reaction vessel [30,31] . Achieving the desired MOF structure and
properties requires meticulous control of reaction conditions, including temperature, pressure, and solvent
composition. This process requires a significant amount of time. Even zeolite imidazolate skeleton materials
(ZIFs), synthesized by facile methods, necessitate prolonged aging for the attainment of a flawless crystal
structure [32,33] . The aging process is essential for the formation of intermolecular hydrogen bonds between
metal ions and ligands, which stabilize the MOF structure and prevent collapse. The duration of aging can
vary from several hours to several days, depending on the specific MOF being synthesized and the desired
crystal quality.

To achieve commercial viability, MOFs must be produced on a large scale [Table 2]. Despite the challenges
associated with their synthesis, recent advances in synthetic methods have facilitated industrial production
of MOFs, enabling scaling up to gram or even kilogram quantities [Figure 2]. Continuous-flow reactors are
a commonly employed strategy for the large-scale synthesis of MOFs [34-36] . In this approach, the reactants are
continuously fed into the reactor and undergo controlled mixing and reaction, resulting in a steady-state
production of MOFs. This method offers several benefits, including precise regulation of reaction
parameters, rapid mixing, heat transfer, and continuous product output. A further approach is to employ
the techniques of spray-drying or freeze-drying [37-39] . The spray-drying technique involves the atomization of
a liquid MOF precursor into small droplets, which are subsequently dried using a stream of hot air. As these
droplets traverse through the drying chamber, the solvent evaporates, leaving behind solid MOF particles.
The method is highly efficient in the production of MOF powders and can be readily scaled up for large-
scale manufacturing.

Freeze-drying involves freezing a liquid MOF precursor and subsequently eliminating the solvent under
vacuum conditions. The frozen specimen is then placed in a vacuum chamber where the solvent sublimates
directly from the solid to the gas phase, resulting in a desiccated MOF powder. Freeze-drying is a more
time-consuming process compared to spray-drying; however, it has the ability to maintain the crystalline
structure of MOFs intact, which can prove crucial for certain applications. Both methods are capable of
producing MOFs with high surface area, porosity, and thermal stability, rendering them highly versatile for
a wide range of applications. Additionally, they facilitate the production of MOFs in powder form, which is
more manageable and storable. Apart from that, the cost of MOFs can significantly affect large-scale
production. Generally, the higher the cost of ligands, the greater the expense of producing MOFs. The price