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Page 6 of 16 Feng et al. Chem Synth 2023;3:37 https://dx.doi.org/10.20517/cs.2023.26

Figure 3. Schematic illustration of the synthetic procedure for MPDAPs and NMCs via a multi-dimensional molecular self-assembly
strategy. This figure is quoted with permission from Zhang et al. [47] . DAP: 2,6-diaminopyridine; MPDAPs: mesoporous
polydiaminopyridines; NMCs: N-doped mesoporous carbon; PFCA: perfluorinated tetradecanoic acid; PS-b-PEO: polystyrene b
polyethylene oxide.

accurate preparation. Especially in recent years, the breakthrough based on the concept of “single micelle”
assembly mechanisms has great prospects and significance for the precisely controlled preparation of
functional mesoporous materials .
[48]

What is single micelle assembly? First, the formation of mesoscopic structures generally goes through four
processes: liquid crystal mesoscopic phase, micelle monomer formation, micelles assembly and
arrangement, and template agent removal. Although the process has been relatively clear, effective control
of the intermediate phase cannot be achieved. After years of exploration, Zhao et al. found that by using a
two-solvent volatilization system with a large boiling point difference, it is possible to achieve certain
benefits. In this system, it is preferable for the low-boiling solvent to volatilize first, ensuring that the critical
micelle concentration is reached. On the other hand, retaining high boiling point solvents can efficiently
hinder the further assembly and arrangement of micelles, resulting in relatively free discrete micelle
monomers, referred to as single micelles . The single micelle assembly method is to perform subsequent
[49]
secondary assembly through other inducing forces to achieve single micelle level manipulation [50,51] .

Lan et al. provided a new synthesis strategy for mesoporous heterojunction composite structures, the
preparation of ultra-thin single-layer mesoporous structures achieved through precise self-assembly at the
level of a single micelle [Figure 4A]. Through the single micelle assembly method, free single micelle
[52]
monomers are formed in advance as the basic elements to achieve 2D monolayer micelle assembly
[Figure 4B]. Combining the limited 2D directional assembly of titanium-based single micelles with the
interfacial self-assembly of carbon-based single micelles, a 2D heterogeneous interface is obtained, which
ensures the realization of open pores and high contactable specific surface areas, improves the conductivity
of titanium oxide materials, and ensures a stable heterogeneous interface during electrochemical storage.
Therefore, this 2D heterogeneous junction achieves high-performance pseudocapacitive sodium ion storage.

Moreover, the simple and universal single micelle assembly method was employed for precisely controlling
the synthesis of vertically ordered mesoporous carbon films at a centimeter scale on multiple substrates .
[53]
This vertical mesoporous structure can be assembled at the solid-liquid interface, using amphiphilic triblock
copolymers as templates, dopamine (DA) as a carbon source, and trimethylbenzene as fusion and swelling
agents, and mediating the fusion of single molecule micelle into cylindrical micelles. As shown in Figure 5,