Natural sugars as templating agents show unique advantages in the synthesis of hierarchical ZSM-5 zeolite, which provide a promising alternative to the traditional templating method due to their green, cost-effective, pore-size-adjustable, and mild template-removal conditions. In addition, the differences between the molecular structures of different sugar templates exhibit unique regulatory properties in the synthesis of hierarchical ZSM-5 zeolite. Specifically, glucose and sucrose induce linear stacking of nanocrystals through hydroxyl coordination, and form a uniform intergranular mesoporous structure by combining with hydrothermal or two-step crystallization, which can effectively enhance the dispersion of loaded metals. But their ability to regulate the pore channels is weak. Other templating agents are needed to synergistically regulate pore structure. For example, polysaccharide templates, such as cellulose and starch, have branched chain structure. By using hydrothermal method or seed crystallization method, they can construct micro-medium-macroporous multilevel pore structure, and realize synergistic distribution of inter-crystalline mesopores and intra-crystalline mesopores. Polysaccharides and sodium alginate, serving as functional sugars, promote the formation of uniform and dendritic mesopores through electrostatic adsorption and carboxyl (—COO—)Al³⁺ chelation, respectively. They also enhance the density of acidic sites (Lewis) on the surface and regulate the morphology of molecular sieves. These modifications tailor the material for high-value-added applications, such as esterification of oleic acid with high acidity, the diffusion-controlled adsorption of macromolecules, and biomass conversion. By improving mass transfer efficiency and accessibility of acidic sites, the sugar templates can significantly enhance the performance of biomass conversion, promote the transformation of biomass from "waste" to "carbon neutral core carrier", and provide a sustainable solution to the goal of "dual carbon".

Although the natural sugar templates in hierarchical ZSM-5 zeolite to make significant progress, the field of research is still facing numerous challenges. Firstly, some of the sugar templates still suffer from complex pretreatment, wide mesopore size distribution, and high mesopore volume, leading to the decrease of crystallinity for synthesis of hierarchical ZSM-5 zeolite. Secondly, the existing synthesis techniques are mainly limited to hydrothermal methods, and other methods such as dry gel conversion and two-step crystallization are hindered in industrialization due to the complexity of the process and cost factors; finally, it is difficult to precisely regulate the pore structure and acidic sites of the molecular sieves, and the constitutive relationship between the templating agent dosage and the material properties has not been fully clarified. Therefore, exploring the controlled depolymerization of polysaccharides and multi-template compounding strategy to break through the bottleneck of crystallinity and mesopore homogeneity, developing more universal synthesis methods, exploring the mechanism of pore-acid synergistic regulation, and in-depth analysis of the mechanism of templating agents are the main directions of the future research, so that we can push forward the practical application of sugar templating method in the large-scale preparation of hierarchical zeolite.