β-glucan is a type of polysaccharide which widely exists in bacteria, fungi, algae, and plants, and has been well known for its biological activities such as enhancing immunity, antitumor, antibacterial, antiviral, and wound healing activities. The conformation of β-glucan plays a crucial role on its biological activities. Therefore, β-glucans obtained from different sources, while sharing the same basic structures, often show different bioactivities. The basic structure and inter-molecular forces of polysaccharides can be changed by modification, which leads to the conformational transformation in solution that can directly affect bioactivity. In this review, we will first determine different ways to modify β-glucan molecules including physical methods, chemical methods, and biological methods, and then reveal the relationship of the flexible helix form of the molecule chain and the helix conformation to their bioactivities. Last, we summarize the scientific challenges to modifying β-glucan’s conformation and functional activity, and discuss its potential future development.

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Hierarchical porous carbons (HPCs) hold great promise in energy-related applications owing to their excellent chemical stability and well-developed porous structures. Attention has been drawn toward developing new synthetic strategies and precursor materials that permit greater control over composition, size, morphology, and pore structure. There is a growing trend of employing metal–organic frameworks (MOFs) as HPC precursors as their highly customizable characteristics favor new HPC syntheses. In this article, we report a biomimetically grown bacterial-templated MOF synthesis where the bacteria not only facilitate the formation of MOF nanocrystals but also provide morphology and porosity control. The resultant HPCs show improved electrochemical capacity behavior compared to pristine MOF-derived HPCs. Considering the broad availability of bacteria and ease of their production, in addition to significantly improved MOF growth efficiency on bacterial templates, we believe that the bacterial-templated MOF is a promising strategy to produce a new generation of HPCs.

Three-dimensional (3D) nanoporous architectures, possessing high surface area, massive pores, and excellent structural stability, are highly desirable for many applications including catalysts and electrode materials in lithium ion batteries. However, the preparation of such materials remains a major challenge. Here, we introduce a novel method, instant gelation, for the synthesis of such materials. The as-prepared porous 3D MoS2@C nanocomposites, with layered MoS2 clusters or strips ingrained in porous and conductive 3D carbon matrix, indeed showed excellent electrochemical performance when applied as anode materials for lithium ion batteries. Its interconnected carbon network ensures good conductivity and fast electron transport; the micro-, and mesoporous nature effectively shortens the lithium ion diffusion path and provides room necessary for volume expansion. The large specific surface area is beneficial for a better contact between electrode materials and electrolyte.

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