The molecular mechanism of apatite formation on bioactive glass surface is studied using the techniques of XRD, EDX, SEM, FT-IR, and solid-state 31 P NMR. Using the sol-gel method a bioactive glass system containing glass beads of 2 to 3 microns in size is prepared with the composition containing 30% CaO -70% SiO 2 . Our experimental data support the apatite formation mechanism proposed by Hench concerning the precipitation and crystallization of calcium phosphate. The phosphate ions initially deposited on the glass surface are largely in amorphous phase and have substantial amount of water molecules in the surrounding. As the soaking time in simulated body fluid increases, some of the water molecules diffuse out of the phosphate lattice, leading to the formation of a crystalline phase. Our data show that the structure of the crystalline phase is different from type B carbonate apatite but similar to hydroxyapatite.

Facile synthesis of mesoporous silica SBA-15 with additional intra-particle porosities has been demonstrated by using the carboxylate-terminated triblock copolymer Pluronic P123 as the structural directing agent. The thus prepared materials are promising for applications in which efficient diffusion of molecules is in great demand.

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Enzymatic catalysis has fueled considerable interest from chemists due to its high efficiency and selectivity. However, the structural complexity and vulnerability hamper the application potentials of enzymes. Driven by the practical demand for chemical conversion, there is a long-sought quest for bioinspired catalysts reproducing and even surpassing the functions of natural enzymes. As nanoporous materials with high surface areas and crystallinity, metal−organic frameworks (MOFs) represent an exquisite case of how natural enzymes and their active sites are integrated into porous solids, affording bioinspired heterogeneous catalysts with superior stability and customizable structures. In this review, we comprehensively summarize the advances of bioinspired MOFs for catalysis, discuss the design principle of various MOF-based catalysts, such as MOF−enzyme composites and MOFs embedded with active sites, and explore the utility of these catalysts in different reactions. The advantages of MOFs as enzyme mimetics are also highlighted, including confinement, templating effects, and functionality, in comparison with homogeneous supramolecular catalysts. A perspective is provided to discuss potential solutions addressing current challenges in MOF catalysis.

As water scarcity becomes a pending global issue, hygroscopic materials prove a significant solution. Thus, there is a good cause following the structure–performance relationship to review the recent development of hygroscopic materials and provide inspirational insight into creative materials. Herein, traditional hygroscopic materials, crystalline frameworks, polymers, and composite materials are reviewed. The similarity in working conditions of water harvesting and carbon capture makes simultaneously addressing water shortages and reduction of greenhouse effects possible. Concurrent water harvesting and carbon capture is likely to become a future challenge. Therefore, an emphasis is laid on metal–organic frameworks (MOFs) for their excellent performance in water and CO2 adsorption, and representative role of micro‐ and mesoporous materials. Herein, the water adsorption mechanisms of MOFs are summarized, followed by a review of MOF's water stability, with a highlight on the emerging machine learning (ML) technique to predict MOF water stability and water uptake. Recent advances in the mechanistic elaboration of moisture's effects on CO2 adsorption are reviewed. This review summarizes recent advances in water–harvesting porous materials with special attention on MOFs and expects to direct researchers’ attention into the topic of concurrent water harvesting and carbon capture as a future challenge.

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