Organic−Inorganic Hybrid Nanocrystal-based Cryogels with Size- Controlled Mesopores and Macropores

Nanocrystal-based processing has attracted significant interest for the fabrication of highly functional materials with controlled crystallinity and fine porous structures. In this study, we focused on the template-free synthesis of nanocrystal-based materials with size-tailored pores using layered nickel hydroxide intercalated with acrylate anions. Polymerization of the acrylates encouraged interconnection of the nanocrystals and the formation of homogeneous gel networks. Cryogels after freeze-drying had pores with an average diameter from 4.8 nm (mesoscale) to 68.9 nm (macroscale). It was found that the surface characteristics of starting nanocrystals determined the phase separation tendency of interconnected species from the reaction media and resultant porous structures. We believe that the present study can enable the design of template-free nanocrystal-based porous materials.The present work was partially supported by JSPS KAKENHI (JP20K15368), the MEXT Leading Initiative for Excellent Young Researchers, the Foundation for the Promotion of Ion Engineering, and the Izumi Science and Technology Foundation (2019-J-112)