The use of precrystallized nanoparticles as nanobuilding blocks (NBBs) is a promising way to obtain mesoporous materials with crystalline walls. In this study, the size effects of both hydroxide NBBs and nonionic block copolymer (BCP) templates on the formation of ordered mesostructures are investigated. The diameter of layered nickel hydroxide NBBs was controlled at the sub-2 nm scale by an epoxidemediated alkalinization process. Commercially available nonionic BCPs (gyration radii in the range of 11.9−43.9 Å) were used. Mesoperiodic structures were formed by the evaporation-induced self-assembly process. A proper size combination of hydroxide NBBs, smaller than 12.5 Å, and BCPs, larger than 19.9 Å, is shown to be necessary to form ordered mesostructures.

The present work is partially supported by JSPS KAKENHI Grant Number JP20K15368 and Core-to-Core Program, 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).