Exfoliating layered double hydroxides in formamide: a method to obtain positively charged nanosheets

Abstract
Exfoliation of layered double hydroxides (LDHs) into single layers provides a new type of nanosheet with ultimate two-dimensional anisotropy and positive charge. In this Highlight article, we briefly review the latest advances in this emerging field. In comparison with the previous studies, we show that micrometer-sized and well-defined LDH nanosheets can be readily attained by synthesizing large crystals of LDH-carbonate via so-called homogeneous precipitation and subsequent exfoliation of the nitrate form in formamide. Some general aspects including the exfoliating process and characterization, a plausible delaminating mechanism, and future challenges, are presented and discussed.