In addition, a lot of developments have been made in the exploration of the effects of the size, shape, microstructure, and surface conditions (e.g. surface defects and capping ligands) of BaTiO3 NCs on their dielectric and ferroelectric properties with the utilization of many advancedcharacterization methods such as piezoresponse force microscopy (PFM),61–63 neutron scattering,64–67 and electron microscopy.68–71 To further elucidate the underlying mechanism of the dielectricand ferroelectric behavior of BaTiO3 at the nanoscale, several models have been proposed.72–74 Moreover, the practical application of BaTiO3/polymer nanocomposites requires that the BaTiO3NCs can be homogeneously dispersed within the polymer matrix without phase separation or particle agglomeration. This has triggered recent significant research efforts into the development of surface modification techniques that enable high-quality BaTiO3/polymer nanocomposites with uniform dispersion and favorable morphology as compared to traditional simple mixing approaches.