2D van der Waals layered oxides such as MoO 3 , V 2 O 5 , and WO 3. Given their vdW nature and thus compatibility with 2D vdW semiconductors, these 2D vdW oxides bear potential as high-κ dielectric materials for a facile integration with 2D vdW semiconductors for future 2D electronics and optoelectronics. [17,18] Specifically, MoO 3 is an attractive material to study due to its multifunctionality for many different applications. MoO 3

for electronic devices. Oxides constitute a broad family of materials with a wide range of potential applications, from catalysis to electronic, photonic, ferroelectric, magnetic and multiferroic functionalities. Understanding structure-property relations in free-standing, supported, and confined two-dimensional ceramics or "ceramic flatlands" has been identified as one of the challenges for future work in ceramics by a recent National Science Foundation workshop. [9] Nonetheless, over the last decade, there have been many reviews on 2D oxides either as the main focus or as a part of a more general nano-materials focused review papers or books. One of the earlier reviews of nanosheets of oxides and hydroxides focused on synthesis, properties -especially photon-induced behavior -and their assembly, was published in 2010 by Ma et al. [11], followed by a second review [12] as a part of a special issue on "2D Nanomaterials beyond Graphene" in 2015. Around the same time (2011) another review by Mas-Balleste et al.[13] also emphasized the importance and variety of 2D oxides. A more recent focused review on 2D oxides can be found in 2019 paper of Hinterding et al.