Physics of 2d semiconductors I am trying to find more resource (textbooks, lecture notes) about the physics of 2D semiconductors.
I have experiences with normal semiconductors and  the physics behind the electronic band structure and different theories such as nearly free electron model and the Kronig–Penney model.
However I am having a hard time connecting the physics of normal semiconductors to  a 2d semiconductors.
Can anyone recommend any resource which talks about the physics and model of a 2d semiconductor and most importantly the band gap struture of 2d semicondcutors .
 A: "The Physics of Low-dimensional Semiconductors: An Introduction" by John H. Davies is kind of the (introductory) bible for this. It covers 2D semiconductors in the vein of heterosructures (e.g. quantum wells) as opposed to graphene-like materials (discovered after the book was written). If you have a basic understanding of 3d-semiconductors, you should find the book accessible. Davies style is usually good for developing intuition (rather than just bombarding you with equations).
A: This nature review paper may be a good introduction.
Chaves, A., Azadani, J.G., Alsalman, H. et al. Bandgap engineering of two-dimensional semiconductor materials. npj 2D Mater Appl 4, 29 (2020). https://doi.org/10.1038/s41699-020-00162-4

This review is organized as follows: we first provide a survey of the bandgaps of several 2D materials, along with a brief discussion about their most interesting features. We then discuss the influence of the number of layers on the bandgap and the excitonic properties in van der Waals heterostructures (vdWH). Next, we review the latest developments on the use of external electric fields, dielectric environment, and strain engineering for the control of the energies of QP gaps and excitonic peaks in 2D materials. Further, we review the effects of molecular intercala- tion, chemical doping, and alloying on the bandgap. Finally, the bandgap closing and metal–insulator transition in transition-metal dichalcogenides (TMDCs) mediated by structural phase transitions is discussed, followed by our concluding remarks.

A: A great complimentary resource to connect knowledge on semiconductors with the physics of 2D semiconductors is the following document: Ph.D. Thesis - Optical spectroscopy and hyloscopy of monolayers of tungsten disulphide
The main chapter to read is the Chapter 2: "Monolayers of TMDs" and supplementary for more details. All knowledge from this chapter is transferable to all 2D materials.
