Organic-inorganic hybrid halide perovskites have emerged as a new semiconductor platform for next-generation optoelectronic devices. The standard “3D” perovskite materials, with chemical formula ABX3, where A represents an organic cation, B represents a metal, and X represents a halide, have shown immense promises due to its high power conversion efficiencies (compared to silicon). However, their intrinsic instability under realistic operating conditions limits their implementation in optoelectronic technologies of the future. On the other hand, layered two-dimensional (2D) perovskites, a subclass of hybrid perovskites, have demonstrated stability performances closer to industrial standard but with a lower efficiencies. These materials are composed of large organic molecules which are inserted into their lattice, breaking the 3D perovskite structure into layered slabs of controllable thickness and composition. In this thesis, we will explore the advances in fabricating 2D and 3D halide perovskite materials for high performance optoelectronic applications and understand the structural dynamics of halide perovskites during thin-film formation and external stimuli (realistic operating conditions). This dissertation is split into 4 main parts. First, I will be discussing the background of halide perovskite (both 2D and 3D) through a structure standpoint. Second, I will be reporting a unique approach to synthesize phase pure high n value 2D perovskite single crystals that utilizes machine learning. In addition, I will discuss a novel fabrication process of synthesizing phase pure 2D perovskite thin-films for solar cell application. Third, we will continue the work by discussing the durability of the 2D perovskite devices and the structural and electronic behaviors under light illumination. Lastly, we will tackle the problem of fabricating phase stable "black” alpha-phase FAPbI3 perovskite using 2D perovskite crystals as additives.