The innovation of advanced technology and the requirement of electronic market are always focusing on low cost electronics, presenting an easy processing and having enhanced performance. Organic-inorganic hybrid perovskites, which combine the properties of organic and inorganic semiconductors, are hopeful candidates for future opto-electronic devices. The exciton binding energies and oscillator strengths are very large in these systems making the applications at room temperature possible. In this thesis, we study the flexibility and photostability of self-assembled two-dimensional layered perovskites (R-NH3)2PbX4. By modifying the R structure, perovskites with optimized photoluminescence efficiency, surface roughness and photostability are discovered. We develop also some methodologies to fabricate crystal bulks and nanoparticles of perovskites, and we create new mixed perovskite crystals: (RNH3)2PbYxX4-x and AB-(NH3)2PbX4. Vertical microcavities containing these new materials and working in the strong coupling regime at room temperature have been realized, the emission of the lower energy polariton is observed.
