Halide perovskites have emerged as a new class of semiconductors that have rapidly transformed the field of photovoltaics, reaching power conversion efficiencies that rival—and in some cases exceed—those of established silicon technologies. Beyond their technological relevance, these materials are also of fundamental interest due to their tunable electronic structure and remarkable defect tolerance.

In this talk, I will introduce halide perovskites as promising materials for optoelectronic applications and discuss their role in modern solar cell research and beyond. I will then show how spectroscopy can be used to gain insight into their electronic structure and other device-relevant material properties. In particular, I will present our work using ultraviolet photoelectron spectroscopy and reflection electron energy loss spectroscopy to study lead- and tin-based perovskites, supported by density functional theory.

Overall, I aim to highlight halide perovskites not only as highly efficient photovoltaic materials, but also as a versatile platform for addressing fundamental questions in condensed matter physics.