Publication date: 17th July 2025
Polycrystalline perovskite thin films are consistently associated with high performance optoelectronic devices. The main challenges currently under the spotlight lie with the stability and reliability of these devices, requiring a better understanding of the thin film surfaces and interfaces. However, very little is known about them. Given the soft nature of these materials, there is a struggle to directly assign the origin of the electronic features and to correlate them to the chemical nature of the surfaces. Here, by exploiting a multimodal approach, we measure for the first time, at sub-micron scales, the diffraction patterns of the thin film grain surface, which provide the material fingerprint, and its related electronic properties. Armed with this knowledge, we are eventually able to unambiguously assign the origin of the photoemission spectra for a wide library of metal halide perovskites. In lead halide perovskites, we identified their photoemission spectra to be the convolution of three different spectra, that of pristine perovskite, lead halide inclusions, and metallic lead. In particular, metallic lead is identified to be the origin of the often-reported mid-gap photoemissive states, generally assigned to deep electronic states within the halide perovskite semiconductor band gap. The chemical composition of the metal halides, the photo-degradation of the perovskites under visible light, and the quality of the precursors heavily define the presence of such states. Overall, the achievement of such understanding elucidates the origin of carrier loss, photo-degradation, and sample reproducibility, aiding in the targeted improvement of the stability and reliability of these metal halide perovskites and their associated optoelectronic devices.
nanoGe is a prestigious brand of successful science conferences that are developed along the year in different areas of the world since 2009. Our worldwide conferences cover cutting-edge materials topics like perovskite solar cells, photovoltaics, optoelectronics, solar fuel conversion, surface science, catalysis and two-dimensional materials, among many others.
Previously nanoGe Spring Meeting (NSM) and nanoGe Fall Meeting (NFM), MATSUS is a multiple symposia conference focused on a broad set of topics of advanced materials preparation, their fundamental properties, and their applications, in fields such as renewable energy, photovoltaics, lighting, semiconductor quantum dots, 2-D materials synthesis, charge carriers dynamics, microscopy and spectroscopy semiconductors fundamentals, etc.
International Conference on Hybrid and Organic Photovoltaics
International Conference on Hybrid and Organic Photovoltaics (HOPV) is celebrated yearly in May. The main topics are the development, function and modeling of materials and devices for hybrid and organic solar cells. The field is now dominated by perovskite solar cells but also other hybrid technologies, as organic solar cells, quantum dot solar cells, and dye-sensitized solar cells and their integration into devices for photoelectrochemical solar fuel production.
Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics
The main topics of the Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP) are discussed every year in Asia-Pacific for gathering the recent advances in the fields of material preparation, modeling and fabrication of perovskite and hybrid and organic materials. Photovoltaic devices are analyzed from fundamental physics and materials properties to a broad set of applications. The conference also covers the developments of perovskite optoelectronics, including light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.
The International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics (NIPHO) is the best place to hear the latest developments in perovskite solar cells as well as on recent advances in the fields of perovskite light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.