Snapshot Angle-Resolved Spectroscopy and Its Application for Study of Highly Efficient Polariton OLEDs

The multifunctional snapshot angle-resolved spectroscopy (ARS) system capable of electroluminescence, photoluminescence, and reflectance measurements for thin film devices is developed based on the k-space imaging technique. Compared with the conventional goniometric ARS system, this snapshot spectroscopy system offers great advantages of rapid and simple measurement, suitable for characterizing thin film devices that are unstable or degraded under long-time or high-power driving conditions, such as OLEDs. We perform a detailed calibration of the snapshot system and show that the measured results closely match with those obtained using a goniometric system. Furthermore, we show the capabilities of the system with application in studying polariton OLEDs. The result provides comprehensive information on the polariton mode dispersion and emission distribution, and shows an effective radiative pumping of the lower polariton branch for high emission efficiency.

Mesoporous perovskite solar cells with Al- and Zn-based metal-organic frameworks

The improvement of lead halide perovskites solar cells (PSC) by hydrophobic metal-organic frameworks (MOF) is one of the promising tools for modern photovoltaic technology to achieve stable and efficient thin-film devices. To show the MOF applicability for PSC, we incorporate two types of MOF: NH2-MIL-53(Al) and basolite Z1200 in n-i-p mesoporous MAPbI3 based solar cells that can add 2.2% efficiency by increasing main photovoltaic parameters. The simplicity of the proposed MOF’s integration allows to use and adopt this approach to incorporate other frameworks for thin-film perovskite devices.