Photoluminescence properties of ultrathin CsPbCl3 nanowires on mica substrate

Fabricating high-quality cesium lead chloride (CsPbCl3) perovskite nanowires (NWs) with dimension below 10 nm is not only of interests in fundamental physics, but also holds the great promise for optoelectronic applications. Herein, ultrathin CsPbCl3 NWs with height of similar to 7 nm, have been achieved via vapor phase deposition method. Power and temperature-dependent photoluminescence (PL) spectroscopy is performed to explore the emission properties of the CsPbCl3 NWs. Strong free exciton recombination is observed at similar to 3.02 eV as the temperature (T) is 78-294 K with binding energy of similar to 37.5 meV. With the decreasing of T, the PL peaks exhibit a first blueshift by 2 meV for T similar to 294-190 K and then a redshift by 4 meV for T similar to 190-78 K. The exciton-optical phonon interaction plays a major role in the linewidth broadening of the PL spectra with average optical phonon energy of similar to 48.0 meV and the interaction coefficient of 203.9 meV. These findings advance the fabrication of low dimensional CsPbCl3 perovskite and provide insights into the photophysics of the CsPbCl3 perovskite.