[10a-Z23-1~8] 4.7 Quantum Optics and Nonlinear Optics

▲ [10a-Z23-3] Visualizing Carrier Trapping at the Nanoscale in Hybrid Organic-Inorganic Perovskite Films

〇(DC)Andrew Justin Winchester¹、Stuart Macpherson²、Tiarnan Doherty²、Christopher E. Petoukhoff¹、Mojtaba Abdi-Jalebi²、Zahra Andaji-Gamaroudi²、Sofiia Kosar¹、Vivek Pareek¹、E Laine Wong¹、Julien Madeo¹、Michael K. L. Man¹、Samuel D. Stranks²、Keshav M. Dani¹ (1.Okinawa Inst. of Sci. & Tech.、2.Univ. of Cambridge)

キーワード：impurity, defect, deep level, perovskite solar cells, ultrafast phenomenon

Hybrid organic-inorganic perovskite (HOIP) materials have received notable attention for their development and use in photovoltaic devices. In spite of their rapid development, the nature of defects which act as recombination centers is still under investigation. In particular, reports have suggested that traps in HOIP could be localized on a sub-micrometer size within the material, however this has not been well understood due to the limited spatial resolution of optical techniques. In this work, we directly show the nanoscale extent of traps in an HOIP film using time-resolved photoemission electron microscopy (TR-PEEM). We find that traps are localized in nanoscale clusters on the order of 10s of nanometers in size. We show that these clusters are hole traps, and observe the hole trapping kinetics using time-resolved measurements. Our work provides a new avenue for understanding the fundamental properties of traps in HOIP materials.