Structural Phase- and Degradation-Dependent Thermal Conductivity of CH3NH3PbI3 Perovskite Thin Films

• DOI: 10.1021/acs.jpcc.6b00513
• Publication Date: 2016-03-16T15:29:53Z
• Authors: Zhi Guo; Seog Joon Yoon; Joseph S. Manser; Prashant V. Kamat; Tengfei Luo
• Keywords: Phonon scattering; Tetragonal crystal system

Organic–inorganic lead halide perovskites have shown great promise in photovoltaics and optoelectronics. In these applications, device performance reliability can be strongly influenced by thermal transport the materials. Through laser pump–probe experiments, different microstructures of CH3NH3PbI3 perovskite thin films are found to give rise phonon scattering mechanism. The conductivity neat film decreases with temperature. Even though this agrees behavior its bulk crystalline counterparts, an apparent change near structural phase transition temperature (orthorhombic vs tetragonal) has only been observed spin-coated films. Analyses suggest that may attributed either energy landscape related organic cation disorder or thickness ferroelectric domain walls formed affects at boundaries. contrast, no discontinuity CH3NH3PbI3/Al2O3 mesostructured films, where first shows increasing trend low (<80 K) then stays nearly constant. Such a is typical amorphous materials nanostructured composites scatterings due morphological internal interfaces play key roles transport. When exposed ambient environment, humidity induced degradation significant impact on overall film.