Understanding lattice dynamics and thermal transport mechanisms in cubic hybrid organic–inorganic perovskites remain challenging due to strong anharmonicity and phase transitions.Here,we investigate the thermal trans...Understanding lattice dynamics and thermal transport mechanisms in cubic hybrid organic–inorganic perovskites remain challenging due to strong anharmonicity and phase transitions.Here,we investigate the thermal transport behavior in benchmark cubic hybrid perovskite FAPbI_(3)by coupling first principles-based anharmonic lattice dynamics with a linearized Wigner transport equation.Using the Temperature-Dependent Effective Potential(TDEP)method,we stabilize the negative soft modes,primarily dominated by organic FA+cations.Our calculations predict an ultra-low thermal conductivity of~0:63Wm^(-1)K^(-1)at 300 K,following a temperature dependence of T^(−0.740).Contrary to common assumptions,we find that the[PbI_(3)]^(1-)units,rather than FA^(+)cations,dominate thermal resistance.Furthermore,we demonstrate that anharmonic force constants are highly temperature-sensitive,relying on 0-K force constants significantly underestimates thermal conductivity.Our study not only elucidates the microscopic mechanisms governing thermal transport in FAPbI_(3)but also provides a robust framework for modeling heat conduction in hybrid organic-inorganic compounds.展开更多
基金funding by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division, under Contract No. DE-AC02-05-CH11231: Materials Project program KC23MPR.G. acknowledges support from the Excellent Young Scientists Fund (Overseas) of Shandong Province (2022HWYQ091) and the Initiative Research Fund of Shandong Institute of Advanced Technology (2020107R03)+5 种基金B.H. acknowledges the financial support from the Science and Technology Planning Project of Guangdong Province, China (Grant No. 2017A050506053)the Science and Technology Program of Guangzhou (No. 201704030107)the Hong Kong General Research Fund (Grants No. 16214217 and No. 16206020)This paper was also supported in part by the Project of Hetao Shenzhen-Hong Kong Science and Technology Innovation Cooperation Zone (HZQB-KCZYB2020083)C.L. acknowledges the support from the Sinergia project of the Swiss National Science Foundation (grant number CRSII5_189924)Z.C. acknowledges support from the Fundamental Research Fund for Zhejiang Ocean University (Grant No. JX6311181423).
文摘Understanding lattice dynamics and thermal transport mechanisms in cubic hybrid organic–inorganic perovskites remain challenging due to strong anharmonicity and phase transitions.Here,we investigate the thermal transport behavior in benchmark cubic hybrid perovskite FAPbI_(3)by coupling first principles-based anharmonic lattice dynamics with a linearized Wigner transport equation.Using the Temperature-Dependent Effective Potential(TDEP)method,we stabilize the negative soft modes,primarily dominated by organic FA+cations.Our calculations predict an ultra-low thermal conductivity of~0:63Wm^(-1)K^(-1)at 300 K,following a temperature dependence of T^(−0.740).Contrary to common assumptions,we find that the[PbI_(3)]^(1-)units,rather than FA^(+)cations,dominate thermal resistance.Furthermore,we demonstrate that anharmonic force constants are highly temperature-sensitive,relying on 0-K force constants significantly underestimates thermal conductivity.Our study not only elucidates the microscopic mechanisms governing thermal transport in FAPbI_(3)but also provides a robust framework for modeling heat conduction in hybrid organic-inorganic compounds.
