Investigation on thermal transport and structural properties of InFeO₃(ZnO)_m with modulated layer structures

We investigate the thermal transport and structural properties of InFeO₃(ZnO)_m (m = 1, 2, 3, 4, 5) with modulated layer structure, through high resolution transmission electron microscopy and theoretical calculation. Interestingly, we find that the thermal conductivities dependent on the m numbers and stacked layers. Elastic properties indicate that InFeO₃(ZnO)_m with m odd numbers possesses weaker chemical bonding and lower thermal conductivity than those of InFeO₃(ZnO)_m with m even numbers. The calculated thermal conductivities show well consistent with the experimental data through integrating the contributions from Umklapp phonon-phonon scattering, stacking faults and optical branch. The results show that thermal conductivities of InFeO₃(ZnO)_m are predominantly determined by stacking faults, especially in the low temperature range. Our finding provides new insight into seeking the materials with low thermal conductivity through artificially designing layer structures.