My research interest includes studies of the thermal transport and mechanical properties of materials based on various levels of atomistic simulations, such as ab initio (DFT) or classical potentials. For my past work, please refer to the publication list for more details.
Effect of the spin transition on the thermal transport in FexMg1-xO
Defects in the lattice structure affect the thermal conductivity of the host material in many different ways. Most commonly studied effects are that of the mass and bond strength differences between impurity atom and a host atom, but other mechanisms also exist. In particular, transition metal impurity might have a multitude of the low-energy electronic levels which can couple to phonons and also affect thermal conductivity, sometimes quite dramatically. Further, if a material is under external stimuli, such as temperature and/or pressure, interatomic electron levels become a function of external influence and that can further modify thermal transport properties. Such situation arises in the Earth interior, where common mineral, ferropericlase (FexMg1-xO), experiences so-called spin transition: Iron ions losing their magnetic moment as the pressure increases. This change affects many properties of the ferropericlase: equilibrium volume, elastic properties, and thermal conductivity. In this project, we are elucidating the effect of this transition on the lattice portion of the thermal conductivity using Boltzmann Transport Equation on the basis of ab initio calculations.
MXenes as a cesium sensors
In this project, we examine the capability of the recently discovered 2D MXenes phases as cesium sensors. These compounds potentially offer tunability of their properties, since nearly 100 different compounds are predicted to exist. At the same time, MXenes had been shown to exhibit excellent selectivity for particular ions, as well as considered for the electrodes in lithium ion batteries. A combination of these properties might make them excellent Cs sensors. In the picture: simulated structure of the Ti3C2 MAX phase with intercalated Cs ions, result of the density function theory calculations.
Designing complex chalcogenides through building block approach
A directed synthesis of materials possessing desired property is the Holy Grail of solid state and materials chemistry. Thhis project addresses this issue through a hypothesis that quaternary or complex structure can be synthesized through a more rational approach if structural building blocks in a ternary alkali metal containing chalcogenides are retained during post-synthetic transformation through a metathesis reaction with metal halides. This approach has huge implications in the synthesis of materials with desired applications since a myriad of building blocks are available within the main group elements (Al, Ga, In, Si, Ge, Sn, P, Sb) with varying negative charge and degree of covalence. Therefore, when executed this project can potentially generate materials that will find applications in cutting edge technologies as in solar photovoltaics, thermoelectrics, solid-state lighting, superionic conductor, and as magnetic materials. My efforts in this project are focused on the modelling of the lowest energies structures that preserve building blocks and predicting their properties through ab initio calculations. This project is supported by NSF.