91 citations · 235 across the 12 of their papers we have counts for
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Inhomogeneous Defect Distribution in Mixed-Polytype Metal Halide Perovskites
Young Won Woo, Zhenzhu Li, Young-Kwang Jung +2
The competition between corner, edge and face-sharing octahedral networks is a cause of phase inhomogeneity in metal halide perovskite thin-films. Here we probe the charged iodine…
Quick-start guide for first-principles modelling of point defects in crystalline materials
Sunghyun Kim, Samantha N. Hood, Ji-Sang Park +2
Defects influence the properties and functionality of all crystalline materials. For instance, point defects participate in electronic (e.g. carrier generation and recombination) a…
Modelling Grain Boundaries in Polycrystalline Halide Perovskite Solar Cells
Ji-Sang Park, Aron Walsh
Solar cells are semiconductor devices that generate electricity through charge generation upon illumination. For optimal device efficiency, the photo-generated carriers must reach…
Stabilization and self-passivation of symmetrical grain boundaries by mirror symmetry breaking
Ji-Sang Park
While computational methods for the study of point defects in materials have received significant attention, methods for the investigation of grain boundaries require further devel…
Open-Circuit Voltage Deficit in Cu2ZnSnS4 Solar Cells by Interface Band Gap Narrowing
Ji-Sang Park, Sunghyun Kim, Samantha N. Hood +1
There is evidence that interface recombination in Cu2ZnSnS4 solar cells contributes to the open-circuit voltage deficit. Our hybrid density functional theory calculations suggest t…
Lone-pair effect on carrier capture in CuZnSnS solar cells
Sunghyun Kim, Ji-Sang Park, Samantha N. Hood +1
The performance of kesterite thin-film solar cells is limited by a low open-circuit voltage due to defect-mediated electron-hole recombination. We calculate the non-radiative carri…
Stability and electronic properties of planar defects in quaternary I2-II-IV-VI4 semiconductors
Ji-Sang Park, Sunghyun Kim, Aron Walsh
Extended defects such as stacking faults and anti-site domain boundaries can perturb the band edges in CuZnSnS and CuZnSnSe, acting as a weak electron barrier or a…
Quick-start guide for first-principles modelling of semiconductor interfaces
Ji-Sang Park, Young-Kwang Jung, Keith T. Butler +1
Interfaces between dissimilar materials control the transport of energy in a range of technologies including solar cells (electron transport), batteries (ion transport), and thermo…
Role of electron-phonon coupling and thermal expansion on band gaps, carrier mobility, and interfacial offsets in kesterite thin-film solar cells
Bartomeu Monserrat, Ji-Sang Park, Sunghyun Kim +1
The efficiencies of solar cells based on kesterite CuZnSnS (CZTS) and CuZnSnSe (CZTSe) are limited by a low open-circuit voltage due to high rates of non-radiative…
Opposing effects of stacking faults and antisite domain boundaries on the conduction band edge in kesterite quaternary semiconductors
Ji-Sang Park, Sunghyun Kim, Aron Walsh
We investigated stability and the electronic structure of extended defects including anti-site domain boundaries and stacking faults in the kesterite-structured semiconductors, Cu$…
A Finite-Size Supercell Correction Scheme for Charged Defects in One-Dimensional Systems
Sunghyun Kim, Ji-Sang Park, K. J. Chang
We propose a new finite-size correction scheme for the formation energy of charged defects and impurities in one-dimensional systems within density functional theory. The energy co…