Theory of photochemical reactions and catalysis near heterointerfaces and grain boundaries of semiconductor having defect segregations: Importance of space charge and Fermi level pinning

Description

Heterointerface formation and grain boundary engineering are widely used to control
chemical reactions of semiconductors in various applications, such as photochemical energy
production, bottom-up semiconductor processing, gas sensing. Especially, synergies of defect
engineering, composite formation, and morphology control, and grain boundary
density/direction in heterojunctioned nanomaterial systems can greatly increase the yield
amount of valuable chemicals through photocheimcal reactions. In many cases, however, the
materials design principles for single engineering factors are not valid anymore when multiple
materials engineering factors are applied simultaneously. Therefore, it is very challenging to
rationalize the strategies of multiple materials modification methods to achieve the highest
energy conversion efficiency. To solve this problem, we combined Fermi-Dirac statistics,
Maxwell-Boltzmann model, and density functional theory calculations and successfully
rationalized chemical reactions of nanomaterials having various engineering factors (doping,
morphology, grain boundary). In this presentation, I will introduce recent research works on
modeling method developments for atomic-layer deposition (ALD) in high mobility electron
transistor (HEMT), photochemical water splitting, and photocatalytic CO2RR of metalsemiconductor and metal-metal heterojunctions having multiple engineering factors.

Period	2 Jul 2025 → 4 Jul 2025
Event title	Nano Korea 2025
Event type	Conference
Location	Ilsan, Korea, Republic ofShow on map
Degree of Recognition	International