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Article First-Principles Investigation of Kaolinite/YSZ Heterostructure for Solar-Driven Photocatalytic Hydrogen Production(Pergamon-Elsevier Science Ltd, 2025) Park, Jongee; Yu, Eunmi; Fatima, Syeda AfrinishThis work employs density functional theory (DFT) to elucidate the structural, electronic, and photocatalytic properties of a kaolinite/yttria-stabilized zirconia (Kaol/YSZ) heterostructure tailored for solar-driven hydrogen generation. The lattice mismatch between Kaol(001) and YSZ(111) was determined to be 4.4 % along the a-axis and 2.2 % along the b-axis. Two interface terminations were modeled: an O-terminated Si-O surface and an OH-terminated Al-OH surface. The OH-terminated interface demonstrated a stronger interfacial binding energy (-9.32 eV per cell) and enhanced thermodynamic stability, indicating its suitability for photocatalytic water splitting. Electronic structure analysis reveals that the Kaol/YSZ heterostructure exhibits a narrowed band gap of 1.46 eV relative to the isolated components, which promotes enhanced visible-light absorption. A type-II band alignment is observed, facilitating photoinduced electron transfer from the conduction band of YSZ to the conduction band of Kaol and promoting efficient charge separation. Hirshfeld charge analysis confirms the existence of a built-in electric field at the interface that further drives charge migration. Calculated optical absorption spectra shows a red shift in the heterostructure's absorption edge, extending its photoresponse into the visible region. Under simulated solar irradiation, photogenerated electrons preferentially migrate to Kaol for proton reduction, while holes remain on the YSZ surface to oxidize water, enabling simultaneous H2 evolution and O2 evolution pathways. These findings highlight the promise of the Kaol/YSZ heterostructure as a robust visible-light photocatalyst for sustainable hydrogen production and environmental remediation.Article Citation - WoS: 10Citation - Scopus: 10Computational Insight of Lithium Adsorption and Intercalation in Bilayer Tic3(Pergamon-elsevier Science Ltd, 2024) Park, Jongee; Fatima, Syeda AfrinishLithium-ion batteries (LIBs) have gained significant attention owing to their long lifespan. However, these batteries offer unmatched energy storage capacity and suffer from restricted lithium-ion mobility within the electrodes. Here, we employ first-principles calculation to investigate the two-dimensional TiC3 bilayer material. The results exhibit a remarkably high specific capacity of 1277 mAh/g and a low diffusion energy barrier of 0.12 eV. The TiC3 bilayer is anticipated to show high electrical conductivity, maintaining its metallicity due to strong bonding with four Li atoms. Additionally, its high thermal and dynamic stabilities are expected to significantly enhance the battery performance. Notably, the AB stacking bilayer TiC3 experiences a mere 6.01 % increase in volume, considerably smaller compared to the 28 % increase observed in the SiC bilayer. This suggests that TiC3 bilayers remain intact even at the highest concentration of lithium adsorptions. We also explored the solidelectrolyte interface (SEI) formation at the outset of battery operation using reactive force field molecular dynamics simulation. The reactive products of SEI are nicely matched with previous experimental and theoretical findings. All these intriguing properties position the TiC3 bilayer as an exceptionally promising material for use in LIBs.Article Citation - WoS: 51Citation - Scopus: 52A Dft Study of Tic3 as Anode Material for Li-Ion Batteries(Elsevier, 2023) Park, Jongee; Fatima, Syeda Afrinish; Afrinish Fatima, SyedaTwo-dimensional monolayer titanium carbide (TiC3) was used to study as a suitable electrode material for lithium-ion batteries with first principles calculation. The monolayer TiC3 showed excellent structural stability, high mechanical stiffness and good electronic conductance behaviour. The adsorption of Li on the carbon rich composition of titanium carbide monolayer is predicted to be favourable. TiC3 structure has remained the same, preserving its metallicity after Li adsorption with attaining high electrical conductivity during lithiation/delithiation process. Especially, the theoretical specific capacity of TiC3 monolayer is high, up to 1916 mAh/g, which is five times higher than the practical graphite. The low open circuit voltage (0.26 V) and diffusion energy barrier (0.25 eV) are also beneficial for overall performance of LIBs. Importantly, during lithiation the change in area is very small and reaches only 8.1 % for full lithiation indicating that it can avoid the large volume expansion during charge/discharge cycles. Its excellent performance, including high melting temperature, dynamical and mechanical stability, can be credited to the rigidness of the TiC3. Given these advantages, that is, high specific capacity, low Li diffusion energy barrier, low open circuit voltage and high in-plane stiffness, TiC3 monolayer can be a promising anode material for lithium-ion batteries.Article Citation - WoS: 8Citation - Scopus: 8Two-Dimensional Carbon Rich Titanium Carbide (tic3) as a High-Capacity Anode for Potassium Ion Battery(Elsevier, 2024) Fatima, Syeda Afrinish; Park, Jongee; Afrinish Fatima, SyedaIn recent years, two-dimensional (2D) materials, particularly MXenes such as titanium carbide, have gained significant interest for energy storage applications. This study explores the use of potassium-adsorbed TiC3 nanosheets as potential anode materials for potassium ion batteries (KIBs), utilizing first-principles calculations. The investigated electronic, mechanical, and thermal properties of TiC3 demonstrate its suitability as an anode material. The incorporation of potassium into the host material enhances electronic conductivity while maintaining a stable layered structure. Our findings reveal promising adsorption behavior of potassium in TiC3, leading to a high theoretical specific capacity of 958 mAh/g, coupled with a low energy barrier of 0.19 eV for potassium migration, which is indicative of superior electrochemical performance. Moreover, despite the high potassium content, the electrode material shows limited volume expansion of 11.3 %, suggesting good cyclability. Additionally, the equilibrium distance between potassium and TiC3, measured at 3.11 & ring;A, exceeds that of lithium and TiC3 (2.56 & ring;A), potentially augmenting the material's flexibility. Consequently, TiC3 emerges as a promising candidate for KIB anode materials.Article Citation - WoS: 6Citation - Scopus: 5Computational Analysis of Tic3 as a High-Efficiency Anode for Calcium-Ion Batteries(Elsevier, 2024) Park, Jongee; Fatima, Syeda AfrinishA comprehensive analysis of the structural, electronic, and thermal properties of TiC3 has been conducted. The calculated thermal expansion coefficient throughout a significant portion of the temperature range leads to a negative value underscoring the material's significance. The carbon-rich polytype of titanium carbide (TiC3) is being proposed for the first time as an anode material for calcium-ion batteries (CIB). The adsorption of Ca2+ ions has been determined to be favorable, with high accommodation of guest atoms and sufficiently rapid ionic mobility. The total volume expansion for a maximum Ca2+ adsorbed TiC3 configuration is calculated to be 8.2 %, which is lower compared to other anode materials for CIBs. Through the calciation of TiC3 up to the highest Ca2+ concentration (Ca7TiC3), an exceptionally high theoretical capacity of 2236 mAh/g has been achieved. Regarding battery rate capability, the lowest diffusion barrier calculated is 0.13 eV, with a remarkably high diffusion coefficient along the corresponding pathway equal to 10-3 cm2/s, indicating the ease of Ca ion movement within the host material. Furthermore, the equilibrium distance (2.5 & Aring;) between our host and guest atoms indicates a robust interaction between them. These findings lay the groundwork for the development of high-performance anode materials for CIBs.