First-Principles Studies on Structural, Electronic and Optical Properties of Fe-doped Nis2 Counter Electrode for Dye-Sensitized Solar Cells using Dft+U

Abstract

The structural, electronic and optical properties of nickel disulfide (NiS2) and iron (Fe)-doped NiS2 were computed by using first-principles calculations through the density functional theory (DFT) method. The Fe was used as a dopant element to understand the behavior and the key mechanism of Fe-doped NiS2 as a counter electrode in dye-sensitized solar cells (DSSC). The results indicated that the structural properties of the NiS2 as the cubic crystal structure with the space group Pa3 (205) (pyrite structure type) agree with experimental data. The density of states (DOS) of NiS2 and Fe-doped NiS2 shows a gapless bandgap due to Mott insulator behavior. As for optical properties, the optical absorption of NiS2 is shifted towards the infrared (IR) region when doping with Fe while the conductivity of Fe-doped NiS2 is slightly higher in conductivity. These optical properties show that Fe-doped NiS2 is good for photocatalytic activity and may provide an excellent electron charge transfer for a counter electrode in DSSC

Molybdenum-Doped Nickel Disulfide (NiS2:Mo) Microspheres as an Active Anode Material for High-Performance Durable Lithium-Ion Batteries

“…In addition, partial amorphization of MoO 3 during initial cycling could also lead to an increase in the Li + ion diffusion kinetics, providing more accessible active sites for Li + insertion, and hence causing a gradual increase of the specific capacity. Similar cycling-induced capacity gain has been previously observed for MoO 3 -based anode materials. , Interestingly, the NiS 2 :Mo (5%) microsphere electrode delivered an exceptionally high initial specific capacity of 900 mAh g –1 , which exceeded the theoretically predicted specific capacity value of NiS 2 (807 mAh g –1 ), as well as previously reported specific capacity values for the TMO/TMS-based anode materials, as shown in Table . ,,− Even though the specific capacity of the electrode decreased gradually up to 50 th cycle, it retained a high reversible capacity of 713.3 mAh g –1 even after 120 cycles, with CE as high as 98.43%.…”

“…Based on the XRD results, the Mo site occupancy in the unit cell of NiS 2 is proposed. NiS 2 bears a cubic crystal structure with the space group Pa 3 (205), in which the Ni atoms occupy the sites in the fcc sublattice (Figure B) . The doped Mo atoms incorporate into the NiS 2 lattice, possibly by replacing the Ni 2+ ions in the {111} and {311} lattice planes as displayed in Figure C.…”

Structural, electronic and optical properties of chromium carbide (Cr3C) as potential counter electrode material: a first principle study

“…The dielectric constant of the compound at high frequency along perpendicular Ꜫ (∞) direction was found to be 100.00. In both cases, these results indicate that the material could have a greater performance of the excellent efficiency in light harvesting for DSSC (Malik et al, 2020). Figure 3(b) presents the real part of the dielectric function of Cr3C, we noticed the presence of prominent peaks at z-z direction, and the prominent peak is at -150.00.…”