Electronic Properties of Zn₂V_(1–x)Nb_xN₃ Alloys to Model Novel Materials for Light-Emitting Diodes

Abstract

We propose the Zn2V(1–x)Nb x N3 alloy as a new promising material for optoelectronic applications, in particular for light-emitting diodes (LEDs). We perform accurate electronic-structure calculations of the alloy for several concentrations x using density-functional theory with meta-GGA exchange–correlation functional TB09. The band gap is found to vary between 2.2 and 2.9 eV with varying V/Nb concentration. This range is suitable for developing bright LEDs with tunable band gap as potential replacements for the more expensive Ga(1–x)In(x)N systems. Effects of configurational disorder are taken into account by explicitly considering all possible distributions of the metal ions within the metal sublattice for the chosen supercells. We have evaluated the band gap’s nonlinear behavior (bowing) with variation of V/Nb concentration for two possible scenarios: (i) only the structure with the lowest total energy is present at each concentration and (ii) the structure with minimum band gap is present at each concentration, which corresponds to experimental conditions when also metastable structures are presents. We found that the bowing is about twice larger in the latter case. However, in both cases, the bowing parameter is found to be lower than 1 eV, which is about twice smaller than that in the widely used Ga(1–x)In(x)N alloy. Furthermore, we found that both crystal volume changes due to alloying and local effects (atomic relaxation and the V–N/Nb–N bonding difference) have important contributions to the band gap bowing in Zn2V(1–x)Nb x N3.

Carrier transport in bulk and two-dimensional Zn2(V,Nb,Ta)N3 ternary nitrides

“…The obtained lattice constants of the primitive unit cell of bulk Zn 2 VN 3 are a = 5.61 Å, b = 9.59 Å and c = 5.29 Å; of bulk Zn 2 NbN 3 are a = 5.79 Å, b = 9.88 Å and c = 5.42 Å; and of bulk Zn 2 TaN 3 are a = 5.79 Å, b = 9.90 Å and c = 5.44 Å, respectively. The results are match well with the available theoretical and experimental results for bulk Zn 2 VN 3 and Zn 2 NbN 3 42,45,67,68.…”

“…The results are match well with the available theoretical and experimental results for bulk Zn 2 VN 3 and Zn 2 NbN 3 . 42,45,67,68…”

Atomic insights into the interaction of N2, CO2, NH3, NO, and NO2 gas molecules with Zn2(V, Nb, Ta)N3 ternary nitride monolayers

“…The results obtained for the lattice constants are consistent with previous works. 20,21 The band structure plots of the Zn 2 (V, Nb, Ta)N 3 monolayers obtained using the GGA PBE and HSE06 approaches are shown in Fig. 1(d)-(f).…”

“…19 Another group of potentially stable Zn 2 V (1-x) Nb x N 3 ternary nitride compounds has been theoretically tested; within studied concentrations, 0 r x r 1, the Zn 2 V 0.5 Nb 0.5 N 3 compound turned out to be the most stable structure. 20 Very recently, following the strategy of aforementioned works, a new family of stable 2D materials, Zn 2 (V, Nb, Ta)N 3 monolayers, has been predicted. 21,22 All above-mentioned ternary nitrides, including 2D samples, hold high promise for application in optoelectronics and are, therefore, of interest for in-depth study.…”

Prediction of Zn2(V, Nb, Ta)N3 Monolayers for Optoelectronic Applications

“…A ITO/TiZnN 2 /Si photodetector has been developed generating a photocurrent with a low light intensity and insensitive to humidity . It has also been shown that Zn 2 V (1– x ) Nb x N 3 alloys possess comparably small bowing parameter that is beneficial for materials used in light-emitting diodes …”