First-Principles Study of Piezoelectric Properties and Bonding Analysis in (Mg, X, Al)N Solid Solutions (X = Nb, Ti, Zr, Hf)

Hirata, Kyoji; Yamada, Hiroshi; Uehara, Masato; Anggraini, Sri Ayu; Akiyama, Morito

doi:10.1021/acsomega.9b01912

Cited by 42 publications

(30 citation statements)

References 41 publications

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“…The enhancement in d 33 and d 33,f is mainly due to the softening of elastic constant C 33 and increase of e 33 as the concentration of co-dopants increases (shown in Figure 3(c,d)). Similar mechanism is observed in other dopants e.g., Sc [35] or other dopants [15,36,22]. Figure 1 indicates that these dopants lead the polar wurtzite structure close to a phase transition to non-polar hexagonal structure, which results in the softening of C 33 [35,12].…”

Section: Resultssupporting

confidence: 68%

“…The enhancement in d 33 and d 33, f is mainly due to the softening of elastic constant C 33 and increase of e 33 as the concentration of co-dopants increases (shown in Figure c,d). A similar mechanism is observed in other dopants, e.g., Sc or other dopants. ,, Figure indicates that these dopants lead the polar wurtzite structure close to a phase transition to nonpolar hexagonal structure, which results in the softening of C 33 . , , In fact, the energy difference between wurtzite and hexagonal phase (Δ E = E hexagonal – E wurtzite ) becomes significantly smaller with the co-doping or Sc concentrationshown in Figure e. This also indicates the energy proximity of the phase transition .…”

Section: Resultssupporting

confidence: 64%

“…17 Enhancement of piezoelectricity in several other quaternary alloys based on divalent and tetravalent cations in w-AlN (e.g., (Mg,Ti)AlN, 18,19 (Mg,Zr)AlN, 20,21 and (Zn,Ti)-AlN 19 ) has also been confirmed experimentally. Moreover, a giant increase of d 33 in w-AlN by co-doping of divalent Mg and pentavalent Nb has been predicted by the first-principles calculations 22 and also later confirmed experimentally. 23 The optimized atomic ratio between Nb 5+ and Mg 2+ ions in w-AlN is 1:2 for obtaining the best piezoelectric response 23 because this ratio ensures the charge neutrality.…”

Section: ■ Introductionmentioning

confidence: 57%

“…A similar mechanism is observed in other dopants, e.g., Sc 35 or other dopants. 15,22,36 Figure 1 indicates that these dopants lead the polar wurtzite structure close to a phase transition to nonpolar hexagonal structure, which results in the softening of C 33 . 12,3512,35 In fact, the energy difference between wurtzite and hexagonal phase (ΔE = E hexagonal − E wurtzite ) becomes significantly smaller with the co-doping or Sc concentration shown in Figure 3e.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

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Large Piezoelectric Response and Ferroelectricity in Li and V/Nb/Ta Co-Doped w-AlN

Noor‐A‐Alam

Olszewski

Campanella

et al. 2020

ACS Appl. Mater. Interfaces

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Based on density functional theory, we show that Li andX (X=V, Nb and Ta) co-doping in 1Li:1X ratio broadens thecompositional freedom for significant piezoelectric enhancement in w-AlN, promising them to be good alternatives of expensive Sc. Interestingly, these co-doped w-AlN also show quite large spontaneous electric polarization about 0.80 C/m2 with the possibility of ferroelectric polarization switching, opening new possibilities in wurtzite nitrides. Increase in piezoelectric stress constant (e33) with decrease in elastic constant ( C33 ) results enhancement in piezoelectric strain constant ( d33 ), which is desired for improving the performance of resonators for high frequency RF signals. Also, these co-doped w-AlN are potential lead-free piezoelectric materials for energy harvesting and sensors as they improve the longitudinal electromechanical coupling constant (K^2 33), transverse piezoelectric strain constant (d31), and figure of merit for power generation. However, the enhancement in K^2 33 is not as pronounced as that in d33, because co-doping increases the dielectric constant. The longitudinal acoustic wave velocity (7.09 km/s) of Li0.1875Ta0.1875Al0.625N is quite comparable with that of commercially used piezoelectric LiNbO3 or LiTaO3 in special cuts (about 5~7 km/s) despite the fact that the acoustic wave velocities drop with co-doping or Sc concentration. File list (2)download file view on ChemRxiv codoped-AlN.pdf (0.93 MiB) download file view on ChemRxiv codoped-

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Section: Resultssupporting

confidence: 68%

Section: Resultssupporting

confidence: 64%

Section: ■ Introductionmentioning

confidence: 57%

Section: ■ Results and Discussionmentioning

confidence: 99%

See 2 more Smart Citations

Large Piezoelectric Response and Ferroelectricity in Li and V/Nb/Ta Co-Doped w-AlN

Noor‐A‐Alam

Olszewski

Campanella

et al. 2020

ACS Appl. Mater. Interfaces

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“…The lower −ICOHP value indicates the weaker orbital hybridization in the LiO bond, which is a descriptor for the weaker bond strength. [ 44 ] Per Figure S33, Supporting Information, the −ICOHP for the LiO 1 bond in the Ru AC+SA configuration is lower than in the Ru SA configuration, in line with the conclusion derived from the atomic configuration. The more weakened LiO 1 bond makes the Li 2 C 2 O 4 dissociation easier thereby lowering the energy barrier of the rate‐determining step and enhancing the kinetics of the CO 2 ER process.…”

Section: Resultssupporting

confidence: 82%

Boosting Energy Efficiency and Stability of Li–CO₂ Batteries via Synergy between Ru Atom Clusters and Single‐Atom Ru–N₄ sites in the Electrocatalyst Cathode

et al. 2022

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climate change. [2] Many countries established legislations to limit the CO 2 emissions, targeting at carbon neutrality. [3] Meanwhile, efficient and clean battery systems are being developed. The lithium-ion battery (LIB) is the most successful and widely used system. [4] However, the relatively low energy density severely hindered the applications of LIBs. Recently, metalair batteries have attracted much attention due to their ultrahigh energy density. [5] However, most of them need to work in a pure oxygen environment. [6] Therefore, an energy-storage system directly utilizing CO 2 gas as redox medium is highly favorable.In 2013, Archer and co-workers proposed the concept of Li-CO 2 battery for CO 2 capture and energy storage, in which Li metal and CO 2 gas are the active materials in the anode and cathode side, respectively. [7] During discharge, Li + reacts with CO 2 to generate Li 2 CO 3 and carbon as discharge products, which is a CO 2 reduction reaction (CO 2 RR) process described as 4Li + + 3CO 2 + 4e − → 2Li 2 CO 3 + C. [8] In the reverse charging process, a CO 2 evolution reaction (CO 2 ER) occurs by decomposing Li 2 CO 3 into Li + and CO 2 gas. Many merits are identified for the Li-CO 2 battery system like the direct employing greenhouse gas of CO 2 and the high theoretical energy density of 1876 Wh kg −1 . [9] However, issues including but not limited to the large overpotential, poor cycling performance, and inferior rate capability significantly hinder the application of Li-CO 2 batteries. One dominating reason for these issues is the intrinsically sluggish kinetics of the CO 2 RR and CO 2 ER processes.Therefore, the key task for the practical application of Li-CO 2 batteries is to develop highly efficient catalysts toward the CO 2 RR and CO 2 ER. Large varieties of catalysts, such as carbon-based catalysts, [6,8a,b,10] single-metal-atom catalysts, [11] adjacent metal atoms catalyst, [12] nanostructured metal/alloy catalysts, [13] and transition metal compound catalysts [14] were developed for Li-CO 2 batteries to facilitate the CO 2 reduction and promote the decomposition of Li 2 CO 3 . Metallic ruthenium (Ru) and Ru-based materials is an important catalyst family for the CO 2 RR and CO 2 ER. [15] Ru catalyst has intrinsic advantage in The Li-CO 2 battery is a novel strategy for CO 2 capture and energy-storage applications. However, the sluggish CO 2 reduction and evolution reactions cause large overpotential and poor cycling performance. Herein, a new catalyst containing well-defined ruthenium (Ru) atomic clusters (Ru AC ) and single-atom Ru-N 4 (Ru SA ) composite sites on carbon nanobox substrate (Ru AC+SA @NCB) (NCB = nitrogen-doped carbon nanobox) is fabricated by utilizing the different complexation effects between the Ru cation and the amine group (NH 2 ) on carbon quantum dots or nitrogen moieties on NCB. Systematic experimental and theoretical investigations demonstrate the vital role of electronic synergy between Ru AC and Ru-N 4 in improving the electrocatalytic activity toward the C...

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Structural Stabilization and Piezoelectric Enhancement in Epitaxial (Ti₁₋_xMg_x)_0.25Al_0.75N(0001) Layers

Wang

Aryana

Gaskins

et al. 2020

Adv Funct Materials

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Epitaxial (Ti 1−x Mg x ) 0.25 Al 0.75 N(0001)/Al 2 O 3 (0001) layers are used as a model system to explore how Fermi-level engineering facilitates structural stabilization of a host matrix despite the intentional introduction of local bonding instabilities that enhance the piezoelectric response. The destabilizing octahedral bonding preference of Ti dopants and the preferred 0.67 nitrogen-to-Mg ratio for Mg dopants deteriorate the wurtzite AlN matrix for both Ti-rich (x < 0.2) and Mg-rich (x ≥ 0.9) alloys. Conversely, x = 0.5 leads to a stability peak with a minimum in the lattice constant ratio c/a which is caused by a Fermi-level shift into the bandgap and a trend towards non-directional ionic bonding, leading to a maximum in the expected piezoelectric stress constant e 33 . The refractive index and the sub-gap absorption decrease with x, the optical band gap increases, and the elastic constant along the hexagonal axis C 33 = 270±14 GPa remains composition independent, leading to an expected piezoelectric constant d 33 = 6.4 pC/N at x = 0.5 which is 50% larger than for the pure AlN matrix. Thus, contrary to the typical anti-correlation between stability and electromechanical coupling, the (Ti 1−x Mg x ) 0.25 Al 0.75 N system exhibits simultaneous maxima in the structural stability and the piezoelectric response at x = 0.5.

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First-Principles Study of Piezoelectric Properties and Bonding Analysis in (Mg, X, Al)N Solid Solutions (X = Nb, Ti, Zr, Hf)

Cited by 42 publications

References 41 publications

Large Piezoelectric Response and Ferroelectricity in Li and V/Nb/Ta Co-Doped w-AlN

Large Piezoelectric Response and Ferroelectricity in Li and V/Nb/Ta Co-Doped w-AlN

Boosting Energy Efficiency and Stability of Li–CO₂ Batteries via Synergy between Ru Atom Clusters and Single‐Atom Ru–N₄ sites in the Electrocatalyst Cathode

Structural Stabilization and Piezoelectric Enhancement in Epitaxial (Ti₁₋_xMg_x)_0.25Al_0.75N(0001) Layers

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First-Principles Study of Piezoelectric Properties and Bonding Analysis in (Mg, X, Al)N Solid Solutions (X = Nb, Ti, Zr, Hf)

Cited by 42 publications

References 41 publications

Large Piezoelectric Response and Ferroelectricity in Li and V/Nb/Ta Co-Doped w-AlN

Large Piezoelectric Response and Ferroelectricity in Li and V/Nb/Ta Co-Doped w-AlN

Boosting Energy Efficiency and Stability of Li–CO2 Batteries via Synergy between Ru Atom Clusters and Single‐Atom Ru–N4 sites in the Electrocatalyst Cathode

Structural Stabilization and Piezoelectric Enhancement in Epitaxial (Ti1−xMgx)0.25Al0.75N(0001) Layers

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Product

Resources

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Boosting Energy Efficiency and Stability of Li–CO₂ Batteries via Synergy between Ru Atom Clusters and Single‐Atom Ru–N₄ sites in the Electrocatalyst Cathode

Structural Stabilization and Piezoelectric Enhancement in Epitaxial (Ti₁₋_xMg_x)_0.25Al_0.75N(0001) Layers