MnO<sub>2</sub> Thin Film Electrodes for Enhanced Reliability of Thin Glass Capacitors

Akkopru-Akgun, Betul; Trolier-McKinstry, Susan; Lanagan, Michael T.

doi:10.1111/jace.13774

Cited by 16 publications

(5 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is interesting and relevant to note that the transition temperature for the transformation of Ba-stabilized α-MnO 2 to Mn 2 O 3 depends strongly on the Ba 2+ ion content, with the transition temperature varying from 600 to 675 °C when the Ba:Mn ratio varies between 0.04 and 0.1. 39 3.9. UV Raman Spectroscopy.…”

Section: Resultsmentioning

confidence: 99%

“…The combined XRD, TGA and DSC data therefore provide evidence that some oxygen is lost from the α-MnO 2 structure before the transformation to, and crystallization of Mn 2 O 3 occurs, thereby reducing the ability of the structurally modified, oxygen-deficient α-MnO 2 framework to reaccommodate water at temperatures above ∼400 °C. It is interesting and relevant to note that the transition temperature for the transformation of Ba-stabilized α-MnO 2 to Mn 2 O 3 depends strongly on the Ba 2+ ion content, with the transition temperature varying from 600 to 675 °C when the Ba:Mn ratio varies between 0.04 and 0.1 …”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Probing the Release and Uptake of Water in α-MnO₂·xH₂O

Yang¹,

Ford

Park³

et al. 2017

Chem. Mater.

View full text Add to dashboard Cite

is of interest as a cathode material for 3 V lithium batteries and as an electrode/electrocatalyst for higher energy, hybrid Li-ion/Li−O 2 systems. It has a structure with large tunnels that contain stabilizing cations such as Ba 2+ , K + , NH 4 + , and H 3 O + (or water, H 2 O). When stabilized by H 3 O + /H 2 O, the protons can be ion-exchanged with lithium to produce a Li 2 O-stabilized α-MnO 2 structure. It has been speculated that the electrocatalytic process in Li−O 2 cells may be linked to the removal of lithium and oxygen from the host α-MnO 2 structure during charge, and their reintroduction during discharge. In this investigation, hydrated α-MnO 2 was used, as a first step, to study the release and uptake of oxygen in α-MnO 2 . Temperature-resolved in situ synchrotron X-ray diffraction (XRD) revealed a nonlinear, two-stage, volume change profile, which with the aide of X-ray absorption near-edge spectroscopy (XANES), redox titration, and density functional theory (DFT) calculations, is interpreted as the release of water from the α-MnO 2 tunnels. The two stages correspond to H 2 O release from intercalated H 2 O species at lower temperatures and H 3 O + species at higher temperature. Thermogravimetric analysis confirmed the release of oxygen from α-MnO 2 in several stages during heating−including surface water, occluded water, and structural oxygen−and in situ UV resonance Raman spectroscopy corroborated the uptake and release of tunnel water by revealing small shifts in frequencies during the heating and cooling of α-MnO 2 . Finally, DFT calculations revealed the likelihood of disordered water species in binding sites in α-MnO 2 tunnels and a facile diffusion process.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Probing the Release and Uptake of Water in α-MnO₂·xH₂O

Yang¹,

Ford

Park³

et al. 2017

Chem. Mater.

View full text Add to dashboard Cite

show abstract

“…The positions of these modes are most easily identified in the Raman spectrum of the spent 3K Mn3O4 at approximately 398, 500, 551, and 576 cm −1 (Figure 10), and are assigned to cryptomelane [35][36][37]. While some peaks, such as the peak at 551 cm −1 , might be ascribed as hollandite MnO2 instead of cryptomelane, hollandite MnO2 presence is unlikely because it also has an intense Raman mode at ~700 cm −1 which is not observed in any of the sample sets [38]. Birnessite MnO2 presence is also not observed by Raman, since Birnessite has a sharp peak at ~740 cm −1 [39].…”

Section: Raman Spectroscopymentioning

confidence: 99%

Contrasting Effects of Potassium Addition on M3O4 (M = Co, Fe, and Mn) Oxides during Direct NO Decomposition Catalysis

Peck¹,

Roberts²,

Reddy³

2020

Catalysts

View full text Add to dashboard Cite

While the promotional effect of potassium on Co3O4 NO decomposition catalytic performance is established in the literature, it remains unknown if K is also a promoter of NO decomposition over similar simple first-row transition metal spinels like Mn3O4 and Fe3O4. Thus, potassium was impregnated (0.9–3.0 wt.%) on Co3O4, Mn3O4, and Fe3O4 and evaluated for NO decomposition reactivity from 400–650 °C. The activity of Co3O4 was strongly dependent on the amount of potassium present, with a maximum of ~0.18 [(µmol NO to N2) g−1 s−1] at 0.9 wt.% K. Without potassium, Fe3O4 exhibited deactivation with time-on-stream due to a non-catalytic chemical reaction with NO forming α-Fe2O3 (hematite), which is inactive for NO decomposition. Potassium addition led to some stabilization of Fe3O4, however, γ-Fe2O3 (maghemite) and a potassium–iron mixed oxide were also formed, and catalytic activity was only observed at 650 °C and was ~50× lower than 0.9 wt.% K on Co3O4. The addition of K to Mn3O4 led to formation of potassium–manganese mixed oxide phases, which became more prevalent after reaction and were nearly inactive for NO decomposition. Characterization of fresh and spent catalysts by scanning electron microscopy and energy dispersive X-ray analysis (SEM/EDX), in situ NO adsorption Fourier transform infrared spectroscopy, temperature programmed desorption techniques, X-ray powder diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) revealed the unique potassium promotion of Co3O4 for NO decomposition arises not only from modification of the interaction of the catalyst surface with NOx (increased potassium-nitrite formation), but also from an improved ability to desorb oxygen as product O2 while maintaining the integrity and purity of the spinel phase.

show abstract

“…4,5 In thin film form the dielectric strength increases considerably, partially due to one dimension being at nanoscale which allows a better heat dissipation, keeps trapping rate below the detrapping rate and decreases the probability of finding critical defect concentrations. 6,7 The nanoscale dimension may increase Young's modulus (𝑌) as the layer becomes thinner and results in elevated breakdown electric field as this parameter follows the relation, 𝐸 ∝ 𝑌 , where the exponent 𝑛 varies with thickness. 8 Basically, dielectric breakdown can be caused by a number of successive physical processes such as avalanche and field emission break, thermal breakdown produced by increasing conductance from Joule heating, an electromechanical collapse brought on by the attractive forces between electrodes, electrochemical deterioration, dendrite formation, etc.…”

mentioning

confidence: 99%

Ultrahigh capacitive energy storage in highly oriented Ba(ZrxTi1-x)O3 thin films prepared by pulsed laser deposition

Instan

Pavunny

Bhattarai

et al. 2017

Applied Physics Letters

View full text Add to dashboard Cite

We report structural, optical, temperature and frequency dependent dielectric, and energy storage properties of pulsed laser deposited (100) highly textured BaZr x Ti 1−x O 3 (x=0.3, 0.4 and 0.5) relaxor ferroelectric thin films on La 0.7 Sr 0.3 MnO 3 /MgO substrates which make this compound as a potential lead-free capacitive energy storage material for scalable electronic devices. A high dielectric constant of ~1400-3500 and a low dielectric loss of <0.025 were achieved at 10 kHz for all three compositions at ambient conditions. Ultrahigh stored and recoverable electrostatic energy densities as high as 214 ± 1 and 156 ± 1 J/cm 3 , respectively, were demonstrated at a sustained high electric field of ~3 MV/cm with an efficiency of 72.8 ± 0.6 % in optimum 30% Zr substituted BaTiO 3 composition.Future use of electricity generated from any renewable energy source will benefit greatly from advanced approaches to scalable capacitive energy storage module with a favorable figure for the power-to-mass ratio (specific power) including its usage in personal electronics,

show abstract

MnO₂ Thin Film Electrodes for Enhanced Reliability of Thin Glass Capacitors

Cited by 16 publications

References 48 publications

Probing the Release and Uptake of Water in α-MnO₂·xH₂O

Probing the Release and Uptake of Water in α-MnO₂·xH₂O

Contrasting Effects of Potassium Addition on M3O4 (M = Co, Fe, and Mn) Oxides during Direct NO Decomposition Catalysis

Ultrahigh capacitive energy storage in highly oriented Ba(ZrxTi1-x)O3 thin films prepared by pulsed laser deposition

Contact Info

Product

Resources

About

MnO2 Thin Film Electrodes for Enhanced Reliability of Thin Glass Capacitors

Cited by 16 publications

References 48 publications

Probing the Release and Uptake of Water in α-MnO2·xH2O

Probing the Release and Uptake of Water in α-MnO2·xH2O

Contrasting Effects of Potassium Addition on M3O4 (M = Co, Fe, and Mn) Oxides during Direct NO Decomposition Catalysis

Ultrahigh capacitive energy storage in highly oriented Ba(ZrxTi1-x)O3 thin films prepared by pulsed laser deposition

Contact Info

Product

Resources

About

MnO₂ Thin Film Electrodes for Enhanced Reliability of Thin Glass Capacitors

Probing the Release and Uptake of Water in α-MnO₂·xH₂O

Probing the Release and Uptake of Water in α-MnO₂·xH₂O