Solid-State Hydroxide Ion Conductivity in Silver(I) Oxide, Ag2O
[1];
[2];
[3];
[2];
[4];
[2];
[5]
- University of Pennsylvania, Philadelphia, PA (United States); University of Pennsylvania
- University of Pennsylvania, Philadelphia, PA (United States)
- Pennsylvania State University, University Park, PA (United States)
- Rensselaer Polytechnic Institute, Troy, NY (United States)
- University of Pennsylvania, Philadelphia, PA (United States); National Institute for Materials Science (NIMS), Ibaraki (Japan)
Silver (I) oxide, Ag2O, precipitated as microcrystals by combining aqueous silver(I) nitrate and KOH solutions, was found to be a solid-state hydroxide ion conductor with ionic conductivity on the order of 10-3 S/cm. The proton chemical shifts at 4.87 and -7.35 ppm measured by solid-state 1H-NMR experiments are attributed to water molecules and in-lattice OH- coordinated to silver, respectively. The lack of spinning sidebands around the 4.87 ppm peak indicates rapid reorientation on the NMR timescale, suggesting that the water molecules are adsorbed to the surface of the Ag2O crystals. Pulsed field gradient measurements gave similar diffusion coefficients (2 x 10-7 cm2/s at 298K) for all three proton environments indicating chemical exchange between sites on the millisecond timescale. The activation energy for OH- diffusion measured by NMR (0.18 eV) was comparable to that obtained by conductivity measurements and density functional theory (DFT) electronic structure calculations. Furthermore, the calculated Pourbaix diagram of Ag2O is consistent with the slightly lower sample density observed in He pycnometry and thermogravimetric measurements.
- Research Organization:
- University of Pennsylvania, Philadelphia, PA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF)
- Grant/Contract Number:
- AC02-05CH11231; SC0019281
- OSTI ID:
- 2496636
- Journal Information:
- Chemistry of Materials, Journal Name: Chemistry of Materials Journal Issue: 23 Vol. 36; ISSN 0897-4756
- Publisher:
- American Chemical Society (ACS)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Characterization of hydrous species in minerals by high-speed /sup 1/H MAS-NMR
Characterization of the primary hydration shell of the hydroxide ion with H2 tagging vibrational spectroscopy of the OH- ∙ (H2O)n=2,3 and OD- ∙ (D2O)n=2,3 clusters