The Power of Interfaces: Fundamentals for Solid State Devices
The joint SOIFIT-Harverstore meeting was held at the historic Royal Society in London on10-11th March 2020.
The research interests of Skinner research group centre on the properties and structures of ion-conducting oxides, with emphasis on the identification and characterisation of new materials using in- situ high-temperature techniques such as x-ray and neutron powder diffraction techniques, secondary ion mass spectrometry and low energy ion scattering. This work has potential applications in the development of solid oxide fuel cell, electrolysis and permeation membranes and more have been identified as having application in the field of novel solid-state gas sensors.
Our Latest Publications
Here, we investigated the high temperature structural properties of the LaNb1–xWxO4+d (x = 0.04–0.16) family, which is a structural analogue of hyper-stoichiometric CeNbO4+d.
High oxide-ion conductivity through the interstitial oxygen site in Ba7Nb4MoO20-based hexagonal perovskite related oxides
We report oxide-ion conductors based on a hexagonal perovskite-related oxide Ba7Nb4MoO20. Ba7Nb3.9Mo1.1O20.05 shows a wide stability range and predominantly oxide-ion conduction in an oxygen partial pressure range from 2 × 10−26 to 1 atm at 600 °C. Surprisingly, its bulk conductivity, 5.8 × 10−4 S cm−1, is remarkably high at 310 °C, and higher than Bi2O3- and zirconia-based materials.
Theory of the Electrostatic Surface Potential and Intrinsic Dipole Moments at the Mixed Ionic Electronic Conductor (MIEC)-gas Interface
Using the theory of the electrostatic potential at the MIEC-gas interface as an electrochemical driving force, charge transfer at the ceria-gas interface has been modelled based on the intrinsic dipole potential of the adsorbate. This model gives a physically meaningful reason for the enhancement in electrochemical activity of a MIEC electrode as the steam and hydrogen pressure is increased in both fuel cell and electrolysis modes. This model was validated against operando XPS data from previous literature to accurately predict the outer work function shift of thin film Sm0.2Ce0.8O1.9 in a H2/H2O atmosphere as a function of overpotential.
Protonic Conduction in the BaNdInO4 Structure Achieved by Acceptor Doping
The potential of calcium-doped layered perovskite, BaNd1–xCaxInO4–x/2 (where x is the excess Ca content), as protonic conductors was experimentally investigated. The acceptor-doped ceramics exhibit improved total conductivities that were 1–2 orders of magnitude higher than those of the pristine material, BaNdInO4. The highest total conductivity of 2.6 × 10–3 S cm–1 was obtained in the BaNd0.8Ca0.2InO3.90 sample at a temperature of 750 °C in air. In humid air, this materia;l is a fast proton conductor.