Catalytic Hydrogen Doping of NdNiO3 Thin Films under Electric Fields

ACS Appl Mater Interfaces. 2020 Dec 9;12(49):54955-54962. doi: 10.1021/acsami.0c15724. Epub 2020 Nov 26.

Abstract

The electric-field-assisted hydrogenation and corresponding resistance modulation of NdNiO3 (NNO) thin-film resistors were systematically studied as a function of temperature and dc electric bias. Catalytic Pt electrodes serve as triple-phase boundaries for hydrogen incorporation into a perovskite lattice. A kinetic model describing the relationship between resistance modulation and proton diffusion was proposed by considering the effect of the electric field during hydrogenation. An electric field, in addition to thermal activation, is demonstrated to effectively control the proton distribution along its gradient with an efficiency of ∼22% at 2 × 105 V/m. The combination of an electric field and gas-phase annealing is shown to enable the elegant control of the diffusional doping of complex oxides.

Keywords: electric-field-assisted hydrogenation; ionic-electronic doping; perovskite rare-earth nickelate thin film; phase transition; proton diffusion.