Thermodynamic stabilization of nanostructured alpha-Ni1−xCox(OH)2 for high efficiency batteries and devices

Abstract

The exceptional stability of FTO electrodes modified with Ni_1−xCo_x(OH)₂ in the alpha polymorphic phase was assigned to Co(II) substitution in the Ni(II) reticule, decreasing the basal plane distances and the average grain size, as confirmed by careful analyses of their X-ray diffractograms and thermal behavior as a function of the cobalt content. That phenomenon can be assigned to thermodynamic rather than kinetic factors, reflected by much higher dehydration/dehydroxilation temperatures, as expected for the stabilization of the mixed alpha-phase hydroxides in detriment of the oxides, opening real perspectives for application of alpha-Ni_1−xCo_x(OH)₂ in high efficiency batteries and devices.