Electrochromism in nickel-doped strontium titanate

Abstract

Electrochromism in SrTiO3 : Ni at 200–300°C has been investigated by electrical and optical measurements. (NiTiVO) ′ and Ni′Ti constitute the color centers on the cathode and anode sides, respectively. Oxygen vacancy drift determines the kinetics during the early state of coloration and during the entire process of bleaching. An activation energy of 0.95 eV for oxygen vacancy motion has been obtained from bleaching experiments.

Electrocoloration and oxygen vacancy mobility of BaTiO3

“…8 At this point, one may suspect that contrary to what has been stated in the beginning, the anodic color ͑Fig. 1͒ looks rather bluish than brown and the cathodic one ͑Fig.…”

“…2,[7][8][9] For the system of BaTiO 3 , there have been reports on the electrocoloration, [9][10][11][12][13][14][15] but the authors' main concern was mostly on the origins of color or the correlation of color change to the IR degradation ͑or conductivity change͒ rather than on the mobility itself, thus only a few scattered data on oxygen vacancy mobility are available. 5,6,9,10,13,15 As regards the electrocoloration of BaTiO 3 , it seems to have been generally agreed upon that a brown color emanates from the anode and a blue color from the cathode, 10,11,13 even though there are differences in shade depending on the authors and depending on observation temperatures.…”

Field-enhanced bulk conductivity and resistive-switching in Ca-doped BiFeO3 ceramics

“…Thus, it does not require oxide ion (or vacancy) transport, although this is suggested to be a key requirement in other memristive studies [23][24][25][26][27][28][29][30][31]. It does not require electron injection at the cathode, although evidence for this has been obtained from electrocolouration effects in other materials [23][24][25][26][27][28][29][30][31]. It does not require a cation-based mechanism for hole creation at The results reported here on Ca-doped BiFeO3 are different in nature but not in mechanism from that seen with various acceptor-doped titanate perovskites [17][18][19][20][21][22].…”

Voltage‐Dependent Bulk Resistivity of SrTiO3:Mg Ceramics

“…Dielectric ceramics containing oxygen vacancies, , incorporated by acceptor doping, show a slow increase in leakage current under dc field stress and with increasing temperature. This failure mechanism, known as resistance degradation, is believed to occur as a consequence of unmixing of the initially homogeneous concentration of oxygen vacancies . We present our interpretation of this model, which we term a memristive model for reasons discussed later, in Fig.…”

“…To understand these results, we consider first a widely accepted explanation for dc bias effects, primarily due to Waser et al . Dielectric ceramics containing oxygen vacancies, , incorporated by acceptor doping, show a slow increase in leakage current under dc field stress and with increasing temperature.…”