Life-cycling and uncovering cation-trapping evidence of a monolithic inorganic electrochromic device: glass/ITO/WO₃/LiTaO₃/NiO/ITO

Abstract

The visualization of the microstructure change and of the depth of lithium transport inside a monolithic ElectroChromic Device (ECD) is realized using an innovative combined approach of Focused Ion Beam (FIB), Secondary Ion Mass Spectrometry (SIMS) and Glow Discharge Optical Emission Spectroscopy (GDOES). The electrochemical and optical properties of the all-thin-film inorganic ECD glass/ITO/WO3/LiTaO3/NiO/ITO, deposited by magnetron sputtering, are measured by cycling voltammetry and in situ transmittance analysis up to 11 270 cycles. A significant degradation corresponding to a decrease in the capacity of 71% after 2500 cycles and of 94% after 11 270 cycles is reported. The depth resolved microstructure evolution within the device, investigated by cross-sectional cutting with FIB, points out a progressive densification of the NiO layer upon cycling. The existence of irreversible Li ion trapping in NiO is illustrated through the comparison of the compositional distribution of the device after various cycles 0, 100, 1000, 5000 and 11 270. SIMS and GDOES depth profiles confirm an increase in the trapped Li content in NiO as the number of cycles increases. Therefore, the combination of lithium trapping and apparent morphological densification evolution in NiO is believed to account for the degradation of the ECD properties upon long term cycling of the ECD.

MXene-conducting polymer electrochromic microsupercapacitors

“…As with the high-rate performance, this fast switching speed can be attributed to the high conductivity and the uniform electric field distribution of the bottom-layer Ti 3 C 2 T x . In addition, the conducting PEDOT has a much higher conductivity than electrochromic transition metal oxides [23] such as WO 3 [6], NiO [41], and V 2 O 5 [42]. The cycle stability of the bleaching-coloration was shown in Figure S5b, which was tested by repeating the pulse voltage of ±0.6 V for 300 cycles.…”

Electrochromic Adaptability of NiOx Films Modified by Substrate Temperature in Aqueous and Non‐Aqueous Electrolytes

“…Heating the substrate cut down the quantities of nickel vacancy and promoted high transmittance, so there was no improved space for its bleached state. [ 70 ] Noteworthily, heating substrate gave a positive role in a long time Li‐ions based cycles, especially for NiO x ‐200. Increased transfer charge capacity has been seen because the crystalline structure provides enough and long‐term reactive sites for phase III (generation of Ni 4+ ).…”

Cation‐/Anion‐Based Physicochemical Mechanisms for Anodically Coloring Electrochromic Nickel Oxide Thin Films

“…Intelligent electronic devices are becoming indispensable, and will be more so in the future, in our daily life, due to the increasing use of digital automatic control processes. The popularity of smart windows, smartphones and driverless cars highly depend on the development of long-term durable ionexchange-based devices, e. g. electrochromic (EC) devices, [1][2][3] rechargeable electrical batteries [4] and supercapacitors. [5] However, most ion-based devices tend to lose their performance due to irreversible ion intercalations over time, [6] and it is not surprising that extensive studies have been conducted to improve the materials used in these ion-based devices.…”