Electrochromic(EC), nonstoichiometric NiOx thin films were made by reactive magnetron sputtering at low oxygen flow ratio(i.e., P=O2/Ar+O2≤10%). The results of optical spectral, x-ray diffraction spectrum, and x-ray photoelectron spectroscopy analyses indicate that the samples are oxygen(nickel)-deficient as P≤%4(≥%6), resulting in sub(over)-stoichiometry films. Spectroelectrochemical measurements show that the EC effect of NiOx in nonaqueous PC−LiClO4 electrolyte is direct correlation with the nickel vacancy concentration in films, while that in the aqueous KOH solution is nearly uninfluenced upon the change in stoichiometry as P≥%4. The films deposited at P=6% exhibit higher coloration efficiency of −25.3cm2C−1, larger ionic diffusion coefficient of −2.84×10−14m2s−1, and broader EC modulation span of 24% in PC−LiClO4 than the other ones. Based upon these values, EC devices featuring a WO3/PMMA−PC−LiClO4/NiOx structure and excellent performances were fabricated. We demonstrated that the nickel anodization should be responsible for the initial “activation” phenomena, which decreases(increases) the number of oxygen(nickel) vacancies. Moreover, the cause of degradation resulting from Li+-ion trapping in the IS layer was also clarified. This work provides a general framework for studying and designing superior EC devices, experimentally as well as theoretically.
Solar Energy Materials and Solar Cells – Elsevier
Published: May 1, 2018
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
All the latest content is available, no embargo periods.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud