Abstract

The intercalation of cations into electrodeposited nickel hexacyanoferrate (NiHCF) depends on the stoichiometry and oxidation state of the material. To better understand this material's performance as a cation separation matrix, the oxidation state needs to be measured independently from the stoichiometry, regardless of the particular intercalated cation. Reported is the use of Raman spectroscopy to quantify the absolute oxidation state of NiHCF thin films. Raman spectroscopy probes NiHCF's cyanide bonds, which are sensitive to the oxidation state of the matrix. The oxidation state is controlled via potentiostatic experiments in electrolytes containing Na⁺, K⁺, and Cs⁺ (NO₃^- is the common anion). Principal component analysis (PCA) on the Raman spectra shows that more than 90% of the spectral variance is captured by one principal component, with a score value shown to be directly related to the oxidation state of the film. A universal, predictive regression model was developed using these score values as the dependent variables and Raman spectra as the independent variables. The results were confirmed with electrochemistry and energy dispersive X-ray spectroscopy.

Optically-controlled digital electrodeposition of thin-film metals for fabrication of nano-devices

Na Liu, Fanan Wei, Lianqing Liu, Hok Sum Sam Lai, Haibo Yu, Yuechao Wang, Gwo-Bin Lee, and Wen J. Li
Opt. Mater. Express 5(4) 838-848 (2015)

Study of surface roughness of nickel electrodeposits

J. Palmari, G. Rasigni, M. Rasigni, J. P. Palmari, A. Hugot-le Goff, and A. Llebaria
J. Opt. Soc. Am. A 3(4) 410-416 (1986)

Room-temperature deposition of amorphous titanium dioxide thin film with high refractive index by a filtered cathodic vacuum arc technique

Zhiwei Zhao, Beng Kang Tay, and Guoqing Yu
Appl. Opt. 43(6) 1281-1285 (2004)

Electrochromic switching of monolithic Prussian blue thin film devices

Jianxi Liu, Wencai Zhou, Stefan Walheim, Zhengbang Wang, Peter Lindemann, Stefan Heissler, Jinxuan Liu, Peter G. Weidler, Thomas Schimmel, Christof Wöll, and Engelbert Redel
Opt. Express 23(11) 13725-13733 (2015)

Raman spectroscopy of Cu-Sn-S ternary compound thin films prepared by the low-cost spray-pyrolysis technique

Viktor V. Brus, Ivan S. Babichuk, Ivan G. Orletskyi, Pavlo D. Maryanchuk, Volodymyr O. Yukhymchuk, Volodymyr M. Dzhagan, Igor B. Yanchuk, Mykhailo M. Solovan, and Iryna V. Babichuk
Appl. Opt. 55(12) B158-B162 (2016)