Kinetic Study of Photoelectrochemical Oxidation of Lignin Model Compounds on TiO₂ Nanotubes

Authors

Min Tian, Department of Chemistry, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario P7B 5E1, Canada;
Daniel Liba, Department of Chemistry, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario P7B 5E1, Canada;
Aicheng Chen, Department of Chemistry, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario P7B 5E1, Canada;Follow

Corresponding Author

Aicheng Chen(aicheng.chen@lakeheadu.ca)

Abstract

In this study, TiO₂ nanotubes were prepared via the electrochemical oxidation of titanium substrates in a non-aqueous electrolyte and their morphology and microstructures were examined by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The photoelectrochemical oxidation of two lignin model compounds, 1-(3,4-dimethoxyphenoxy)-2-(2-methoxyphenoxy)-1,3-propanediol (DMP) and 3-hydroxy-1-(3,4-dimethoxyphenoxy)-2-(2-methoxyphenoxy)-1,3-propanone (HDM), was investigated. A new band appeared at ~304 nm during the photoelectrochemical oxidation of DMP. The rate of DMP intermediate formation was amplified with the increase of initial concentrations, while it was diminished with increased temperature. Despite the similarity in structure between HDM and DMP, there are only small increases in absorbance during the oxidation of HDM, suggesting that HDM is less reactive. Quantum chemical calculations based on the density functional theory (DFT) were performed in order to link photoelectrochemical reactivity with specific molecular properties. Relatively higher ELUMO-EHOMO of HDM makes it more stable and thus more refractory to oxidation, which is consistent with our photoelectrochemical results.

Graphical Abstract

Keywords

Photoelectrochemical oxidation, TiO2 nanotubes, UV-Vis spectroscopy, lignin model compounds, DFT calculation

DOI Link

https://doi.org/10.61558/2993-074X.2622

Publication Date

2012-12-28

Online Available Date

2012-08-03

Revised Date

2012-07-31

Received Date

2012-06-18

Recommended Citation

Min Tian, Daniel Liba, Aicheng Chen. Kinetic Study of Photoelectrochemical Oxidation of Lignin Model Compounds on TiO₂ Nanotubes[J]. Journal of Electrochemistry, 2012 , 18(6): Article 6.
DOI: 10.61558/2993-074X.2622
Available at: https://jelectrochem.xmu.edu.cn/journal/vol18/iss6/6