Simultaneous Hydrogen Evolution and Lignin Depolymerization using NiSn Electrocatalysts in a Biomass-Depolarized Electrolyzer
Raziyeh Ghahremani, Fernando Farales, Fazel Bateni, John A. Staser
Abstract
In this paper, we report on our efforts to evaluate NiSn as anode electrocatalysts for simultaneous hydrogen evolution and lignin depolymerization in a biomass-depolarized electrolyzer. Different ratios of NiSn alloys were synthesized through co-electrodeposition of Ni and Sn from a pyrophosphate plating bath. The composition and morphology of the electrocatalysts were evaluated by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDS), and X-ray powder diffraction (XRD) techniques. Electrochemical measurements were carried out in a typical three electrode-cell system to evaluate electrocatalyst kinetics in 1.0 M NaOH solution. We evaluated the alloys as anode electrocatalysts in a flow-through biomass-depolarized electrolyzer. Gas chromatography-mass spectroscopy (GC-MS) was employed to evaluate the production rates of vanillin as one of the main oxidation products. It was found that using NiSn 20% electrode as the anode results in higher electrochemical reaction rates and potentially higher rate of aromatic products.