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Abstract The electrification of the production of fine chemicals has received increased interest in combating petrochemical routes with a high carbon footprint. Oxidising biomass from waste streams with concomitant hydrogen production, such as the transformation of lignin to vanillin, would be a great asset. Here, we show the combination of activity screening using a scanning droplet cell on a thin‐film Ni−Fe library and performance testing in a flow‐through cell with pulse electrolysis. The identified optimal Ni−Fe material composition was prepared on Ni foam with a polymer/metal precursor spray method. Full factorial and Doehlert matrix designs were employed to better comprehend each parameter‘s effects on the complex system. The best conditions for the electrooxidation of Kraft lignin at room temperature were at E1st=1.36 V vs RHE, t1st=1 s for the first pulse and E2nd=1.60 V vs RHE and t2nd=15 s for the second pulse, leading to the significantly improved production of 2.15 μmols of vanillin at room temperature. Pulsed chronopotentiometry was demonstrated to be a cost‐effective and robust technique with a simple setup for the valorisation of Kraft lignin. Combined with a subsequent thermolysis step, 8.05 μmols of vanillin were obtained.

Abstract The production of green hydrogen may be greatly aided by the use of an alternative anode reaction replacing oxygen evolution to increase energy efficiency and concomitantly generate value‐added products. Lignin, a major component of plant matter, is accumulated in large amounts in the pulp and paper industry as waste. It has excellent potential as a source of aromatic compounds and can be transformed into the much more valuable aroma chemical vanillin by electrochemical depolymerisation. We used a flow‐through model electrolyser to evaluate electrocatalyst‐modified Ni foam electrodes prepared by a scalable spray‐polymer preparation method for oxidative lignin depolymerisation. We demonstrate how pulsing, i. e. continuously cycling between a lower and a higher applied current, increases the amount of formed vanillin while improving the energy efficiency. Further, we present a scanning droplet cell‐assisted high‐throughput screening approach to discover suitable catalyst materials for lignin electrooxidation considering that a suitable electrocatalyst should exhibit high activity for lignin depolymerization and simultaneously a low activity for vanillin oxidation and oxygen evolution. Combining electrosynthesis and electrocatalysis can aid in developing new customised materials for electrochemical processes of potential industrial interest.