Tuning Metal‐Support Interaction and Surface Acidic Sites of Ni/Al2O3 by Dopamine Modification for Glycerol Steam Reforming

Abstract

AbstractIn this work, a universal dopamine modification strategy is used to improve the catalytic performance of Ni/Al2O3 for hydrogen production in glycerol steam reforming (GSR). Ni/Al2O3 showed poor catalytic stability with rapid deactivation after 8 h of reaction in GSR. Glycerol conversion and hydrogen selectivity were significantly higher for dopamine‐modified Ni/Al2O3 (by 98 % and 95 %, respectively) and this improved performance was maintained well for 21 h in the stability test. The protective carbon shell derived from dopamine was formed easily on the Ni/Al2O3 surface, the aggregation of Ni nanoparticles was inhibited, and the dispersion of Ni nanoparticles was improved. The electron‐donating effect of amino group to Ni2+ weakened the Ni‐Al2O3 interaction, and then promoted the reduction of the Ni species. In addition, the decrease in the number of strong acidic sites reduced the amount of carbon deposition on dopamine‐modified Ni/Al2O3. The moderate metal‐support interaction was more conducive to the formation of filamentous carbon, which collectively contributed to the increased catalytic stability of dopamine‐modified Ni/Al2O3. The facile dopamine‐modified method significantly improves the catalytic performance and can be generalized to other catalytic reaction that involve sintering and carbon deposition issues.