Bis-imidazolium Pd(0) based supported catalyst for the selective dehydrogenation of formic acid

The constant depletion of fossil feedstock, combined with their enormous impact on environmental health, has pushed the scientific community toward the definition of alternative energy sources. In this context, hydrogen has emerged as the elective “green choice”. Despite its huge potential as a sustainable fuel, its production remains an issue. In this context, liquid organic hydrogen carriers (LOHCs) are considered a viable alternative for the safe transport and in-situ production of hydrogen. In the present work, we report the achievements obtained on the generation of hydrogen from formic acid (FA), exploiting a bis-imidazolium Pd(0) based supported catalyst. The herein developed system proved to be particularly suitable in an aqueous environment due to its stable porous structure while demonstrating remarkable efficiency at high FA concentration (2.5 M) and under basic conditions, especially when NaOH was exploited to reach pH 9. These findings contribute to giving further insight into the correlation between catalyst structure and reactivity. The heightened activity in an alkaline environment was also a key aspect for a notable enhancement in the dehydrogenation rate, avoiding the possible dehydration pathway, which is generally favored at lower pH values. The sustainability of both the process and the catalyst has been further validated through its capacity for reusability, which has demonstrated consistent efficiency over five consecutive runs.