Ofuchi Yukino, Mitarai Kenta, Doi Sae, Saegusa Koki, Hayashi Mio, Sampei Hiroshi, Higo Takuma, Seo Jeong Gil, Sekine Yasushi
Department of Applied Chemistry, Waseda University 3-4-1, Okubo, Shinjuku Tokyo 169-8555 Japan
Research & Development Centre, Yanmar Holdings 2481, Umegahara Maibara Shiga 521-8511 Japan.
Chem Sci. 2024 Aug 27;15(37):15125-33. doi: 10.1039/d4sc04790g.
Ammonia, which can be decomposed on-site to produce CO-free H, is regarded as a promising hydrogen carrier because of its high hydrogen density, wide availability, and ease of transport. Unfortunately, ammonia decomposition requires high temperatures (>773 K) to achieve complete conversion, thereby hindering its practical applicability. Here, we demonstrate that high conversion can be achieved at markedly lower temperatures using an applied electric field along with a highly active and readily producible Ru/CeO catalyst. Applying an electric field lowers the apparent activation energies, promotes low-temperature conversion, and even surpasses equilibrium conversion at 398 K, thereby providing a feasible route to economically attractive hydrogen production. Experimentally obtained results and neural network potential studies revealed that this reaction proceeds HN-NH intermediate formation by virtue of surface protonics.
氨可在现场分解产生无CO的氢气,由于其氢密度高、来源广泛且易于运输,被视为一种有前景的氢载体。不幸的是,氨分解需要高温(>773 K)才能实现完全转化,从而阻碍了其实际应用。在此,我们证明,使用外加电场以及高活性且易于制备的Ru/CeO催化剂,可在明显更低的温度下实现高转化率。施加电场降低了表观活化能,促进了低温转化,甚至在398 K时超过了平衡转化率,从而提供了一条通往具有经济吸引力的制氢途径的可行路线。实验获得的结果和神经网络势能研究表明,该反应借助表面质子学形成HN-NH中间体。