The effect of support and promoters on the performance of Pt-based H2-SCR catalysts for NOx removal - Raw Data

H₂-combustion engines represent a promising alternative for achieving carbon neutrality. However, to efficiently remove the resulting NOx emissions, the current H₂-SCR technologies require a more in-depth understanding that will enable further catalyst improvements. In this context, this manuscript reports a systematic study on the effect of support and promoters on the H2-SCR performance of Pt-based catalysts. Parameters such as catalyst pre-treatment, noble metal loading, space velocity, and gas composition, were varied to elucidate their effects on the measured activity and selectivity profiles and to gain insight into the underlying reaction mechanism. A moderate interaction with the support and the formation of small Pt nanoparticles were identified as essential for NOx conversion at low temperatures. Accordingly, TiO₂-supported catalysts were found to be superior in terms of NOx conversion and N2 yield compared to the CeO₂-supported samples. Highly dispersed Pt species as present on strongly interacting supports are also highly sensitive to H2O and O2 inhibition. Acidic promoters increase the activity window, while basic dopants shift and narrow the NOx conversion window toward higher temperatures, the addition of acidic dopants results in the opposite effect. ... mehrNevertheless, the presence of basic sites on the catalyst surface improves the N2 selectivity over the operating temperature window and contribute to NH3 formation as secondary