Insights into the critical role of strong Metal-Support interaction in boosting liquid phase catalytic exchange performance of Pt/Ni-Al-LDHs catalysts

Liquid phase catalytic exchange (LPCE) for hydrogen isotope separation is an important method to deal with the tritiated waste water. In this work, a series of Pt/LDHs with varied Pt loadings are investigated comprehensively for the LPCE process. The catalyst preparation procedure is optimized with particular attention paid to the impact of thermal treatments. Without high-temperature calcination, the presence of residual chloride ions is revealed to significantly degrade LPCE performance and pose a corrosion risk. Therefore, a carefully tailored impregnation-calcination-reduction sequence is essential to obtain highly active catalysts. Furthermore, the effect of Pt loading is investigated by various characterizations and LPCE evaluation. The results demonstrate that the metal-support interface is effectively engineered over the low-loading (≤ 5 %) catalysts. Specifically, 1 wt% Pt/LDHs exhibits the highest column efficiency normalized by Pt weight, while 5 wt% Pt/LDHs exhibits the highest LPCE column efficiency. The excellent LPCE performances over the low-loading Pt/LDHs demonstrate the superiority of engineering the metal-support interface with a high degree of strong metal-support interaction (SMSI). These insights provide a fundamental understanding of the structure–activity relationship in Pt/LDHs catalysts for LPCE and offer valuable guidance for designing highly-efficient and cost-effective catalysts through engineering metal-support interface for isotopic exchange applications.