The synergy of Non-Thermal Plasma and functionalised Metal-Organic Frameworks: a case study in CO2 hydrogenation catalysis

• Applicant: Dr. Diletta Morelli Venturi, Ph.D.
• Subject Area: Solid State and Surface Chemistry, Material Synthesis
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 566210895

CO2 hydrogenation offers the dual benefit of reducing CO2 emissions while producing value-added chemicals that contribute to the transition to a net-zero economy. However, CO2 hydrogenation requires active and selective catalysts due to the thermodynamic stability of CO2 and the several different hydrogenation products. Metal-Organic Frameworks (MOFs) have been discussed as potential catalysts since their discovery due to their exceptional structural and compositional diversity, tuneable porosity and well-defined active sites, particularly in the selective adsorption of CO2. However, these properties could not be exploited to catalyse CO2 hydrogenation until now due to the insufficient thermal stability of MOFs at the required reaction temperatures. A significant decrease of the reaction temperature can be achieved by application of non-thermal plasma (NTP) conditions, opening an attractive field of application for MOFs. The combination of MOF catalysts, the CO2 hydrogenation process and NTP conditions has only recently emerged as a viable strategy. NTP is a promising way for the electrification of chemical processes and is characterised by the presence of reactive species already at low temperatures. It provides a unique platform for converting these excited species in the presence of a catalyst, which can be developed by exploiting the above-mentioned beneficial characteristics of MOFs. However, significant challenges remain in this area: a) The stability of MOFs under NTP conditions remains insufficiently studied, with limited information available. b) Studies that systematically compare different structural features and compositions of MOFs as NTP catalysts are still sparse and a no guide for catalyst development is yet available. c) The lack of reported cases limits the establishment of a comprehensive fundamental understanding of the MOF/NTP system. The aim of the project is to employ functionalised MOFs, based on Al, Zr, or Ce, to effectively capture CO2 with its following hydrogenation in H2-NTP treatment. The separation of the process into two steps, CO2 adsorption and plasma treatment, simplifies the whole process significantly and allows focused analysis of fundamental processes at the atomic/molecular level. By systematically exploring the stability and applicability of strategically designed MOFs in catalytic CO₂ hydrogenation reactions under NTP conditions, we will find trends to guide MOFs and NTP process development and open new windows of opportunities for future applications.

• DFG Programme: WBP Position