چكيده لاتين
Hybrid plasma–catalytic technologies, as an innovative approach for CO₂ utilization and clean fuel production, hold remarkable potential for development and commercialization. One of the fundamental challenges in this field is enhancing the synergistic effect between plasma and catalysts, which can play a decisive role in improving process efficiency. However, while most previous studies have focused on designing catalytic compositions, the investigation of metal–organic frameworks (MOFs) and the use of cold plasma in this area have received comparatively less attention.
In this study, the CO₂ hydrogenation process under ambient temperature and pressure conditions was examined using a dielectric barrier discharge (DBD) plasma reactor and a series of single-metal MOF-74 catalysts (Co, Ni, Mg, Zn), bimetallic MOF-74 catalysts (Ni–Co, Co–Cu), a 4M MOF-74 structure, as well as single-metal and bimetallic ZIF-67 catalysts. These catalysts were synthesized and characterized using various analytical methods to investigate the synergistic effect between plasma and catalytic structures in converting CO₂ to methanol. Operational parameters, including gas flow rate and input voltage, were optimized to achieve the best performance. The optimal conditions were determined to be a flow rate of 60 mL/min and an input voltage of 10 kV.
Under these conditions, the single-metal and bimetallic ZIF-67 catalysts achieved CO₂ conversions of 9.69% and 3.90%, methanol selectivities of 1.84% and 1.98%, and energy efficiencies of 2.7 and 4.8 mmol/kJ, respectively. Among the MOF-74 family, Mg-MOF-74 exhibited favorable performance in CO₂ conversion and methanol production, while CoNi-MOF-74, with its strong synergistic effect, abundant active sites, and high stability, was identified as a promising candidate for industrial application. The 4M MOF-74 structure also achieved the highest methanol yield of 95% and an energy efficiency of 0.5 mmol/kJ.
Moreover, the specific input energy (SIE) was measured as a kinetic indicator, and its linear behavior confirmed the stability of the process under operational conditions. The catalysts also demonstrated reusability for up to six consecutive cycles without significant performance loss, indicating their durability and high stability.
The results of this study indicate that advanced MOF-based hybrid plasma–catalytic systems can serve as an effective and sustainable approach for converting CO₂ into valuable fuels such as methanol. These achievements, in addition to their scientific importance, offer substantial potential for reducing greenhouse gas emissions and advancing green, economically viable technologies for clean fuel production.
