Dynamic evolution of higher alcohols from CO2 on Fe3O4-Fe5C2-Cu catalytic interfaces with amorphous Ti layout
摘要
Selective synthesis of alcohols from carbon-based feedstocks remains a fundamental challenge due to complex reaction networks and competing pathways. Here we report a titanium iron ore material FeTiOx synthesized via a high-temperature calcination strategy that introduces amorphous Ti species into the catalyst framework. The FeTiOx system exhibits an intrinsic preference for higher alcohols formation, and tuning the dispersion of Cu species further enhances higher alcohols selectivity to 30.2%, while maintaining a CO2 conversion of 42.5%. Operando X-ray diffraction and diffuse reflectance Fourier transform infrared spectroscopy are employed to monitor the evolution of the catalyst phase structure (Fe2O3 → Fe3O4 → Fe5C2) and chemical intermediates (CO*, CHx*, CH3CH2O*) in real time, thereby elucidating the dynamic evolutions of the catalyst phases and surface intermediates under reaction conditions. These results uncover the structural adaptability of the catalyst and its role in regulating key reaction intermediates. This work highlights the importance of phase-structure engineering in Fe-based catalytic systems and provides a strategy for designing efficient catalysts for selective higher alcohols synthesis.