Construction of high-performance catalysts for CO2 hydrogenation to aromatics with the assisted of DFT calculations.

We prepared ZnZr 7 O/HZ-1.5NH 4 F tandem catalyst with high catalytic activity for the direct conversion of CO 2 hydrogenation to aromatics by combining theoretical calculations and experiments. [Display omitted] • It was simulated that the (0 1 0) plane of the sheet HZSM-5 had the strongest adsorption capacity for CH 3 O* and CHOO*. • We prepared catalysts with high catalytic activity and stability by combining theoretical calculations and experiments. • The thickness can be precisely adjusted to prepare a series of sheet HZSM-5 by adding urea and NH 4 F. • Urea inhibits the generation of defective sites in HZSM-5, while NH 4 F promotes the generation of defective sites. • The thickness of the sheet HZSM-5 is also a factor affecting the catalytic activity. The adsorption properties of CH 3 O* and CHOO* adsorbed on the three crystal planes (0 0 1, 0 1 0, 1 0 1) of HZSM-5 were simulated by the generalized gradient approximation (GGA) of density functional theory (DFT), it was found that the (0 1 0) plane corresponding to the b-axis of the sheet HZSM-5 had the strongest adsorption energy for CH 3 O* and CHOO*. Therefore, we successfully synthesized sheet HZSM-5 with different thicknesses by adding the inhibitor (urea) and mineralizer (F−) to the synthesis system based on the theoretical calculations. The physicochemical properties of HZSM-5 were investigated by the characterization methods of SEM, TEM, Py-IR, OH-IR, CO 2 -TPD and so on. The results showed the thickness of HZSM-5 can be precisely adjusted by adding urea and NH 4 F and changing the ratio of urea/NH 4 F or TPAOH/NH 4 F. Then, the sheet HZSM-5 and ZnZr 7 O were connected in tandem to investigate the reaction conditions and catalytic performance for the direct conversion of CO 2 hydrogenation to aromatics. It was found that the HZ-1.5NH 4 F had a large specific surface area, suitable B acid content and more defect sites. These advantages resulted in a high aromatic selectivity of 77.5% and CO 2 conversion of 17.6% over ZnZr 7 O/HZ-1.5NH 4 F. Meanwhile, it exhibits stable performance and no significant deactivation after 80 h of operation. [ABSTRACT FROM AUTHOR]