| Summary: | The abundant C1 source CO<sub>2</sub> can be utilized to produce value-added chemicals through hydrogenation technology. A bifunctional catalyst consisting of reducible metal oxide Cr<sub>2</sub>O<sub>3</sub> and acidic zeolite ZSM-5 was designed for the direct conversion of CO<sub>2</sub> + H<sub>2</sub> into valuable aromatics, especially para-xylene (PX), via the methanol-mediated pathway. The twin structure of ZSM-5 (ZSM-5<sup>T</sup>), with sinusoidal channels that are predominantly exposed to the external surface, enhances the possibility of the transformation of methanol into PX due to the favorable diffusion dynamic of PX in the sinusoidal channels. Via the bifunctional catalyst Cr<sub>2</sub>O<sub>3</sub>&ZSM-5<sup>T</sup>, a PX selectivity of 28.7% and PX space-time yield (STY) of 2.5 g<sub>CH2</sub> h<sup>−1</sup> kg<sub>cat</sub><sup>−1</sup> are achieved at a CO<sub>2</sub> conversion rate of 16.5%. Furthermore, we rationally modify the ZSM-5<sup>T</sup> zeolite via Cu species doping and amorphous SiO<sub>2</sub> shell coating (Cu-ZSM-5<sup>T</sup>@SiO<sub>2</sub>). After combining with the Cr<sub>2</sub>O<sub>3</sub> catalytic component, the CO<sub>2</sub> conversion (18.4%) and PX selectivity (33.8%) are increased to some extent, which systematically increases the STY of PX to 3.0 g<sub>CH2</sub> h<sup>−1</sup> kg<sub>cat</sub><sup>−1</sup>. The physicochemical property of the acidic zeolite and the corresponding structure-function relationship in enhancing the PX productivity are discovered. Our work provides a novel catalyst design idea to boost PX synthesis performance from CO<sub>2</sub> hydrogenation.
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