Construction of NH2-UiO-66@PCN-224 Nanocomposites with Tightly Integrated Interfaces for Boosting Photocatalytic CO2 Reduction with H2O

Converting CO 2 into high-value-added products via “artificial photosynthesis” under mild conditions is a promising yet challenging strategy for developing efficient photocatalysts. This study reports a simple two-step solvothermal approach to fabricate the dual-metal–organic framework (MOF) nanocomposite NH 2 -UiO-66@PCN-224 (NU-66@PCN-224) with tightly integrated interfaces, which achieves efficient CO 2 to CO photocatalytic reduction under light irradiation. The epitaxially grown PCN-224, composed of Zr 6 clusters and tetrakis (4-carboxyphenyl) porphyrin (TCPP), serves as a shell layer and a visible light-absorbing antenna, thereby broadening the light absorption range of the composite material. Moreover, the tightly integrated interfaces of NU-66@PCN-224 enhance the mobility of photogenerated charge carriers, consequently enhancing its capability for CO 2 catalytic reduction. As a result, the combination of NU-66 and PCN-224 retains their individual advantages while achieving a synergistic enhancement of both adsorption and catalysis, further improving the photocatalytic performance. The as-prepared NU-66@PCN-224 catalyst exhibits outstanding photocatalytic performance, yielding 74.6 μmol g −1 h −1 of CO under irradiation without sacrificial agents or photosensitizers. This work demonstrates a straightforward and effective method for designing MOF-on-MOF photocatalysts with enhanced photoactivity.