Plasmon-enhanced hot-electron transfer in Ti-MOF-NH2@au@COF core-shell photocatalysts for visible-light-driven biodiesel production

Depleting fossil fuels drive the search for sustainable alternatives. Biodiesel is a greener substitute for petroleum diesel and can be used in diesel engines. Owing to their tunable structures, high surface area, and ordered porosity, MOFs and COFs are promising photocatalysts for biodiesel production. In this study, Ti-MOF-NH 2 @Au@COF core-shell nanocomposites incorporating intercalated Au nanoparticles between the Ti-MOF-NH 2 core and the COF shell were successfully fabricated and demonstrated enhanced activity and stability for visible-light-driven biodiesel production. Structural and morphological characterizations (XRD, FE-SEM, EDX, TEM, BET-BJH, Raman, UV–Vis) confirmed the successful formation of the hybrid material, with a high BET surface area of 892.6 m 2 g −1 . Incorporation of Au and COF broadened visible-light absorption and improved charge-carrier separation, leading to superior photocatalytic performance. Using oleic acid as a model feedstock, the optimized conditions delivered a 99% biodiesel yield at 3.86 wt% catalyst, a methanol/oleic acid ratio of 12:1, 25–30 °C, and 3 h irradiation. Additionally, the photocatalyst can be easily recovered and reused for five cycles. Overall, these results demonstrate an effective strategy for developing advanced MOF-COF hybrid photocatalysts for enhanced biodiesel production.