Sustainable synthesis of a new semiamorphous Ti-BDC MOF material and the photocatalytic performance of its ternary composites with Ag3PO4 and g-C3N4

Abstract

Ti-MOFs have significant research and industrial demand due to their extraordinary photocatalytic potential. However, the number of known Ti-MOFs is quite limited compared to other high-valent based MOFs. In this work, we present a new Ti-MOF, prepared under environmental, energetic and economical (3E) sustainable conditions and which is potentially scalable, as it is quickly prepared at room temperature, which makes it competitive with the widely used conventional MIL-125(Ti). Moreover, novel Ti-BDC based ternary photocatalysts were successfully prepared by mixing Ti-BDC with g-C3N4 and Ag3PO4. These composites reduce the shortcoming associated with visible light absorption, recombination, and the transfer of photogenerated charges of Ti-BDC. They possess high surface interaction between the three components, high solar to chemical energy conversion and excellent photocatalytic performance in the degradation of methyl orange (94% in 90 min and 99% in 60 min when exposed to indoor or outdoor systems, respectively) due to multi-structural and synergistic effects. Importantly, the catalytic efficiency did not decrease significantly even after the fourth reaction cycles, showing its good stability and recyclability. Moreover, the presence of Ag0 will knock a new insight in the photo-excited charge carrier transfer from conventional to Z-scheme mechanisms.