The synergistic effect of phosphomolybdic acid on rhodium-based metal–organic frameworks for the efficient selective photocatalytic reduction of CO 2 to CO

• Published in: New journal of chemistry 2021-04, Vol.45 (16), p.7344-7352
• Main Authors: Shan, Yurong, Liu, Dexiang, Xu, Chunyan, Zhan, Peng, Wang, Hui, Wang, Jing, He, Ren, Wang, Wenlei
• Format: Article
• Language: English
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/D0NJ06053D

In this work, PMA@NH 2 -MIL-68(Rh) with a mangosteen spherical structure was successfully synthesized by a hydrothermal method for the photocatalytic reduction of carbon dioxide. The electronic structure and morphology of PMA@NH 2 -MIL-68(Rh) composites were characterized using Fourier transform infrared spectrometer (FTIR), X-ray photoelectron spectroscopy (XPS), and UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS). Results showed that the 0.63% PMA@NH 2 -MIL-68(Rh) composite achieved the optimal catalytic performance, yielding 387.28 μmol·g −1 CO and 11.75 μmol·g −1 CH 4 . The production of CO by 0.63% PMA@NH 2 -MIL-68(Rh) was nearly fifteen times more than that by NH 2 -MIL-68(Rh). This prominent photocatalytic activity was caused by four active species, including photoelectrons (e − ), photo-holes (h − ), Mo 5+ and superoxide free radicals (˙O 2− ). The cycling and stability results showed that PMA@NH 2 -MIL-68(Rh) had no significant change in the photocatalytic degradation effect of CO 2 after five-time repeated, indicating that PMA@NH 2 -MIL-68(Rh) composites have acceptable stability.