Facilely fabrication of the direct Z-scheme heterojunction of NH2-UiO-66 and CeCO3OH for photocatalytic reduction of CO2 to CO and CH4.

[Display omitted] • A direct Z-scheme heterojunction of NU/CC was fabricated for CO 2 photoreduction. • The heterojunction of NH 2 -UiO-66/CeCO 3 OH was featured with O-Zr-CO 3 2- bond. • The rate of electron consumption of NU/CC is 152.8 μmol/g h, 5-fold of that of NU. NH 2 -UiO-66 is recently regarded as a potential photocatalyst for CO 2 reduction reaction due to the high CO 2 adsorption capacity, high UV–vis light absorption capacity and chemical stability. Aiming to further improve its activity, in this paper, a composite of NH 2 -UiO-66 and CeCO 3 OH (NU/CC) was fabricated via an in-situ growth method of NH 2 -UiO-66 on CeCO 3 OH. The X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electron spin resonance (ESR) characterizations indicated that a direct Z-scheme heterojunction between CeCO 3 OH and NH 2 -UiO-66 was formed via the formation of O-Zr-CO 3 2- bond. The CO 2 adsorption measurement, UV–vis DRS spectra and photo(electro)chemical measurements indicated that the optimal composite NU/CC-1.6–90 exhibited the higher CO 2 adsorption capacity, stronger respond and wider absorption range to UV–vis light, as well as the significantly delayed recombination of photogenerated electron-hole pairs, compared with other control samples. As a result, NU/CC-1.6–90 delivered the obviously enhanced photocatalytic activity of CO 2 to both CO and CH 4 , and the rate of electron consumption reached 152.8 μmol/g h, 5-fold of that of NH 2 -UiO-66. [ABSTRACT FROM AUTHOR]