FeO–CeO2 nanocomposites: an efficient and highly selective catalyst system for photothermal CO2 reduction to CO

Abstract

Solar-driven catalysis is a promising strategy for transforming CO 2 into fuels and valuable chemical feedstocks, with current research focusing primarily on increasing CO 2 conversion efficiency and product selectivity. Herein, a series of FeO-CeO 2 nanocomposite catalysts were successfully prepared by H 2 reduction of Fe(OH) 3 -Ce(OH) 3 precursors at temperatures (x) ranging from 200 to 600°C (the obtained catalysts are denoted as FeCe-x). An FeCe-300 catalyst with an Fe:Ce molar ratio of 2:1 demonstrated outstanding performance for photothermal CO 2 conversion to CO in the presence of H 2 under Xe lamp irradiation (CO 2 conversion, 43.63%; CO selectivity, 99.87%; CO production rate, 19.61 mmol h −1 g cat −1; stable operation over 50 h). Characterization studies using powder X-ray diffraction and highresolution transmission electron microscopy determined that the active catalyst comprises FeO and CeO 2 nanoparticles. The selectivity to CO of the FeCe-x catalysts decreased as the reduction temperature (x) increased in the range of 300-500°C due to the appearance of metallic Fe 0 , which introduced an additional reaction pathway for the production of CH 4 . In situ diffuse reflectance infrared Fourier transform spectroscopy identified formate, bicarbonate and methanol as important reaction intermediates during light-driven CO 2 hydrogenation over the FeCe-x catalysts, providing key mechanistic information needed to explain the product distributions of CO 2 hydrogenation on the different catalysts.

Gallium nitride catalyzed the direct hydrogenation of carbon dioxide to dimethyl ether as primary product

“…12 ), which can be assigned to the characteristic C–H bond vibrations of the absorbed DME. According to the references 28 – 30 , CO 3 2– and HCO 3 – species are likely intermediates for the formation of CO via the RWGS reaction. Moreover, the HCOO * species are important intermediates for the formation of oxygenates during the CO 2 hydrogenation 31 , 32 .…”

Photothermal Chemistry Based on Solar Energy: From Synergistic Effects to Practical Applications

“…We have summarized a number of representative PTC works involving different fields, as shown in Table 1 . [ 33,36,38‐47,49‐57,61‐68,70‐73,75‐81,83,85,87‐89,94,111‐113,115,117,118,120,121,123‐168 ] The PTC works are categorized into three major fields, solar fuel production, chemical synthesis, and environmental remediation, and the catalysts and energy sources used in the studies, along with the reaction temperatures and reaction results are collected. Besides, the datasets of the temperatures and the reaction results have been extracted and plotted for better visibility, as shown in Figure .…”

Powering the next industrial revolution: transitioning from nonrenewable energy to solar fuelsviaCO2reduction

“…The temperature dependence on the preparation of the photocatalyst was studied by Zhao et al in the photothermal generation of CO by a FeO–CeO 2 nanocatalyst. 71 Fe(OH) 3 –Ce(OH) 3 precursors were reduced using H 2 in the range of 200–600 °C, yielding the nanocomposite catalysts. The material prepared with a 2 : 1 ratio of Fe : Ce at 300 °C (Fe 2 Ce1-300) showed the greatest activity, with a CO 2 conversion of 43.63%, CO selectivity of 99.98%, and a reaction rate of 19.61 μmol g −1 h −1 .…”