Supporting Information

Carbon Dioxide Fischer-Tropsch Synthesis: A

New Path to Carbon-Neutral Fuels

Yo Han Choi a‡, Youn Jeong Jang b‡, Hunmin Park b, Won Young Kim b, Young Hye Lee b,

Sun Hee Choi c, Jae Sung Lee d *

a Division of Advanced Nuclear Engineering, Pohang University of Science and Technology

(POSTECH), Pohang 790-784, South Korea

b Department of Chemical Engineering, Pohang University of Science and Technology

(POSTECH), Pohang 790-784, South Korea

c Pohang Accelerator Laboratory, Pohang University of Science and Technology

(POSTECH), Pohang 790-784, South Korea

d School of Energy and Chemical Engineering, Ulsan National Institute of Science and

Technology (UNIST), Ulsan 689-798, South Korea

‡ These authors contributed equally to this work.

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Figure S1. (a) X-ray diffraction (XRD) patterns of CuFeO2 synthesized at different synthesis

times. (b) XRD patterns of reduced Fe2O3, CuFeO2-12, and CuFe2O4 in H2 flow at 400 OC for

2 h. The standard patterns of delafossite CuFeO2 and metallic Cu/Fe are shown in the bottom

of (a) and (b) panels, respectively.

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Figure S2. (a-c) SEM images of rhomboheral CuFeO2 crystals synthesized at different synthesis times of 6, 12 and 24 h. (d) CuFeO2-12 reduced by H2 treatment at 400 OC for 2 h (scale bar, 2.5μm). TEM images of reduced CuFeO2 -12 (e) and used CuFeO2 -12 (f).

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Figure S3. (a) Nitrogen adsorption-desorption isotherm and (b) pore size distribution (BJH)

of Fe2O3, CuFeO2 and CuFe2O4.

Figure S4. (a) Nitrogen adsorption-desorption isotherms and (b) BJH pore size distributions

of H2- CuFe2O4 and H2-CuFeO2.

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Figure S5. HAADF-STEM images of reduced CuFe2O4 (a, b), and the elemental mapping

images for iron (c) and copper (d) after the reaction.

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Figure S6. Carbon number distribution of liquid products from CO2 hydrogenation on

CuFeO2-derived catalyst obtained using a simulated distillation method. The reaction

conditions were 300 OC, 10 bars and a gas hourly space velocity (GHSV) of 1800 ml/g-h with

a H2/CO2 feed mole ratio of 3.

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Figure S7. A long term stability test of CO2 hydrogenation over CuFeO2-12 catalyst. The

reaction conditions were 300 OC, 10 bars and a gas hourly space velocity (GHSV) of 317

ml/g-h with a H2/CO2 feed mole ratio of 3.

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Figure S8. XPS spectra of Fe 2p and C 1s for used ex-CuFeO2 (a,c) and ex-CuFe2O4 (b,d)

catalysts after CO2 hydrogenation for 16 h .

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Figure S9. Crystal structures of (a) delafossite CuFeO2 made of alternating layers of [FeO6]

octahedral units and Cu(I) (red balls) (1) and (b) spinel CuFe2O4 structure with octahedral

(green) and tetrahedral units (purple) forming a cubic close packed lattice (2). Oxygen atoms

are represented in red.

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Figure S10. Cu K-edge XANES spectra of copper-based catalysts: (a) As-prepared state, (b)

reduced state, and (c) state after reaction.

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Table S1. BJH total pore volume, pore surface area and mean pore diameter for CuFeO2, H2-

CuFeO2, CuFe2O4 and H2-CuFe2O4.

Table S2. Summary of iron-based catalysts for CO2 hydrogenation

Table S3. Results of CO2 hydrogenation over ex-CuFeO2-12 with different GHSV.11

The reaction conditions were 300 OC, 10 bars and with a H2/CO2 feed mole ratio of 3.

Table S4. Hydrogenation of CO2, CO, and a mixed gas (CO2+CO) over ex-CuFeO2-12.

The reaction conditions were 300 OC, 10 bars and a gas hourly space velocity (GHSV) of 1800 ml/g-h with H2/CO2 or H2/CO feed mole ratio of 3.[a] CO2 conversion, CO selectivity, and CO-free hydrocarbon selectivity.[b] CO conversion, CO2 selectivity, and CO2-free hydrocarbon selectivity with a feed of 3CO2/CO/9H2.

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