Electronically Activated Fe₅C₂ via N-Doped Carbon to Enhance Photothermal Syngas Conversion to Light Olefins

Abstract

Solar-driven CO hydrogenation to light olefins holds great potential as a petroleum-independent process. Herein, a series of Fe5C2 loading on tunable N-doped carbon as photothermal catalysts are developed to achieve an efficient Fischer–Tropsch synthesis to olefin (FTO) reaction. Under light irradiation, the optimized catalyst delivers a selectivity of 55.3% for light olefins (CO2 free) at a CO conversion of 22.3%, showing 3.5 times the activity of pristine Fe5C2 catalyst. Experimental characterizations reveal electron transfer from the N atoms in support to the active phase of Fe5C2 to construct electron-rich active sites and therefore to boost the catalytic performance. N-concentration-dependent activity evaluation and density functional theory calculations ascertain that pyrrolic N plays a dominant role in promoting CO adsorption and activation. This study provides an alternative strategy of rational modulation of support to enhance solar-to-chemical conversion.

Enhancement of C5+ selectivity in photothermal Fischer–Tropsch synthesis by an inorganic heteropoly acid catalyst promotor

“…[11][12][13] Photothermal FTS mainly uses Ru, Co, Fe, and Ni as active components. 11,[14][15][16][17][18] Co has been applied in several photothermal catalytic systems because of its high activity, low cost and rich reserves. 19,20 Recently, Zhang and coworkers reported that Co-X-(ZnAl) catalysts (where X represents the reduction temperature) prepared by reducing ZnCoAl-layered-double-hydroxide (LDH) nanosheets show excellent photothermal conversion efficiency (15.4%) and higher light olefin (C 2-4 = ) selectivity (36.0%) under photothermal catalytic conditions.…”

Highly selective light olefin production via photothermal Fischer–Tropsch synthesis over α/γ-Fe2O3-derived Fe5C2 under low pressure

“…Fe 5 C 2 (1–3) represent the different occupied sites of Fe in the crystallographic structure of Fe 5 C 2 . 40 The similar XRD patterns and ratio of Fe 5 C 2 (1) : Fe 5 C 2 (2) : Fe 5 C 2 (3) from the Mössbauer spectra for α-C30A30 and α-Fe 2 O 3 after reaction indicate that the exposed crystal facets of Fe 5 C 2 are accompanied by similar interfaces (Fig. 4a and b).…”

Light‐Enhanced Conversion of CO2 to Light Olefins: Basis in Thermal Catalysis, Current Progress, and Future Prospects

“…Similar activities under both illuminated and dark (i.e., nonilluminated) conditions suggested the dominance of a thermal pathway where light acted as a source of heat. [ 162 ] In terms of Fe oxides, Li et al demonstrated that Fe–Fe 3 O 4 /ZnO–Al 2 O 3 could enable photothermal FTS that was enhanced by photogenerated charges. Under illumination (Xe lamp, 2 h, 5.0 W cm −2 ), a 20.9% CO conversion accompanied by light olefin selectivity at 42.4% (o/p = 4.7) could be achieved.…”