Fe-based catalysts are widely used for CO_(2)hydrogenation to light olefins(C_(2–4)=);however,precise regulation of active phases and the balance between intermediate reactions remain significant challenges.Herein,we...Fe-based catalysts are widely used for CO_(2)hydrogenation to light olefins(C_(2–4)=);however,precise regulation of active phases and the balance between intermediate reactions remain significant challenges.Herein,we find that the addition of moderate amounts of Ti forms a strong interaction with Fe compositions,modulating the Fe_(3)O_(4)and Fe_(5)C_(2)contents.Enhanced interaction leads to an increased Fe_(5)C_(2)/Fe_(3)O_(4)ratio,which in turn enhances the adsorption of reactants and intermediates,promoting CO hydrogenation to unsaturated alkyl groups and facilitating C–C coupling.Furthermore,the strong Fe-Ti interaction induces the preferential growth of Fe_(5)C_(2)into prismatic structures that expose the(020),(–112),and(311)facets,forming compact active interfacial sites with Fe_(3)O_(4)nanoparticles.These facet and interfacial effects significantly promote the synergistic coupling of the reverse water gas shift and Fischer-Tropsch reactions.The optimized 3K/FeTi catalyst with the highest Fe_(5)C_(2)/Fe_(3)O_(4)ratio of 3.6 achieves a 52.2%CO_(2)conversion rate,with 44.5%selectivity for C2–4=and 9.5%for CO,and the highest space-time yield of 412.0 mg gcat^(–1)h^(–1)for C_(2–4)=.展开更多
Photothermal hydrogenation of carbon monoxide(CO)holds the potential to generate valuable C_(2+)chemicals using renewable solar energy.However,its activity and selectivity towards C_(2)—C_(3) alkanes are limited comp...Photothermal hydrogenation of carbon monoxide(CO)holds the potential to generate valuable C_(2+)chemicals using renewable solar energy.However,its activity and selectivity towards C_(2)—C_(3) alkanes are limited compared to conventional thermal catalysis.In this study,we developed a robust catalyst consisting of Cu/Fe_(3)O_(4) nanoparticles on Mo_(2)CT_(x) MXene,showing enhanced photothermal C_(2)—C_(3) production.The Cu component plays a crucial role in H_(2) dissociation and subsequent H spillover,facilitating the in situ generation of Fe^(0) in Fe_(5)C_(2) active sites and thus efficiently promoting photothermal CO hydrogenation.As a result,we achieved a 51.3%C_(2+)selectivity and 78.5%CO conversion at a high gas hourly space velocity(GHSV)of 12000 mL·gcat^(-1)·h^(-1) and 2.5 MPa in a flow reactor at 320℃.The overall C_(2)—C_(3) yield reached 23.6% with Cu/Fe_(3)O_(4)/Mo_(2)CT_(x) catalysts,marking a 2.8-fold increase compared to the performance of the bare Fe_(3)O_(4)/Mo_(2)CT_(x) catalyst.展开更多
文摘Fe-based catalysts are widely used for CO_(2)hydrogenation to light olefins(C_(2–4)=);however,precise regulation of active phases and the balance between intermediate reactions remain significant challenges.Herein,we find that the addition of moderate amounts of Ti forms a strong interaction with Fe compositions,modulating the Fe_(3)O_(4)and Fe_(5)C_(2)contents.Enhanced interaction leads to an increased Fe_(5)C_(2)/Fe_(3)O_(4)ratio,which in turn enhances the adsorption of reactants and intermediates,promoting CO hydrogenation to unsaturated alkyl groups and facilitating C–C coupling.Furthermore,the strong Fe-Ti interaction induces the preferential growth of Fe_(5)C_(2)into prismatic structures that expose the(020),(–112),and(311)facets,forming compact active interfacial sites with Fe_(3)O_(4)nanoparticles.These facet and interfacial effects significantly promote the synergistic coupling of the reverse water gas shift and Fischer-Tropsch reactions.The optimized 3K/FeTi catalyst with the highest Fe_(5)C_(2)/Fe_(3)O_(4)ratio of 3.6 achieves a 52.2%CO_(2)conversion rate,with 44.5%selectivity for C2–4=and 9.5%for CO,and the highest space-time yield of 412.0 mg gcat^(–1)h^(–1)for C_(2–4)=.
基金supported by the National Natural Science Foundation of China(Grant Nos.22272078,2240090130)the National Key Research and Development Program of the Ministry of Science and Technology of China(No.2020YFA0406102)the Frontiers Science Center for Critical Earth Material Cycling of Nanjing University,and the“Innovation and Entrepreneurship of Talentsplan"of Jiangsu Province。
文摘Photothermal hydrogenation of carbon monoxide(CO)holds the potential to generate valuable C_(2+)chemicals using renewable solar energy.However,its activity and selectivity towards C_(2)—C_(3) alkanes are limited compared to conventional thermal catalysis.In this study,we developed a robust catalyst consisting of Cu/Fe_(3)O_(4) nanoparticles on Mo_(2)CT_(x) MXene,showing enhanced photothermal C_(2)—C_(3) production.The Cu component plays a crucial role in H_(2) dissociation and subsequent H spillover,facilitating the in situ generation of Fe^(0) in Fe_(5)C_(2) active sites and thus efficiently promoting photothermal CO hydrogenation.As a result,we achieved a 51.3%C_(2+)selectivity and 78.5%CO conversion at a high gas hourly space velocity(GHSV)of 12000 mL·gcat^(-1)·h^(-1) and 2.5 MPa in a flow reactor at 320℃.The overall C_(2)—C_(3) yield reached 23.6% with Cu/Fe_(3)O_(4)/Mo_(2)CT_(x) catalysts,marking a 2.8-fold increase compared to the performance of the bare Fe_(3)O_(4)/Mo_(2)CT_(x) catalyst.
