摘 要: | Being abundant and active,Fe_2O_3 is suitable for selective oxidation of H_2S.However,its practical application is limited due to the poor sulfur selectivity and rapid deactivation.Herein,we report a facile template-free hydrothermal method to fabricate porous α-Fe_2O_3/SnO_2 composites with hierarchical nanoflower that can obviously improve the catalytic performance of Fe_2O_3.It was disclosed that the synergistic effect between α-Fe_2O_3 and SnO_2 promotes the physico-chemical properties of α-Fe_2O_3/SnO_2 composites.Specifically,the electron transfer between the Fe~(2+)/Fe~(3+) and Sn~(2+)/Sn~(4+) redox couples enhances the reducibility of α-Fe_2O_3/SnO_2 composites.The number of oxygen vacancies is improved when the Fe cations incorporate into SnO_2 structure,which facilitates the adsorption and activation of oxygen species.Additionally,the porous structure improves the accessibility of H_2 S to active sites.Among the composites,Fe1 Sn1 exhibits complete H_2 S conversion with 100% sulfur selectivity at 220℃,better than those of pure α-Fe_2O_3 and SnO_2.Moreover,Fe1 Sn1 catalyst shows high stability and water resistance.
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