Fe促进的Pt@CeO_(2)催化剂用于CO_(2)加氢制C_(1)产品

Fe-promoted Pt@CeO_(2) Catalysts for CO_(2) Hydrogenation to C_(1) Products

在Pt@CeO_(2)核壳纳米球表面引入过渡金属助剂,探究了不同过渡金属的引入对其CO_(2)加氢性能的影响.研究结果表明,Fe物种的引入对加氢性能的提升效果最佳,液体C_(1)产率达到6.34×10^(-2) mmol·g^(-1)_(cat.)·h^(-1).透射电子显微镜(TEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)、N_(2)吸附-脱附实验、CO_(2)程序升温脱附(CO_(2)-TPD)和H_(2)程序升温还原(H_(2)-TPR)等表征结果表明,Fe物种在Pt@CeO_(2)表面均匀分散,且Fe的存在降低了Pt物种的电荷密度,产生了更多的Pt^(2+)物种,提高了产物中甲醇的选择性.此外,Fe的存在还促进了更多氧空位(O_(v))的形成,进而促进了对CO_(2)的吸附及后续的加氢反应,提高了催化活性.

Transition metal promoters were introduced on the surface of the Pt@CeO_(2) core@shell nanospheres,and the effects of different transition metals on the CO_(2) hydrogenation performance were investigated.The results show that the introduction of Fe species has the best effect on the enhancement of the hydrogenation performance,with a liquid C_(1) yield of 6.34×10^(−2) mmol·g^(-1) cat.·h^(−1).Transmission electron microscopy(TEM),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),N_(2) adsorption-desorption experiments,CO_(2) temperature-programmed desorption(CO_(2)-TPD),and H_(2) temperature-programmed reduction(H2-TPR)experiments reveal that Fe promoter was dispersed on the surface of Pt@CeO_(2),and Fe promoter decreases the charge density of Pt,generating more Pt2+species and improving the selectivity of methanol.In addition,it also facilitates the formation of more oxygen vacancies(O_(v)), which in turn facilitate the adsorption of CO_(2) as well as the subsequent hydrogenation reaction, and improve the catalytic activity.