Herein, we report high-performance Pd and Ca-promoted Pd nanoparticles (NPs) (~2–6 nm) over mesoporous CeO₂ with dual functionality of converting CO₂ to methanol and its dehydration to di-methyl ether (DME) in a single catalyst bed prepared by a single-pot sol–gel chelating (SGC) method. Moreover, Ca promotion (0.5wt. %, optimized value) greatly improved the catalytic performance (X_CO2: 30.5 %, S_DME: 70.5 % and space time yield (STY_DME): 5276 mmol/kgcat.hr at 325 °C and 20 Bar) by increasing Pd⁰ content over CeO₂ and tuned the redox properties of CeO₂ as well as basicity/acidity of tested samples as evidenced by the characterization results. In situ diffuse reflectance infrared fourier transform spectroscopy (DRIFTS) provided insights of the formation of DME and CH₄ with visible respective IR bands along with the identification of various transient surface species emerged over the catalyst surface at actual reaction conditions which led us to propose a reaction mechanism following a formate route to methanol and its subsequent dehydration to dimethyl ether.

在此，我们报告了在介孔 CeO ₂上的高性能 Pd 和 Ca 促进的 Pd 纳米粒子（NPs）（~2-6 nm），具有将 CO ₂转化为甲醇及其脱水为二甲醚（DME）的双重功能。通过单锅溶胶-凝胶螯合（SGC）方法制备的单催化剂床。此外，Ca 促进（0.5wt. %，优化值）大大提高了催化性能（X _CO2：30.5 %，S _DME：70.5 % 和时空产率（STY _DME）：5276 mmol/kgcat.hr at 325 °C 和20巴）通过增加的Pd ⁰内容在CeO ₂和调谐的CeO的氧化还原性质₂以及表征结果所证明的测试样品的碱度/酸度。原位漫反射红外傅立叶变换光谱 (DRIFTS) 提供了对 DME 和 CH ₄形成的见解，并提供了各自可见的红外波段，以及在实际反应条件下催化剂表面出现的各种瞬态表面物种的鉴定，这使我们提出了一个反应机理遵循甲酸盐路线生成甲醇并随后脱水生成二甲醚。