The crystalline phase effect of zirconia provides a viable approach to investigate the interfacial sites of Ag/ZrO₂ catalysts in the hydrogenation of carbon–oxygen bonds. However, zirconia with different crystalline phases synthesised through general strategies faces the dilemma of ill-definition and huge structural differences, which present an insurmountable obstacle for the establishment of structure–activity relationships and the revelation of interfacial co-catalytic sites. This paper presents a novel synthetic strategy for the univariate modulation of zirconia crystalline phases. Compared with traditional strategies, the structure of zirconia synthesised by this strategy with different crystalline phases exhibits a high degree of similarity. Differently, the phase transition process endows monoclinic zirconia with a distinctive surface Zr³⁺–O_v site, which has been demonstrated to possess a robust adsorption capacity for carbon–oxygen bonds through in situ infrared spectroscopy and theoretical calculations. The coordination of surface Zr³⁺–O_v sites with silver sites capable of spilling hydrogen provides a novel interfacial co-catalytically active site-mediated reaction pathway for carbon–oxygen bond hydrogenation. The Ag/Zr–NH₄⁺ catalyst with this novel interfacial site exhibited excellent catalytic performance in the activity evaluation, with ethyl glycolate yields reaching 95.8%. The interfacial co-catalysis offers a novel reaction pathway and is anticipated to be applicable to other carbon–oxygen bonded hydrogenation systems.

中文翻译：

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Ag/ZrO2催化剂中氧化锆的晶相效应：氧空位介导的促进碳氧键加氢的新途径


氧化锆的晶相效应为研究Ag/ZrO ₂催化剂在碳-氧键氢化中的界面位点提供了一种可行的方法。然而，通过通用策略合成的不同晶相的氧化锆面临着结构不明确和结构差异巨大的困境，这给构效关系的建立和界面共催化位点的揭示带来了难以克服的障碍。本文提出了一种用于氧化锆晶相单变量调节的新颖合成策略。与传统策略相比，该策略合成的不同晶相的氧化锆的结构表现出高度的相似性。不同的是，相变过程赋予单斜氧化锆独特的表面Zr ³⁺ -O _v位点，通过原位红外光谱和理论计算证明其对碳-氧键具有强大的吸附能力。表面Zr ³⁺ -O _v位点与能够逸出氢的银位点的配位为碳-氧键氢化提供了一种新型的界面共催化活性位点介导的反应途径。具有这种新型界面位点的Ag/Zr–NH ₄ ⁺催化剂在活性评价中表现出优异的催化性能，乙醇酸乙酯收率达到95.8%。 界面共催化提供了一种新颖的反应途径，预计适用于其他碳-氧键合氢化系统。