Breaking the Conversion-Selectivity Trade-Off in Methanol Synthesis from CO<sub>2</sub> Using Dual Intimate Oxide/Metal Interfaces
Qimeng Sun, Xinyu Liu, Qingqing Gu, Zhihu Sun, Hengwei Wang, Lina Cao, Yuxing Xu, Shang Li, Bing Yang, Shiqiang Wei, Junling Lu
Abstract
The selective hydrogenation of carbon dioxide (CO 2 ) to value-added chemicals, e.g., methanol, using green hydrogen retrieved from renewable resources is a promising approach for CO 2 emission reduction and carbon resource utilization. However, this process suffers from the competing side reaction of reverse water–gas shift (RWGS) and methanol decomposition, which often leads to a strong conversion-selectivity trade-off and thus a poor methanol yield. Here, we report that InO x coating of PdCu bimetallic nanoparticles (NPs) to construct intimate InO x /Cu and InO x /PdIn dual interfaces enables the break of conversion-selectivity trade-off by achieving ∼80% methanol selectivity at ∼20% CO 2 conversion close to the thermodynamic limit, far superior to that of conventional metal catalysts with a single active metal/oxide interface. Comprehensive microscopic and spectroscopic characterization revealed that the InO x /PdIn interface favors the activation of CO 2 to formate, while the adjacent InO x /Cu interface readily converts formate intermediates to methoxy species in tandem, which thus cooperatively boosts methanol production. These findings of dual-interface synergies via oxide coating of bimetallic NPs open a new avenue to the design of active and selective catalysts for advanced catalysis.