Liu Li, Lv Pingli
State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology (Shandong Academy of Sciences) Jinan 250353 China
School of Light Industry and Engineering, Qilu University of Technology (Shandong Academy of Sciences) Jinan 250353 China.
RSC Adv. 2021 May 12;11(28):17391-17398. doi: 10.1039/d1ra01724a. eCollection 2021 May 6.
In order to improve the photocatalytic activity of a bimetallic cocatalyst, understanding its mechanism is very important for the development of a CO photocatalyst. In this study, density functional theory (DFT) calculations were performed to investigate CO adsorption and dissociation over Pd-Cu bimetallic clusters loaded on a TiO(101) surface, aiming at understanding the origin of the effect caused by the presence of Cu. The results demonstrated that the introduction of a Cu atom has a dual effect on the adsorption and dissociation of CO: (1) it provides the positive polarization charge center to enhance CO adsorption, and (2) it up-shifts the d-band center of the Cu atom to improve the activation of CO. Thus, the activity of the PdCu/TiO(101) surface, as compared with that of the Pd/TiO(101) surface, can be significantly improved, and the active center is the introduced Cu atom. This result is not only helpful for the development of effective CO photocatalysts but also crucial to understand the basic mechanism of bimetallic catalysis.
为了提高双金属助催化剂的光催化活性，了解其作用机制对于开发CO光催化剂非常重要。在本研究中，进行了密度泛函理论（DFT）计算，以研究负载在TiO(101)表面的Pd-Cu双金属簇上的CO吸附和解离，旨在了解Cu的存在所产生效应的起源。结果表明，引入Cu原子对CO的吸附和解离具有双重作用：（1）它提供正极化电荷中心以增强CO吸附，（2）它使Cu原子的d带中心上移以改善CO的活化。因此，与Pd/TiO(101)表面相比，PdCu/TiO(101)表面的活性可得到显著提高，且活性中心是引入的Cu原子。这一结果不仅有助于开发有效的CO光催化剂，而且对于理解双金属催化的基本机制也至关重要。
