Density Functional Theory Study of a Graphdiyne-Supported Single Au Atom Catalyst for Highly Efficient Acetylene Hydrochlorination

Abstract

In this work, supported single Au on graphdiyne is examined as an efficient catalyst for acetylene hydrochlorination. The adsorption of reactants C2H2 and HCl has a paramount influence on the reaction mechanism. It is indicated that C2H2 adsorption is much stronger than the counterpart of HCl for most of the investigated cases. An Eley–Rideal (E–R) mechanism is first investigated, which is initiated with C2H2 adsorption. In the following steps, the adsorbed C2H2 becomes the site to bind and activate HCl, which leads to formation of the product. It is also revealed that single Au experienced a redox cycle along the reaction pathway. The largest barrier is calculated to be 0.57 eV, corresponding to the product desorption. On the other hand, a novel Langmuir–Hinshelwood (L–H)-like mechanism is also reported, which started with coadsorption of HCl and C2H2. It is noted that the barriers of the LH mechanism are smaller than those of the ER mechanism. Moreover, supported single Au on graphdiyne has much improved performance than the counterpart on pristine graphene and single-walled carbon nanotube support. This work clearly demonstrated the superior performance of supported single Au in acetylene hydrochlorination and the potential of novel support graphdiyne in single-atom catalysis.

Effect of Different Heteroatoms Anchoring a Cu Single-Atom Catalyst on Acetylene Hydrochlorination

“…13 Li et al examined the Au single-atom catalyst supported on graphdiyne through the density functional theory (DFT) and explored a novel L−H mechanism with a smaller barrier than the E−R mechanism, which indicated the potential of the Au singleatom catalyst. 14 The Pt-Cl single-atom active site identified by Peŕez-Rami ́rez et al achieved ∼3-fold higher activity than previously, which qualified this neglected metal for acetylene hydrochlorination. 12 However, though single-atom catalysts can effectively reduce the metal loading and thus reduce the preparation cost, the price and reserves of precious metals are still the main factors limiting their industrialization.…”

“…Single-atom catalysts are currently widely used due to their excellent activity and selectivity in lots of reactions. − At present, different forms of noble metal single-atom catalysts have shown wonderful performance in acetylene hydrochlorination. − For example, the Ru single-atom catalyst supported on activated carbon prepared by our group exhibited excellent performance with 95.4% conversion under harsh reaction conditions and long-term test stability . Li et al examined the Au single-atom catalyst supported on graphdiyne through the density functional theory (DFT) and explored a novel L–H mechanism with a smaller barrier than the E–R mechanism, which indicated the potential of the Au single-atom catalyst . The Pt-Cl single-atom active site identified by Pérez-Ramírez et al achieved ∼3-fold higher activity than previously, which qualified this neglected metal for acetylene hydrochlorination .…”

Stability and Catalytic Performance of Single-Atom Catalysts Supported on Doped and Defective Graphene for CO2Hydrogenation to Formic Acid: A First-Principles Study

“…It has been demonstrated that the interaction between SAC and reactant plays a central role in its catalytic property. ,,,, Therefore, we first study the adsorption of relevant reactants (CO 2 and H 2 ) on three potential SACs (namely, Cu/m-VacG, Ru/m-VacG, and Pd/m-VacG). Figure shows the optimized structures of CO 2 , H 2, and coadsorbed H 2 –CO 2 on these three SACs.…”

Revealing the Tunable Effects of Single Metal Atoms Supported on Nitrogen-Doped Carbon Nanotubes during NO Oxidation from Microkinetic Simulation

“…Therefore, the kind and number of dopants are the decisive parameters to tune the performance of the supported SAC. In fact, our previous studies have demonstrated the validity of this optimization strategy. − The delicate control of dopants could effectively adjust the electronic structure of supported single metal atoms which consequently affected the catalytic performance. Among these dopants, nitrogen stands out as the most studied one due to its similar radius with carbon, which enabled nitrogen to enter the carbon lattice. , It has been widely reported that SACs on nitrogen-doped carbon had remarkable catalytic performance in various catalytic process.…”