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In this article, we present the influence of substituents with different electron-donating (ED) powers on the coordination properties of bis(benzoyloxy)dimethylsilane (BDMS) on the MgCl2 support of Ziegler–Natta (ZN) catalysts through molecular simulation of different adsorption adducts. Thermodynamically, the most favourable adsorption structure was found with the diaminoborane substituent in a bridging mode on the (110) crystalline facet, representing a 37.63% increase at PBEh/TZVP in the adsorption strength of the original silyl ester. Generally, the higher the ED strength of the substituent, the higher the exergonicity of donor coordination. All of the new donors except those containing the nitro and formyl groups are preferably chemisorbed on the (110) surface. While the nitro, formyl, vinyl, and hydroxyl substitutions deteriorated the isotacticity of the polymer, a diaminoborane group was predicted to enhance the isotactic index by 306% relative to the original donor. Particularly, nitrophenyl could improve the isotactic index by 69% while its complexation remained in the thermodynamically controlled regime. Overall, the present DFT study demonstrated how a systematic exploration of substituents over a wide range of ED power can help in the design of new Lewis base donors for ZN catalysis. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) nanomaterials have attracted intense interest since the successful discovery of mechanically exfoliated graphene. Their unique chemical, mechanical, optical, and electrical properties have been exploited in a wide range of applications, including electrical/optoelectrical devices, solar cells, sensors, membranes, and electro/photocatalysis. However, the application of 2D nanomaterials as thermocatalysts is much less common such that a wide range of questions regarding their activity and stability remain. Herein, the application of 2D transition metal dichalcogenides (TMDs), metal phosphorus trichalcogenides (MPTs) and MXenes as thermocatalysts is reviewed. The data indicate that in most cases, reducing the thickness of the catalyst to that of a single or a few layers of atoms, leads to a significant improvement in product selectivity and reaction rate. However, challenges remain, including the low thermal and chemical stability of 2D nanostructures at typical thermocatalytic operating conditions, facile poisoning of the exposed surface, and rapid loss of activity. In addition, the synthesis procedures for 2D nanostructures are complex, making reproducibility and scale-up difficult. This review identifies knowledge gaps to draw attention to these unique materials that have the potential for significant impact as thermocatalysts. [ABSTRACT FROM AUTHOR]