Quantum Mechanical Calculations for Biomass Valorization over Metal‐Organic Frameworks (MOFs)

Abstract

Metal-organic framework (MOF) in biomass valorization is a promising technology developed in recent decades. By tailoring both the metal nodes and organic ligands, MOFs exhibit multiple functionalities, which not only extend their applicability in biomass conversion but also increase the complexity of material designs. To address this issue, quantum mechanical simulations have been used to provide mechanistic insights into the catalysis of biomassderived molecules, which could potentially facilitate the development of novel MOF-based materials for biomass valorization. The aim of this review is to survey recent quantum mechanical simulations on biomass reactions occurring in MOF catalysts, with the emphasis on the studies of the catalytic activity of active sites and the effects of organic ligand and porous structures on the kinetics. Moreover, different model systems and computational methods used for MOF simulations are also surveyed and discussed in this review.

Computational Mechanism of Methyl Levulinate Conversion to γ-Valerolactone on UiO-66 Metal Organic Frameworks

“… 21 Despite the many computational contributions on MOF catalysis, 22 , 23 the mechanistic features of how these materials participate in biomass valorization are still scarce. Most of these studies employ finite-size clusters, 24 which ignore the periodicity of the material and cannot account for confinement effects within the pores. To address this gap in knowledge, here we employ periodic density functional theory (DFT) to create a more realistic environment.…”

A Comprehensive Review on Zeolite Chemistry for Catalytic Conversion of Biomass/Waste into Green Fuels

“…Perhaps the periodic or cluster models can be used to conduct these computations. Although systematic DFT simulations for zeolite systems can capture interactions from extended framework structures, they are frequently computationally intensive due to the requirement of large unit cells [ 106 ]. The unphysical border phenomenon may result in inconsistent results when utilising small cluster models, which can significantly cut processing costs.…”

Understanding the Catalytic Activity of Microporous and Mesoporous Zeolites in Cracking by Experiments and Simulations

“…This finding highlights the importance of incorporating a significant part of the zeolite structure into the model. Although the use of a simplified model can reduce computational costs, a small or medium model cannot fully describe the effects of confinement and dispersion effects in porous structures [43], which can significantly influence reaction kinetics in zeolites. Recent developments in quantum mechanics/molecular mechanics simulations offer an efficient way to solve this problem [44].…”

“…These calculations can be performed by either using periodic or cluster models. Periodic models can capture the interactions from the extended framework structures; however, performing periodic DFT simulations for zeolite systems is often computationally demanding due to the need for large unit cells [43]. On the other hand, using small cluster models can significantly reduce computational costs, but the unphysical boundary effect may lead to inaccurate results.…”

“…To address these issues, recent studies have adopted the hybrid quantum mechanics/molecular mechanics (QM/MM) method, in which only a small cluster encompassing the active center is described by quantum mechanics, while the rest of the zeolite framework is described by a classical force field. This hybrid scheme can take into account long-range van der Waals and electrostatic interactions in porous environments without significantly increasing computational costs [43,44]. Nevertheless, low-frequency modes correspond to translational and rotational motions between alkanes and zeolites must be handled properly to derive accurate enthalpies and entropies.…”