Carbonic Anhydrase-Mimicking Keplerate Cluster Encapsulated Iron Trimesate for Base-Free CO₂ Hydrogenation

Abstract

Producing formic acid (FA) via base-free CO2 hydrogenation suffers from low conversion efficiency because of the difficulty of activating CO2 and the low solubility of CO2 in neutral water. In this paper, we demonstrate a dual catalyst system, incorporating CO2 hydration and Pd/C catalysts to increase the FA yield from base-free CO2 hydrogenation for the first time. As the CO2 hydration catalyst, a carbonic anhydrase-mimicking Keplerate-type Mo132 cluster was used, and its heterogenized catalyst (Mo132@MIL-100­(Fe)) was prepared by encapsulating in a mesoporous iron trimesate (MIL-100­(Fe)) structure. Notably, the addition of a Mo132 cluster greatly increased the FA yields and turnover numbers (TONs) of Pd/C by ∼3.8× through a ligand exchange-derived CO2 hydration process, as confirmed by a NMR study. Mo132@MIL-100­(Fe) was not only separable and recycled along with Pd/C for consecutive reactions without leaching and notable loss of activity, but also showed 2.8× higher TON (1257) compared to the Mo132 cluster (TON = 452) under the same reaction conditions. The present strategy is applicable to various catalytic reactions, especially in aqueous-phase CO2 conversion systems.

Merging Biomass and Co2 Utilization; Process Design and Assessment on Simultaneous Production of Lactic Acid and Formic Acid from Glycerol and Co2

“…previously reported [39,60]. These results show that the proposed 2P2S reaction is a more effective method compared to the 1P1S and 1P2S reactions in terms of KL and KF yield, and the selected Pt/ZrO 2 and Pd/C were proved to be highly active and reusable catalysts for the 2P2S reaction.…”

Pore “Softening” and Emergence of Breathability Effects of New Keplerate Nano‐Containers

“…These internal ligands however are highly labile, and encapsulated anionic guests possessing the appropriate bidentate geometry can exchange with internal ligands, allowing a range of post-synthetic modifications to take place. [15,16] The host properties of the Keplerate combined with tuning of the internal cavity via replacement of acetate with alternative ligands has found diverse uses as a nanoreactor, [17,18] in chiral recognition [19] and as a potential drug delivery mechanism. [20] It has been observed initially that the maximum size of ligand that may be exchanged is dictated by its ability to pass through the open pores, with smaller ligands exchanging faster, and larger ligands being excluded entirely.…”

“…These internal ligands however are highly labile, and encapsulated anionic guests possessing the appropriate bidentate geometry can exchange with internal ligands, allowing a range of post‐synthetic modifications to take place. [ 15 , 16 ] The host properties of the Keplerate combined with tuning of the internal cavity via replacement of acetate with alternative ligands has found diverse uses as a nanoreactor,[ 17 , 18 ] in chiral recognition [19] and as a potential drug delivery mechanism. [20] …”

Enhancing CO2 Hydrogenation Using a Heterogeneous Bimetal NiAl-Deposited Metal–Organic Framework NU-1000: Insights from First-Principles Calculations

“…Metal–organic frameworks (MOFs) have been considered as reliable materials consisting of metal ions or metal-oxo clusters coordinated with organic ligands with their uniform tunable porosity and better-defined local structure, opening new opportunities across several remarkable functions, including the gas sensor, capture, separation, and catalysis. − Taking advantage of their diversities in synthetic tunability, devising permanently porous structures bearing functional catalytically active units that confine and interact well with specific reactants has become a novel strategy for catalyst design. , Recently, MOF-based catalysts have been employed for the low-cost and rational design of catalytic sites and widely used in various reactions, particularly, in the catalytic hydrogenation of CO 2 . − …”