Cyclic Carbonates Research Articles

Zinc Bioinspired Catalytic System for the Valorization of CO2 Into Cyclic Carbonates

AbstractCyclic organic carbonates are defined as key compounds for a sustainable chemical economy. Their synthesis from CO2 under mild conditions is a useful way to valorise this greenhouse gas as carbon source. Even if a wide range of catalysts were described to promote the carbon dioxide cycloaddition into epoxides, only few ones concern enzymatic systems. The zinc–l‐histidine active site of carbonic anhydrase inspired the present work, pointing out that the imidazole moiety of the amino acid ligand has a crucial role. An extensive study was undertaken to establish the structure–activity relationship of imidazole derivatives, zinc salts, and their respective catalytic activity in the CO2 cycloaddition reaction. The effect of aromatic, alkyl, or iodine substituents and their position in N‐heterocycles were highlighted. A synergic effect was noted when combining imidazole compounds with zinc salts. The optimization of reaction conditions emphasised the in situ ZnI2–1‐methylimidazole catalytic system, which is selective toward cyclic styrene carbonates and efficient under solvent‐free mild conditions (50 °C, atmospheric CO2 pressure). Once reusing tests confirmed the catalytic system robustness, the reaction scope was enlarged to several epoxides resulting in 84%–99% yields of their corresponding cyclic carbonates.

Solvent Free Ambient Pressure CO2 Cycloaddition Catalyzed by Cobalt-Impregnated 2D-Nanofibrous COFs.

Covalent organic frameworks (COFs) constitute an evolving class of permanently porous and ordered materials, and they have recently attracted increased interest due to their intriguing morphological features and numerous applications in gas storage, adsorption, and catalysis. However, their low aqueous stabilities and tedious syntheses generally hamper their use in heterogeneous catalysis. Nonetheless, a capable and water-stable heterogeneous catalytic system for coupling CO2/epoxides to generate industrially important cyclic carbonates is still of great interest. Herein, exceedingly water- and thermally stable 2D-cobalt-impregnated hydrazone-linked fibrous COFs are reported as a catalyst for CO2/epoxide coupling reactions at ambient pressure. The functionalized cobalt (Co)-doped COFs demonstrated excellent catalytic activities with the high TONs (80925) and TOFs (6466 h-1), outperforming reported heterogeneous catalysts for CO2/epoxide coupling at ambient pressure. We found that the Co2+ ions within the COF matrix catalyze CO2 cycloaddition through density functional theory calculations. We also confirmed the excellent structural stability and consistent activity of Co-doped COFs up to ten repeating cycles.

Sustainability of Nonisocyanate Polyurethanes (NIPUs)

This work discusses the synthesis and properties of nonisocyanate polyurethanes (NIPUs) as an environmentally friendly alternative to traditional polyurethanes. NIPUs are made without the use of toxic isocyanates, reducing the environmental impact and safety concerns associated with their production. However, their synthesis reactions often require longer time and more energy to be completed. The sustainability of NIPUs is considered from various angles; the main methods for the synthesis of NIPUs, including rearrangement reactions, transurethanization, and ring-opening polymerization of cyclic carbonates with amines, are examined. Another part focuses on renewable sources, such as vegetable oils, terpenes, tannins, lignins, sugars, and others. The synthesis of waterborne and solvent-free NIPUs is also discussed, as it further reduces the environmental impact by minimizing volatile organic compounds (VOCs) and avoiding the use of harmful solvents. The challenges faced by NIPUs, such as lower molecular weight and higher dispersity compared to traditional polyurethanes, which can affect mechanical properties, were also addressed. Improving the performance of NIPUs to make them more competitive compared to conventional polyurethanes remains a key task in future research.

Study of the rheological properties and nautical depth assessment of fine sediments in Iranian ports

Sediments containing more than 10% clay particles by mass can exhibit cohesive properties. Cohesive sediments are commonly found in coastal areas worldwide, including the southern shore of the Caspian Sea and the northern/northwestern beaches of the Persian Gulf. These cohesive sediments can form a layer of soft to extremely soft mud, known as fluid mud, covering the seabed. The study examined the properties of natural mud samples collected from different depths and locations within three Iranian ports: Anzali Port (Caspian Sea), and Khorramshahr and Bushehr Ports (Persian Gulf). The laboratory analyses included determining the sediment grain-size distribution, density, carbonate content, organic matter content, and rheological properties at different water content ratios. Disregarding the impact of variations in organic matter and carbonate contents in the samples, water content ratio was the main factor affecting the rheological properties of sediments.

Reductive Transformation of CO2 to Organic Compounds.

Carbon dioxide is a major greenhouse gas and a safe, abundant, easily accessible, and renewable C1 resource that can be chemically converted into high value-added chemicals, fuels and materials. The preparation of urea, organic carbonates, salicylic acid, etc. from CO2 through non-reduction conversion has been used in industrial production, while CO2 reduction transformation has become a research hotspot in recent years due to its involvement in energy storage and product diversification. Designing suitable catalysts to achieve efficient and selective conversion of CO2 is crucial due to its thermodynamic stability and kinetic inertness. From this perspective, the redistribution of charges within CO2 molecules through the interaction of Lewis acid/base or metal complexes with CO2, or the forced transfer of electrons to CO2 through photo- or electrocatalysis, is a commonly used effective way to activate CO2. Based on understanding of the activation/reaction mechanism on a molecular level, we have developed metal complexes, metal salts, inorganic/organic salts, ionic liquids, as well as nitrogen rich and porous materials as efficient catalysts for CO2 reductive conversions. The goal of this personal account is to summarize the catalytic processes of CO2 reductive conversion that have been developed in the past 7 years: 1) For the reductive functionalization of CO2, the major challenge lies in accurately adjusting reaction parameters (such as pressure) to achieve high catalytic efficiency and the product selectivity; 2) For photocatalytic or electrocatalytic reduction of CO2, how to suppress competitive hydrogen evolution reactions and improve catalyst stability are key points that requires continuous attention.

Photo-induced hydroxypentafluorosulfanylation of alkenes with SF5Cl and oxygen gas and their further derivatization

Fluorinated or fluoroalkylated alcohols are common structural motifs in biologically active molecules, natural products, and pharmaceuticals. However, pentafluorosulfanyl (SF5) alcohols, a unique class of SF5 compounds that serve as synthetically valuable building blocks, are difficult to prepare with current methodologies. In this article, we present a single-step, metal-free, and photo-induced hydroxypentafluorosulfanylation of styrenes or α,β-unsaturated esters/amide, producing a series of structurally diverse pentafluorosulfanyl alcohols with up to 89% yields. This reaction is mild and operationally simple, using molecular oxygen as the hydroxy source. The protocol is suitable for a wide range of alkenes, including natural products and drug molecule derivatives. The formed SF5 alcohol units can be readily converted into diverse functionalized SF5 compounds, such as α-SF5 ketones, SF5 diols, and SF5 cyclic carbonates. The potential applications of these SF5 compounds in pharmaceutical and material sciences are vast, making this research a step forward in the field.

Bulky Phosphazenium Salt Controlling Chemoselective Terpolymerization of Epoxide, Anhydride and CO2: From Well‐Defined Block to Truly Random Copolymers

AbstractCopolymers with precise compositions and controlled sequences are great appealing for high‐performance polymeric materials, but their synthesis is very challenging. In this study, tetrakis[tris(dimethylamino)phosphoranylidenamino] phosphonium chloride (P5Cl) and triethylboron (TEB) were chosen as the binary catalyst to synthesize both well‐defined block and truly random poly(ester–carbonate) copolymers via the one‐pot/one‐step terpolymerization of epoxide/anhydride/CO2 under metal‐free conditions. The bulky nature of phosphazenium cation not only led to loose cation–anion pairs and enhanced the reactivity, but also provided the chain‐end an appropriate protection and improved the controllability. In particular, P5Cl/TEB with a molar ratio of 1/0.5 showed an extraordinary chemoselectivity for ring‐opening alternating copolymerization (ROAC) of cyclohexene oxide (CHO) and phthalic anhydride (PA) first and then ROAC of CHO/CO2. Thus, well‐defined block polyester–polycarbonate copolymers were synthesized by CHO/PA/CO2 terpolymerization. The chemoselectivity was easily tuned and the ROAC of CHO/PA and ROAC of CHO/CO2 occurred simultaneously with P5Cl/TEB=1/2, producing truly random poly(ester–carbonate) copolymers from CHO/PA/CO2. In addition, this P5Cl/TEB catalyst and the strategy to regulate its chemoselectivity are versatile for various anhydrides, epoxides and initiators. Thus, poly(ester–carbonate) copolymers with varying sequences, compositions, and topologies are successfully synthesized, making it possible to compare their properties and to expand their applications.

Systematic study on the hydrogen abstraction reactions from oxygenated compounds by H and HO2

AbstractTo extend the rule‐based approach for hydrogen abstraction reactions from oxygenated compounds, a systematic investigation was performed to examine the reactivity of gas‐phase hydrogen abstraction reactions from alkyl groups (methyl and ethyl groups) bound to oxygen atoms in five types of oxygenated compounds (alcohols, ethers, formate esters, acetate esters, and carbonate esters) by H atoms and HO2 radicals comprehensively considering rotational conformers. Quantum chemical calculations were conducted at the CBS‐QB3 level for stationary points. Rate constants were determined employing conventional transition state theory (TST). For hydrogen abstraction reactions by H, the rotational conformer distribution partition function was employed to approximate partition functions, owing to the similarity in vibrational energy‐level structures among conformers. In hydrogen abstraction reactions by HO2, the vibrational structures of transition‐state (TS) conformers varied significantly due to the hydrogen bonding, leading to an inappropriate evaluation of rate constants when using the lowest‐energy conformer as a representative. Therefore, the rate constants were calculated by the multi‐structural TST. It was revealed that the differences in functional groups containing O atoms mainly affect the bond dissociation energies of the C–H bonds and the activation energies of hydrogen abstraction reactions only when the C atoms are adjacent to the O atoms. Additionally, it was found that hydrogen bonds formed in the TSs show minor effect on rate parameters for the overall rate constants, apart from the reduction of the pre‐exponential factors for the H‐abstraction reactions from the methylene position of ethyl groups. The comparison with the rate constants from previous studies showed reasonable results, indicating that the rate constants in this study, which thoroughly consider rotational conformers, can be the current best estimates.

One-pot synthesis of copper phthalocyanine polymer: An efficient CO2 fixation catalyst

The chemical transformation of CO2 into high-value-added products is not only favourable to environmental preservation, but also promising for economy. Developing novel and practical catalysts play a critical role in facilitating conversion of CO2 and the synthesis of high value-added chemicals. Herein, we present the fabrication of biphenyl-typed copper phthalocyanine polymer (BPh-CuPc) from 4,4’-bis(3,4-dicyanophenoxy)biphenyl via a one-pot synthesis procedure, and application of it as a promising catalyst for CO2 conversion into cyclocarbonate. FTIR, XPS, UV–vis, TGA and SEM measurements confirm the successful fabrication of BPh-CuPc. Attributing to the existence of copper ions which can act as a Lewis acid to activate epoxide, and phthalocyanine rings that is positive for CO2 absorption, within the chemical framework of BPh-CuPc, it exhibits excellent catalytic activity for CO2 conversion into cyclic carbonates under mild conditions when combined with tetrabutylammonium iodide (TBAI). As a result, a 98 % yield and 99 % selectivity are obtained for the BPh-CuPc/TBAI system in CO2/propylene oxide conversion under condition of 90 °C, 8 h and 2.0 MPa. The obtained high yield and selectivity, as well as remarkable stability and versatility, validate the promising application of BPh-CuPc as a CO2 conversion catalyst. SynopsisAttributing to the existence of copper ions and phthalocyanine rings within the chemical framework, BPh-CuPc exhibits excellent catalytic activity for CO2 conversion into cyclic carbonates under mild conditions.

Synergistic effects of hydroxyl and tertiary amine in the catalytic carbonatization of epoxides with CO2 at atmospheric pressure

Fixation of carbon dioxide is a key issue for the sustainable synthesis of chemical compounds. A catalyst system for the preparation of cyclic carbonates by the fixation of carbon dioxide (CO2) onto epoxides is presented. This system is designed for easy application due to the availability of the compounds on an industrial scale as well as moderate reaction conditions. Notably, it avoids the use of metal-halogen catalysts and instead employs a tertiary amine as the catalytic center, in conjunction with an alcohol acting as a hydrogen bond donor (HBD). The kinetics of the cycloaddition reaction between epoxides and CO2 were thoroughly investigated using IR spectroscopy. Remarkably, optimization of the amino-to-alcohol group ratio and the amine structure was carried out to enhance the overall performance of the catalyst system showing a synergistic effect between the tertiary amine and the hydroxyl. Most notably, this entire process is conducted without the use of solvents and operates at ambient pressure, underscoring its significant ecological advantages.

CO2 Fixation via epoxide cycloaddition with a highly active and stable MOF-808/GO composite catalyst

The CO2 cycloaddition reaction effectively mitigates the greenhouse effect while producing high-value cyclic carbonates. Metal-organic frameworks (MOFs) have shown promise for CO2 cycloaddition with epoxides; however, the aggregation of MOFs due to high surface energy hinders mass transfer and catalytic performance. By pre-coordinating graphene oxide (GO) to regulate the dispersion of MOF-808, the resulting MOF-808/GO-100 composite catalyst exhibits twice the activity of pristine MOF-808, achieving 92.6% conversion of epichlorohydrin (ECH) with 98.2% selectivity to ECH carbonate without adding any co-catalysts. The incorporation of GO introduces numerous hydroxyl groups on the catalyst surface, serving as hydrogen bonding donors. The oxygen-containing groups on GO can compete with ligands for Zr coordination, generating defective Zr sites. The synergistic effect between defective Zr sites and hydrogen bonding donors collectively promotes epoxide opening. Notably, GO correspondingly enhances the dispersion of MOF-808 and induces mesopore formation through its stacking effect at the interface with MOF-808. Across various epoxide cycloaddition reactions, MOF-808/GO-100 consistently demonstrated optimal performance and maintained high stability over multiple reaction cycles.

Continuous CO2 cycloaddition to cyclic carbonate in a membrane dispersion enhanced fixed-bed reactor

CO2 cycloaddition is an effective approach to achieve high-value chemical products and mitigate greenhouse gas emissions. However, high-efficiency and continuous CO2 cycloaddition keeps a significant challenge. Herein, continuous liquid-phase CO2 cycloaddition to cyclic carbonate is successfully realized for the first time in a membrane dispersion enhanced fixed-bed reactor. The reactor system can be operated steadily for 100 h with a productivity of 15.9 gcyclic carbonate·h−1·gcat.−1, more than ten times that of the traditional fixed-bed reactor.

Two Sustainable Pathways of MOF-Catalyzed Room Temperature Chemical Fixation of CO2 inside Alkynes under Atmospheric Pressure.

The rising atmospheric CO2 levels necessitate the development of effective materials for its mitigation. Utilization of adsorbent materials for the reversible physisorption of CO2 has a significantly less impact. Recognizing this need, herein, we present a nitrogen-rich, aqua-stable, Ag(0)-nanoparticle-doped metal-organic framework (MOF) designed for the irreversible chemical conversion of CO2 into valuable fine chemicals. We demonstrate two sustainable pathways for CO2 fixation, utilizing the catalyst, 1'@Ag NPs. The designed catalyst facilitates the cyclization of propargylic amines and alcohols under ambient temperature and pressure conditions. Remarkably, this is the first MOF-based catalyst that allows for quantitative conversion of propargylic amines into 2-oxazolidinones at room temperature with atmospheric CO2 pressure. The process successfully transforms various propargylic amines and alcohols into 2-oxazolidinones and α-alkylidene cyclic carbonates under the CO2 atmosphere. Additionally, the catalyst shows excellent recyclability, maintaining its activity and structural integrity across multiple reuse cycles. Control experiments revealed that the catalytic efficiency of 1'@Ag NPs is attributed to the highly exposed alkynophilic Ag(0) sites on its pore walls. Computational studies further elucidate the mechanistic pathway for CO2 fixation. This work highlights the potential of 1'@Ag NPs to enhance environmental sustainability by converting CO2 into valuable bioactive chemicals under mild conditions.

Transforming Element Sulfur to High Performance Closed‐Loop Recyclable Polymer via Proton Transfer Enabled Anionic Hybrid Copolymerization

AbstractThe utilization of sulfur has been a global issue. Copolymerization of element sulfur (S8) with other monomers is a promising route to convert it to useful materials but is limited by the comonomers. Here, we report anionic hybrid copolymerization of S8 with acrylate and epoxide at room temperature, where S8 does not copolymerize with epoxide in the absence of acrylate. Yet, the proton transfer from the methyne in acrylate to the oxygen anion enables the ring‐opening of the cyclic comonomer and hence the copolymerization. The cyclic comonomers can be expanded to lactone and cyclic carbonate. Specifically, the copolymer of S8 with bisphenl A diglycidyl ether and diacrylate displays mechanical properties comparable to those of most common plastics, namely, it has ultimate tensile strength as high as 60.8 MPa and Young's modulus up to 680 MPa. It also exhibits high UV resistance and good transparency. Particularly, it has excellent UV‐induced self‐healing, reprocessability and closed‐loop recyclability due to the abundant dynamic S−S bonds and ester groups. This study provides an efficient strategy to turn element sulfur into closed‐loop recyclable polymer with high mechanical and optical performances.

Capture and in-situ conversion of low-concentration CO2 over robust poly(ionic liquid)@porous carbon nanocomposites under green, co-catalyst- and solvent-free conditions

The development of advanced materials with dual functionalities for the capture of low-concentration CO2 and its in-situ conversion into value-added chemicals under mild and green conditions holds significant practical importance. In this study, we present a facile pyrolysis of fluid precursors followed by an in-situ polymerization strategy for preparing poly(ionic liquid)@porous carbon nanocomposites (PIL-Brx@Zn-CTM), which possess multiple active sites including Lewis acidic Zn2+, Lewis basic N, and nucleophilic Br– groups. Subsequently, we investigate their potential application in the efficient capture and conversion of low-concentration CO2 into cyclic carbonates. The influence of PIL-Brx@Zn-CTM structures and technological conditions on the cycloaddition reaction between low-concentration CO2 (15 % CO2 and 85 % N2) and epichlorohydrin was examined. The PIL-Br1.0@Zn-CTM nanocomposite was determined to be the most suitable catalyst, resulting in a 94 % yield of chloropropene carbonate with 99 % selectivity under mild, co-catalyst-, and solvent-free conditions. Furthermore, the reusability of PIL-Br1.0@Zn-CTM and its substrate scope were investigated. The PIL-Br1.0@Zn-CTM exhibited sustained high activity without a significant decrease after seven cycles of reuse, and it also demonstrated excellent catalytic activity for cycloaddition reactions involving low-concentration CO2 with various substituted epoxides. Finally, a mechanism for the cycloaddition reaction catalyzed by the PIL-Brx@Zn-CTM nanocomposite was proposed.

Destruction of Per- and Polyfluoroalkyl Substances in Reverse Osmosis Concentrate Using UV-Advanced Reduction Processes.

UV-advanced reduction processes (UV-ARP), characterized by the strongly reducing aqueous electron (eaq -), have been shown to degrade perfluoroalkyl and polyfluoroalkyl substances (PFAS). Due to the high cost of PFAS destruction technologies, concentrated waste streams derived from physical treatment processes, such as ion exchange or membrane concentrates, are promising targets for implementation of these technologies. However, there are limited studies on the application of UV-ARP for PFAS destruction in concentrated waste streams. This study evaluates the effectiveness of the UV/sulfite ARP in reverse osmosis concentrate (ROC) containing high concentrations of dissolved organic carbon (DOC), nitrate, and carbonate species, spiked with mg/L concentrations of perfluorooctanesulfonic acid, perfluorobutanesulfonic acid, perfluorooctanoic acid, and perfluorobutanoic acid. We demonstrate that hardness removal and preoxidation of ROC with UV/persulfate enables >90% PFAS defluorination within 24 h of subsequent UV/sulfite treatment, a 3-fold enhancement in defluorination % compared to UV/sulfite treatment without preoxidation. This enhancement is shown to result from abatement of the light shielding and eaq - scavenging capacity of DOC during UV/persulfate oxidation. Collectively, these results demonstrate that appropriate pretreatment steps increase the effectiveness of PFAS destruction using UV-ARP, supporting the application of UV-ARP for PFAS destruction in ROC and other concentrated waste streams.

Synthesis and catalytic application to form cyclic carbonates of novel Pd(II) Cu(II), and Fe(II) benzoate-based Schiff base metal complexes

This work describes the synthesis and characterisation of six novel Schiff base complexes, Cu(II), Pd(II), and Fe(II), which, under the right circumstances, function as very efficient catalysts for the production of cyclic carbonates from CO2 and epoxides. FT-IR spectroscopy, elemental analysis, UV–Vis spectroscopy, molar conductivity, melting point, and magnetic susceptibility measurements are among the spectroscopic methods used to characterize newly synthesized complexes. The molar conductivity values, ranging from 2.58 to 4.03 µS/cm, suggest that the complexes exhibit no molar conductivity. Co-catalysts, such as 4-(dimethylamino)pyridine, pyridine, triethylamine, and triphenyl phosphine, were used in these processes, both with and without one. 4-(Dimethylamino)pyridine was used as the co-catalyst in the catalytic studies. Additionally, a number of variables that affect the cycloaddition process were examined, including the temperature, CO2 pressure, reaction time, and co-catalyst. All novel catalysts exhibited exceptional catalytic activity and selectivity in the catalytic assays. Regarding the coupling of CO2 and epichlorohydrin as epoxides, the L2-Cu catalyst outperformed other catalysts in terms of catalytic activity (90.7%) and selectivity (98.9%).

Learning Strategies from Nature's Blueprint to Cyclic Carbonate Synthesis.

Nature is a remarkable source of inspiration for developing sustainable and eco-friendly synthetic procedures. In recent years, the synthesis of cyclic carbonates has garnered significant attention due to their versatile applications in various fields, including materials science, pharmaceuticals, and green chemistry. Drawing inspiration from nature, researchers have explored innovative synthetic routes that mimic biological processes to produce cyclic carbonates efficiently and sustainably. This article reviews nature-inspired synthetic procedures for cyclic carbonate formation, highlighting the key strategies and principles employed. Through biomimicry, researchers aim to harness the efficiency and selectivity observed in biological systems to develop greener and more sustainable methods for cyclic carbonate synthesis. Integrating bio-inspired strategies offers opportunities for improving synthetic efficiency and contributes to reducing the environmental impact associated with traditional chemical processes. This review underscores the potential of nature-inspired approaches in advancing the field of cyclic carbonate synthesis toward more sustainable and environmentally benign practices, focusing on recent literature.

Heterogeneous Catalytic Materials for Carbon dioxide Transformation: Efficient Carboxylation Cyclization to Cyclic Carbonates and Oxazolidinones

The exacerbation of environmental issues is increasingly attributed to the anthropogenic emissions of carbon dioxide (CO2) . CO2 is a cost‐effective and readily available C1 source. The conversion of CO2 into value‐added organic chemicals, such as cyclic carbonate and 2‐oxazolidinone, through carboxylation cyclization reactions shows promise in reducing carbon emissions and combating climate change. The use of catalysts can facilitate this process, with heterogeneous catalysts emerging as favorable due to their advantages of easy recovery and structural stability. This paper provides a comprehensive review of heterogeneous catalysts that have been utilized for the carboxylation cyclization of CO2 to afford cyclic carbonates and oxazolidinones in recent years. The catalysts include metal organic frameworks, covalent organic frameworks, super‐crosslinked polymers, conjugated microporous polymers, porous ionic organic polymers, and composite materials. We give a detailed synthesis route for each type of catalysts. Furthermore, the characteristics of the catalysts, such as BET specific surface area, CO2 adsorption capacity, and catalytic performance, is summarized and analyzed to offer insights for improving heterogeneous catalysts for CO2 conversion via carboxylation cyclization reactions in future research.

Comparative Study of High Voltage Spinel∥Lithium Titanate Lithium‐ion Batteries in Ethylene Carbonate Free Electrolytes

AbstractA persistent obstacle towards the realization of high voltage cathodes is electrolyte instability where oxidation and transition metal dissolution manifest in rapid capacity failure with both issues connected to the presence of ethylene carbonate in the electrolyte. Here, alternative electrolyte co‐solvents are investigated and compared, where the cyclic carbonate is replaced with sulfones ethyl methyl sulfone (EMS) and tetra methylene sulfone (TMS) and fluoroethylene carbonate (FEC). The best full cell performance was observed for cells cycled in a FEC/EMC (3/7) and FEC/EMC (1/1) electrolytes which exhibited 84–85 % capacity retention after 500 cycles. TMS/EMC (3/7), was determined to be the best performing sulfone electrolyte and maintained 71 % capacity after 500 cycles. Post‐mortem XPS analysis indicated different film forming mechanisms for the respective co‐solvent. A thicker cathode electrolyte interphase (CEI) on the LNMO was observed for the FEC containing electrolytes (relative to when TMS was used as the co‐solvent) indicating more effective passivation of the reactive cathode surface which correlated well with the enhanced cycling stability observed. For LTO, more evidence of transition metal migration and a thicker solid electrolyte interphase (SEI) layer was observed for the sulfone electrolyte suggesting more parasitic anode‐electrolyte interactions and an inability to mitigate Mn2+/Ni2+ crosstalk.