Ion Transport Channels Research Articles

Palygorskite-Derived Ternary Fluoride with 2D Ion Transport Channels for Ampere Hour-Scale Li-S Pouch Cell with High Energy Density.

Although various excellent electrocatalysts/adsorbents have made notable progress as sulfur cathode hosts on the lithium-sulfur (Li-S) coin-cell level, high energy density (WG ) of the practical Li-S pouch cells is still limited by inefficient Li-ion transport in the thick sulfur cathode under low electrolyte/sulfur (E/S) and negative/positive (N/P) ratios, which aggravates the shuttle effect and sluggish redox kinetics. Here a new ternary fluoride MgAlF5 ·2H2 O with ultrafast ion conduction-strong polysulfides capture integration is developed. MgAlF5 ·2H2 O has an inverse Weberite-type crystal framework, in which the corner-sharing [AlF6 ]-[MgF4 (H2 O)2 ] octahedra units extend to form two-dimensional Li-ion transport channels along the [100] and [010] directions, respectively. Applied as the cathode sulfur host, the MgAlF5 ·2H2 O lithiated by LiTFSI (lithium salt in Li-S electrolyte) acts as a fast ionic conductor to ensure efficient Li-ion transport to accelerate the redox kinetics under high S loadings and low E/S and N/P. Meanwhile, the strong polar MgAlF5 ·2H2 O captures polysulfides by chemisorption to suppress the shuttle effect. Therefore, a 1.97Ah-level Li-S pouch cell achieves a high WG of 386Whkg-1 . This work develops a new-type ionic conductor, and provides unique insights and new hosts for designing practical Li-S pouch cells.

Porous powder synthesis of (FeCoCrMnNi)3O4 high entropy ceramic and its supercapacitor applications

High entropy materials are becoming more and more popular in energy storage field of supercapacitors because of their unique structure and modulated functional characteristics, but their low conductivity and instability of electrode structure limit their further electrochemical performance. In this paper, we use polyethylene glycol (PEG) with different molecular weights to modify the surface morphology of the high entropy oxides (FeCoCrMnNi)3O4 in an attempt to improve their supercapacitors performance. The PEG was used as a pore-making agent to prepare porous high entropy oxides powder with a large specific surface area of 92.7559 m2 g−1, providing more active sites and ion transport channels. A high specific capacitance of 204 F g−1 at 0.5 A g−1 and good cycle performance of 60.4 % capacitance retention after 10,000 cycles were obtained. Besides, an asymmetric device with improved energy density of 53 W h kg−1 and the power density of 400.8 W kg−1 were reached via the designed microstructure of the high entropy oxide electrode.

Tailoring hierarchical porous core–shell SnO2@Cu upon Cu–Sn alloys through oxygen binding energy difference for high energy density lithium-ion storage

Rational design and construction of self-supporting anodes with high energy density is an essential part of research in the field of lithium-ion batteries. Tin oxide (SnO2) is restricted in application as a prospective high energy density anode due to inherent low conductivity and huge volume expansion of the charge/discharge process. A new strategy that combines high energy ball milling and nonsolvent induced phase separation (NIPS) method was employed to synthesize self-supporting electrodes in which porous SnO2 was encapsulated in a three-dimensional hierarchical porous copper (Cu) shell structure (3DHPSnO2@Cu). This unique structure was constructed due to the different binding energy of the alloy with oxygen, which are −0.91 eV for Cu41Sn11 and −1.17 eV for Cu5.6Sn according to the density functional theory calculation. 3DHPSnO2@Cu electrodes exhibited excellent discharge capacity with an initial reversible capacity of 4.35 mAh cm−2 and a reversible capacity of 3.13 mAh cm−2 after 300 cycles at a current density of 1.4 mA cm−2. It is attributed that the porous Cu shell encapsulated with porous SnO2 provides buffer volume. Among them, the SnO2-Cu-SnO2 interface increases the electrical conductivity and the porous structure provides ion transport channels. This strategy opens a new pathway in the development of self-supporting electrode materials with high energy density.

Continuous Ultrathin Zwitterionic Covalent Organic Framework Membrane Via Surface-Initiated Polymerization Toward Superior Water Retention.

Efficient construction of proton transport channels in proton exchange membranes maintaining conductivity under varied humidity is critical for the development of fuel cells. Covalent organic frameworks (COFs) hold great potential in providing precise and fast ion transport channels. However, the preparation of continuous free-standing COF membranes retaining their inherent structural advantages to realize excellent proton conduction performance is a major challenge. Herein, a zwitterionic COF material bearing positive ammonium ions and negative sulphonic acid ions is developed. Free-standing COF membrane with adjustable thickness is constructed via surface-initiated polymerization of COF monomers. The porosity, continuity, and stability of the membranes are demonstrated via the transmission electron microscopy (TEM), atomic force microscopy (AFM), and scanning electron microscopy (SEM) characterization. The rigidity of the COF structure avoids swelling in aqueous solution, which improves the chemical stability of the proton exchange membranes and improves the performance stability. In the higher humidity range (50-90%), the prepared zwitterionic COF membrane exhibits superior capability in retaining the conductivity compared to COF membrane merely bearing sulphonic acid group. The established strategy shows the potential for the application of zwitterionic COF in the proton exchange membrane fuel cells.

Multiscale carbon - Based ion channel fiber membrane for efficient osmotic energy capture

The green energy generated by salinity gradient at the river-sea junction can be captured by Reverse Electrodialysis (RED) technology. The ion migration in the energy conversion process occurs in the narrow ion channel inside the permeable membrane of the core component. In practical applications, membrane used for osmotic energy conversion needs to meet the necessary conditions such as effective nano-channels, sufficient surface charges, large-scale preparation and stable energy output. It is challenging to achieve all of these requirement at the same time and calls for an exquisite design of the permeable membrane. Herein, we demonstrate an ion channel membrane regulated by a carbon-based membrane with hierarchical channels for efficient osmotic energy conversion. Porous carbon (PC) nanosheets with high porosity and high modulus are filled into carbon nanofibers (CNFS)/graphene oxide (GO) composite membrane, increasing ion transport channels and providing additional space charge to improve ion selectivity. The power output from PC@GO/CNFs membranes modified with nano-porous carbon reaches 4.3 W·m−2. In addition, the ion-selective membrane obtained by this strategy has the advantages of simple process, adjustable area and good stability. This simple strategy is one of the feasible paths for infiltration to be collected effectively. Ion-selective membrane is the key component for osmotic energy conversion.

Solid-State Electrolytes and Electrode/Electrolyte Interfaces in Rechargeable Batteries.

Solid-state batteries (SSBs) are considered to be one of the most promising candidates for next-generation energy storage systems due to the high safety, high energy density and wide operating temperature range of solid-state electrolytes (SSEs) they use. Unfortunately, the practical application of SSEs has rarely been successful, which is largely attributed to the low chemical stability and ionic conductivity, ineluctable solid-solid interface issues including limited ion transport channels, high energy barriers, and poor interface contact. A comprehensive understanding of ion transport mechanisms of various SSEs, interactions between fillers and polymer matrixes and the role of the interface in SSBs are indispensable for rational design and performance optimization of novel electrolytes. The categories, research advances and ion transport mechanism of inorganic glass/ceramic electrolytes, polymer-based electrolytes and corresponding composite electrolytes are detailly summarized and discussed. Moreover, interface contact and compatibility between electrolyte and cathode/anode are also briefly discussed. Furthermore, the electrochemical characterization methods of SSEs used in different types of SSBs are also introduced. On this basis, the principles and prospects of novel SSEs and interface design are curtly proposed according to the development requirements of SSBs. Moreover, the advanced characterizations for real-time monitoring of interface changes are also brought forward to promote the development of SSBs.

Breaking Mass Transport Limitations by Iodized Polyacrylonitrile Anodes for Extremely Fast‐Charging Lithium‐Ion Batteries

AbstractThe fast‐charging capability of rechargeable batteries is greatly limited by the sluggish ion transport kinetics in anode materials. Here we develop an iodized polyacrylonitrile (I‐PAN) anode that can boost the bulk/interphase lithium (Li)‐ion diffusion kinetics and accelerate Li‐ion desolvation process to realize high‐performance fast‐charging Li‐ion batteries. The iodine immobilized in I‐PAN framework expands ion transport channels, compresses the electric double layer, and changes the inner Helmholtz plane to form LiF/LiI‐rich solid electrolyte interphase layer. The dissolved iodine ions in the electrolyte self‐induced by the interfacial nucleophilic substitution of PF6− not only promote the Li‐ion desolvation process, but also reuse the plated/dead Li formed on the anode under fast‐charging conditions. Consequently, the I‐PAN anode exhibits a high capacity of 228.5 mAh g−1 (39 % of capacity at 0.5 A g−1 delivered in 18 seconds) and negligible capacity decay for 10000 cycles at 20 A g−1. The I‐PAN||LiNi0.8Co0.1Mn0.1O2 full cell shows excellent fast‐charging performance with attractive capacities and negligible capacity decay for 1000 cycles at extremely high rates of 5 C and 10 C (1 C=180 mA g−1). We also demonstrate high‐performance fast‐charging sodium‐ion batteries using I‐PAN anodes.

Breaking Mass Transport Limitations by Iodized Polyacrylonitrile Anodes for Extremely Fast-Charging Lithium-Ion Batteries.

The fast-charging capability of rechargeable batteries is greatly limited by the sluggish ion transport kinetics in anode materials. Here we develop an iodized polyacrylonitrile (I-PAN) anode that can boost the bulk/interphase lithium (Li)-ion diffusion kinetics and accelerate Li-ion desolvation process to realize high-performance fast-charging Li-ion batteries. The iodine immobilized in I-PAN framework expands ion transport channels, compresses the electric double layer, and changes the inner Helmholtz plane to form LiF/LiI-rich solid electrolyte interphase layer. The dissolved iodine ions in the electrolyte self-induced by the interfacial nucleophilic substitution of PF6 - not only promote the Li-ion desolvation process, but also reuse the plated/dead Li formed on the anode under fast-charging conditions. Consequently, the I-PAN anode exhibits a high capacity of 228.5 mAh g-1 (39 % of capacity at 0.5 A g-1 delivered in 18 seconds) and negligible capacity decay for 10000 cycles at 20 A g-1 . The I-PAN||LiNi0.8 Co0.1 Mn0.1 O2 full cell shows excellent fast-charging performance with attractive capacities and negligible capacity decay for 1000 cycles at extremely high rates of 5 C and 10 C (1 C=180 mA g-1 ). We also demonstrate high-performance fast-charging sodium-ion batteries using I-PAN anodes.

The influence of polymer powder on the ion transportation and antierosion mechanism of cement mortar: From experiments to molecular dynamics simulation

As the main product of hydration reaction of common Portland cement, calcium silicate hydrate (C-S-H) gel is a porous gel system containing capillary and gel pores. These channels act as transport channels for water molecules and ions in the cement system. The diffusion of water molecules and ions through C-S-H gel channels has significant effects on the strength, shrinkage, creep, chemical and physical reactions of the cement system. Polymer can modify cement-based materials and improve their ionic permeability resistance. In this study, emulsified asphalt powder (EAP) and vinyl acetate ethylene copolymer (VAE) redispersible polymer powder was added into the Portland cement mortar as admixtures, respectively. The influence of redispersible polymer powder on the transportation and erosion mechanism of ions in cement mortar was investigated by analyzing the pore structure, compressive strength ratio, chloride ion permeability depth and micromorphological of cement mortar. The adsorption and diffusion behaviors of ions with different concentrations and water molecules were explored by molecular dynamics simulation, and the physiochemical reactions between ions and hydration products during the transport process in cement-based materials were comprehended.

Ion transport regulation of polyimide separator for safe and durable Li-metal battery

Li-metal battery (LMB) gains enormous attentions because of its high energy and power density. However, the cycling stability of LMB is seriously harmed by the increase of internal temperature and Li-dendrite growth. The development of high-safety thermotolerant separators is urgently desired that can provide advantageous channels for rapid ion transport and simultaneously enable homogeneous Li+ fluxes to inhibit dendrite growth. With superior thermal and electrochemical stability, polyimide-based separator is a good alternative to commercial polyolefin-based separators, but prior design of either nanopores or micropores in polyimide-based separator usually met a dilemma. In this work, we report a polyimide sandwiched separator (denoted as s-PIF) with polyimide fiber (PIF) membrane coated by polyimide aerogels. Significant advancements in terms of mechanical property, electrolyte adsorption/retention and ion conductivity can be achieved for the s-PIF separator, compared with PIF separator. Moreover, the s-PIF separator can render a dendrite-free process of Li plating/stripping for 1400 h. Consequently, the LMB with s-PIF separator shows a remarkable stability with 80 % of its capacity retention after 3000 cycles at 10C.

Amorphous Modulation of Atomic Nb-O/N Clusters with Asymmetric Coordination in Carbon Shells for Advanced Sodium-Ion Hybrid Capacitors.

Anode materials with excellent properties have become the key to develop sodium-ion hybrid capacitors (SIHCs) that combine the advantages of both batteries and capacitors. Amorphous modulation is an effective strategy to realize high energy/power density in SIHCs. Herein, atomically amorphous Nb-O/N clusters with asymmetric coordination are in situ created in N-doped hollow carbon shells (Nb-O/N@C). The amorphous clusters with asymmetric Nb-O3/N1 configurations have abundant charge density and low diffusion energy barriers, which effectively modulate the charge transport paths and improve the reaction kinetics. The clusters are also enriched with unsaturated vacancy defects and isotropic ion-transport channels, and their atomic disordering exhibits high structural stress buffering, which are strong impetuses for realizing bulk-phase-indifferent ion storage and enhancing the storage properties of the composite. Based on these features, Nb-O/N@C achieves notably improved sodium-ion storage properties (reversible capacity of 240.1 mAh g-1 at 10.0 A g-1 after 8000 cycles), and has great potential for SIHCs (230Wh Kg-1 at 4001.5W Kg-1). This study sheds new light on developing high-performance electrodes for sodium-ion batteries and SIHCs by designing amorphous clusters and asymmetric coordination.

Homogenous conduction: Stable multifunctional gel polymer electrolyte for lithium-sulfur batteries

The low sulfur utilization rate and polysulfide shuttle are the main reasons that hinder the practical process of lithium-sulfur batteries. Here, an effective structural engineering strategy of multifunctional gel polymer electrolyte (GPE) by electrospinning was proposed. The HCNF@HPAN-GPE for lithium-sulfur batteries contained halloysite-base carbon nanofibers (HCNF) offered abundant active sites as sulfur fixation layer and halloysite-base polyacrylonitrile (HPAN) provided ion transport channel as ion transport layer. Both layers were abundant in the halloysite nanotubes as “transduction segment” and established the synergistic interface conduction. The HCNF@HPAN-GPE exhibited an ionic conductivity of 8.01 × 10−3 S cm−1. Therefore, the HCNF@HPAN-GPE displayed excellent interface compatibility and stabilized lithium deposition/ stripping over 800 h. Meanwhile, it demonstrated an initial discharge specific capacity of 1461.2 mA h g−1 at 0.1 C and an ultra-low-capacity attenuation of 0.056 % per cycle of 800 cycles at 1 C. In sum, this study may provide a novel strategy for the effective design of GPE toward the high performance lithium-sulfur batteries.

Facet dependent ion channel of iron phosphate for electrochemical lithium extraction

Lithium resources can be extracted from liquid by electrochemical intercalation processes. However, the response of material structure to ion transport channels in aqueous environments is not fully understood, which limits the effective design of materials. In this study, we present LiFePO4 samples with exposed (100) and (010) crystal facets (named LFP (100) and LFP (010)) as a model host to explore ion transport behavior and demonstrate the effect of exposed facet on surface adsorption and bulk phase diffusion of ions. Batch experimental results demonstrated that LFP (010), despite having a significantly smaller surface area, exhibits superior adsorption performance, with an adsorption capacity of 11.13 mg/g in a 50 ppm Li+ solution. Computational investigation reveals that due to the different exposed facets, the adsorption energy of Li(H2O)4+ on the LFP (010) is higher, but the immigration energies of Li+ in LFP (010) bulk phase are significantly lower (0.12 eV), leading to different adsorption rates at different time intervals. All these findings suggest that the adsorption process of Li+ is significantly crystal facet dependent, influenced by the adsorption energy and migration pathway, reflected in two stages of Li+ surface adsorption and bulk phase migration. These findings contribute to a better understanding of the interface interaction between Li+ and the adsorbent at the microscopic level and facilitate the design of more efficient adsorbents.

Composite solid-state electrolytes with fast ion channels constructed from in-situ hydrogen bonding and coupling/crosslinking effects for dendrite-free solid-state lithium batteries

All-solid-state lithium battery (ALLSB) with organic/inorganic composite solid-state electrolyte (CSSE) is one of the candidates for future energy storage due to the high specific energy and safety. However, large impedances and incompatibilities at the rigid electrode/electrolyte and internal interfaces of CSSE remain stumbling blocks for the spread of ASSLB. Acrylamide (AM)-contained (3-methacrylamidopropyl) triethoxysilane (MTS) is incorporated into CSSE to optimize the interfaces and modulate the ion diffusion and deposition behaviors based on the in-situ synergy effects of coupling/crosslinking and hydrogen bonding. Multiple hydrogen bonds between CSSEs and polar AM groups construct diverse Li interactions and facilitate dissociation and diffusion of Li. Coupling/crosslinking effect of the MTS can in-situ rearrange the above diversified Li environment. In turn, hydrogen bonds strengthen the coupling effect to the interface. The synergistic function contributes to favorable interfacial compatibility and stability, establishing a fast ion transport channel in the ASSLB. The MTS-intervened CSSE exhibits superior electrochemical and thermal properties. Li symmetric cells with this functional CSSE demonstrate stable lithium deposition/extraction for up to 2000 h. Moreover, the Li|LiFePO4 battery retains 91.7 % of its capacity after 500 cycles. This in-situ synergistic regulation provides a rational and simple guide for enhancing interface stability in CSSE and ASSLB.

Hydrogel electrolyte membrane with regulated pore effect to stabilize zinc anode in aqueous zinc-ion batteries

The unregulated dendrite growth and deleterious derivative reactions at Zn anodes lie in the path of research and industrialization of aqueous Zn-ion batteries (AZBs). The pore of the separator is a natural sieve for ion diffusion, but the high energy barrier for transmembrane transport can cause the “bridging” effect of ion congestion at the pore entrance, and induce the incubation of dendrites instead. In this work, a continuous, stable and fast ion transport channel is constructed by in-situ guided cross-linking of zinc alginate (ZA) hydrogels through the porous membrane to conquer the negative pore effect. The homogeneity and continuity of the channel structure, as well as the high ionic conductivity and zincophilicity of the ZA, can homogenize the electric field and reduce the energy barrier for ion transport. In battery systems, the physical ion shunting effect of a homogeneous pore structure, combined with the chemical/electrochemical effects of ZA guiding the diffusion of Zn2+ and binding free water, combat zinc dendrites and interfacial side reactions. The novel electrolyte membrane enables a highly reversible Zn plating/stripping to stabilize the Zn anode. This work provides illuminating insights into the regulation and application of pore effects in porous electrolyte membranes in metal-based batteries.

Na2.60Fe1.70(SO4)3 particles embedded in cross-linked graphene oxide networks as high-performance dual-electrode for sodium-ion batteries

Sodium iron sulfate materials have been initially applied to sodium ion batteries (SIBs) owing to their high operating voltage and stable electrochemical properties, yet poor conductivity and low theoretical capacity limit its commercial development. Herein, we first prepared Na2.60Fe1.70(SO4)3@graphene oxide (GO) composite via a facile solid-phase ball milling strategy, which are Na2.60Fe1.70(SO4)3 particles embedded in cross-linked GO networks. For the cathode of SIBs, the active particles in the material are wrapped with cross-linked GO networks that increases the electrolyte penetration and ion transport channels as well as improves electronic conductivity, resulting in a high operating voltage of 3.74 V and excellent cycle stability (retains over 70 % of capacity after 500 cycles at 8 C). Notably, the as-prepared material could exhibit a reversible capacity of 100 mAh g−1 after 100 cycles at 0.2 C as anode for SIBs. Furthermore, the material was first used to assemble symmetric sodium-ion full cell, demonstrating excellent electrochemical performance (achieving 60 mAh g−1 at 0.2 C). The Na2.60Fe1.70(SO4)3 particles wrapped with cross-linked GO networks offer a simple and effective approach to enhance the performance of SIBs, making an important contribution towards their practical industrial application.

Amino-grafted MOF-based composite membranes for improving Li+/Mg2+ separation performance

Advanced ion transportation channels aided by charge and suitable aperture play a crucial role in achieving precise separation of ions. Here, we report a MOF composite membrane with electropositive surface and sub-nanometer-sized ion transport channels for efficient Li+/Mg2+ separation. The membranes were fabricated using MOF “porous monomers” and trimesoyl chloride (TMC) through interfacial polymerization, and subsequently modified with amino-functionalized polyethyleneimine (PEI). The abundant porosity of the MOFs composite membrane includes the inner and the intergranular pores of MOF provided a rapid transport channel for Li+ ions, and a superior Li+ permeation rate of 0.68 mol m−2h−1 (a 10 times enhancement compared to the currently leading MOF membranes). Moreover, the improved positively charged surface (from −78 mV to + 4 mV at pH = 7) and reduced mean pore diameter (from 1.13 nm to 0.8 nm) of the membrane caused a remarkable selectivity of 13.2 for Li+/Mg2+. The design concept of the above MOFs based membrane provides a novel approach for developing high-quality MOF composite membranes for improving Li+/Mg2+ separation performance.

A facile strategy for the preparation of carbon nanotubes/polybutadiene crosslinked composite membrane and its application in osmotic energy harvesting

The osmotic energy between riverine water and seawater can be converted into electricity by reverse electrodialysis (RED). However, the facile fabrication of advanced RED membranes with high energy conversion efficiencies, large areas, and excellent mechanical properties remains a challenge. Carbon nanotubes (CNTs) exhibit excellent conductivity and provide suitable channels for ion transport but cannot form membranes independently, which limits the related applications in osmotic energy conversion. Herein, a new organic–inorganic composite membrane is prepared by combining hydroxyl-terminated polybutadiene as a matrix and carbon nanotubes as transport nanochannels. The nanotubes are pre-subjected to plasma treatment to increase the surface charge density and transport capacity of the nanochannels, improving the ion selectivity and energy conversion efficiency. Under actual seawater/river water conditions, the developed membrane delivers a power density of ∼5.1 W/m2 and shows good mechanical strength (219 MPa). Our work provides a facile solution to the problem posed by the inability of ideal nanochannels to form membranes independently and paves the way for the application of RED membranes in osmotic energy conversion.

Solid Polymer Electrolytes with Dual Anion Synergy and Twofold Reinforcement Effect for All-Solid-State Lithium Batteries.

Solid polymer electrolytes (SPEs) have emerged as a viable alternative to traditional organic liquid-based electrolytes for high energy density and safer lithium batteries. Poly(ethylene oxide) (PEO)-based SPEs are considered one of the mainstream SPE materials with excellent dissociation ability of lithium salts. However, the inferior ionic conductivity at room temperature and poor dimensional stability at high temperature limit their utilization. In this work, a semi-interpenetrating polymer network (semi-IPN) forming a precursor based on an ionic liquid (IL) monomer and linear PEO chains were introduced into an electrospun poly(acrylonitrile) (PAN) fibrous mat with subsequent thermal-initiated cross-linking. 1,4-Diazabicyclo [2.2.2] octane (DABCO) and 4-(chloromethyl) styrene were used to synthesize the styrenic-DABCO-based IL monomer with bis(trifluoromethane sulfonyl)imide (TFSI-) or bis(fluoromethane sulfonyl)imide (FSI-) as the anion, named as SDTFSI and SDFSI, respectively. Together, the FSI- and TFSI- anions demonstrate a synergistic effect in providing ion-conductive LiF and Li3N-rich inorganic SEI layer with enhanced lithium dendrite suppression ability. The twofold reinforcement effect is achieved collectively from the semi-IPN structure and the three-dimensional (3D) PAN network that help to construct highly efficient and uniform ion transport channels with excellent flexibility, further suppressing the lithium dendrite growth. The SPEs were dimensionally stable even at elevated temperatures of 150 °C. Moreover, the SPEs show an ionic conductivity of 4.4 × 10-4 S cm-1 at 25 °C and 1.81 × 10-3 S cm-1 at 55 °C and a lithium-ion transference number of 0.56. The favorable electrochemical performance of the SPEs was verified by operating LiFePO4/Li and NMC/Li cells.

Pyrrolidinium-functionalized Cardo (TPM) poly(arylene ether sulfone)s membranes for acid recovery: The effects of Cardo (TPM) microstructures

To explore the intrinsic correlation between the rigidity and distortion degree of polymer backbones and the diffusion dialysis (DD) performance of anion exchange membranes (AEMs), pyrrolidinium-functionalized poly(arylene ether sulfone)s containing different Cardo (TPM) moieties were prepared. The structures, properties and DD performance of above AEMs were systematically evaluated. As the Cardo (TPM) group angle increased, the d-spacing, fractional free volume, and membrane area resistance increased, and the microphase separation structures, hydrophilicity, and acid flux decreased, mainly because larger Cardo (TPM) group angles are unfavourable for the close packing of polymer chains in space. Both the Cardo-type and TPM-type AEMs exhibited universal ultrahigh H+/Fe2+ selectivity (S > 3819), which was mainly attributed to the synergistic influence of their rigid narrow ion transport channels, small pore diameter (0.48–0.62 nm) and narrow pore size distribution (0.24–0.68 Å). Additionally, due to the high-density amide groups of TPM units, which decreased the hydrophobicity of the polymer skeleton and induced the formation of an additional transport pathway for Fe2+ through hydrogen bonding interactions, the TPM-type AEMs showed both lower acid flux and selectivity, suggesting that the structure of hydrophilic auxiliary groups should be carefully designed when improving the DD performance of AEMs.