Layered Double Hydroxides Layers Research Articles

Development of a low carbon binder system based on metakaolin: Focus on corrosion inhibitor-intercalated layered double hydroxides

In this work, MgO-CaO activated blends were produced by using metakaolin (MK). Roles of sodium nitrite (NaNO2) corrosion inhibitor on phase assemblance, micro-structure, and chloride binding of layered double hydroxides (LDH) in the systems were systematically studied. The results showed that the compressive strength in the middle and late stages were increased for 32.78% and 73.74% with the addition of CaO, and pore structure of the MgO-CaO-MK blends was optimized. After the addition of 5% NaNO2, NO2− anions were preferably intercalated into the layers of self-formed MgAl LDH and CaAl LDH. The chloride binding capacity of the samples was stronger than that of cement paste, which was attributed to the generation of more LDH by accelerating hydration of the system.

Desorption behavior of phosphate species from layered double hydroxides

In phosphate species recovery, layered double hydroxides (LDHs) are good adsorbent, but show difficulties in its desorption. In this study, the desorption behavior was systematically investigated by changing several factors, which were drying condition, change with time, crystallinity and solution for desorption. Interlayer space of PO4-exchanged LDHs could swell by adding water one day after synthesis when the LDHs were vacuum dried at 25 °C. However, the swelling ability was deteriorating with time, and was also lost by oven-drying at 110 °C. In the case of high-crystallinity LDH, clear results were observed: desorption ratio of phosphate species from the vacuum-dried LDH decreased with time even by 1 M NaOH which was the most effective, and desorption ratios of phosphate species from the oven-dried LDH dropped sharply. In contrast, SO4-exchanged LDH, which were used for comparison, did not lose their swelling ability, and desorption ratios of sulphate were almost unchanged over time or by oven-drying at 110 °C. PO4-exchanged LDH stored in aqueous suspensions did not lose their swelling ability with time, and their desorption ratios of phosphate species remained unchanged over time. Therefore, above results suggest that interaction between phosphate species and host layers of LDHs in dried state causes the changes. In conclusion, the result that phosphate species desorption from dried high-crystallinity LDH deteriorated with time has not been reported previously, which will give a great impact on applications such as recovery of phosphate and slow release of phosphate.

A Novel Coating System Based on Layered Double Hydroxide/HQS Hierarchical Structure for Reliable Protection of Mg Alloy: Electrochemical and Computational Perspectives.

Growing research activity on layered double hydroxide (LDH)-based materials for novel applications has been increasing; however, promoting LDH layer growth and examining its morphologies without resorting to extreme pressure conditions remains a challenge. In the present study, we enhance LDH growth and morphology examination without extreme pressure conditions. By synthesizing Mg-Al LDH directly on plasma electrolytic oxidation (PEO)-treated Mg alloy surfaces and pores at ambient pressure, the direct synthesis was achieved feasibly without autoclave requirements, employing a suitable chelating agent. Additionally, enhancing corrosion resistance involved incorporating electron donor-acceptor compounds into a protective layer, with 8-Hydroxyquinoline-5-sulfonic acid (HQS) that helps in augmenting Mg alloy corrosion resistance through the combination of LDH ion-exchange ability and the organic layer. DFT simulations were used to explain the mutual interactions in the LDH system and provide a theoretical knowledge of the interfacial process at the molecular level.

Tungstate Intercalated NiFe Layered Double Hydroxide Enables Long-Term Alkaline Seawater Oxidation.

Renewable electricity-driven seawater splitting presents a green, effective, and promising strategy for building hydrogen (H2 )-based energy systems (e.g., storing wind power as H2 ), especially in many coastal cities. The abundance of Cl- in seawater, however, will cause severe corrosion of anode catalyst during the seawater electrolysis, and thus affect the long-term stability of the catalyst. Herein, seawater oxidation performances of NiFe layered double hydroxides (LDH), a classic oxygen (O2 ) evolution material, can be boosted by employing tungstate (WO4 2- ) as the intercalated guest. Notably, insertion of WO4 2- to LDH layers upgrades the reaction kinetics and selectivity, attaining higher current densities with ≈100% O2 generation efficiency in alkaline seawater. Moreover, after a 350h test at 1000mAcm-2 , only trace active chlorine can be detected in the electrolyte. Additionally, O2 evolution follows lattice oxygen mechanism on NiFe LDH with intercalated WO4 2- .

Waterborne epoxy coating with excellent barrier and self-healing properties for long-term corrosion protection

Herein, an intelligent anticorrosive coating with superior barrier and self-healing properties was prepared. Molybdate (MoO42−) intercalated layered double hydroxide (MIH) was synthesised and polydopamine (PDA) shell was grown on MIH surface to prepare MIH@PDA (PMIH) material. PMIH was assembled on graphene (Gr) sheet through π–π interaction to obtain the Gr@PMIH composite. The anticorrosive coating was prepared by incorporating Gr@PMIH into the epoxy resin. The PMIH material demonstrated a stimulus-response capacity due to the solubility of polydopamine in acidic conditions. In addition, the ion-exchange properties of the layered double hydroxide (LDH) facilitated the release of the encapsulated molybdate corrosion inhibitor between LDH layers and the adsorption of chloride ions. This mechanism was corroborated by ultraviolet–visible (UV–vis) spectroscopy results. Electrochemical impedance spectroscopy (EIS) results revealed that the incorporation of MIH and Gr@PMIH materials considerably enhanced the low-frequency (0.01 Hz) impedance modulus. Among the tested ratios, Gr@PMIH/waterborne epoxy coatings (WECs) (3:7) exhibited the most effectively long-term corrosion protection. EIS measurements of the scratched coatings confirm the superior corrosion resistance and inhibition properties of Gr@PMIH/WECs (3:7). Furthermore, after 400 h of salt spray testing, substrates coated with Gr@PMIH/WECs (3:7) showed the least amount of corrosion products and blisters around surface scratches, affirming its exceptional long-term corrosion protection performance. Thus, the excellent barrier and stimuli-responsive characteristics of the Gr@PMIH material endowed the coating with enhanced long-term corrosion resistance and intelligent protection capabilities.

Preparation of hydrophobic layered double hydroxide-based composite pigments via octyltriethoxysilane surface modification for cosmetic applications.

Pigments play a pivotal role in the cosmetic industry, in which the development of pigments with concurrent color diversity, hydrophobicity, biocompatibility and photostability remains a great challenge. Herein, we report organic-inorganic composite pigments synthesized via a combination of organic dye anions (Ponceau SX and acid green (AG)), layered double hydroxides (LDHs) and octyltriethoxysilane (OTEOS) (denoted as O/Dye-LDHs: O/SX-LDHs and O/AG-LDHs).The prepared composite pigments were characterized via a comprehensive investigation based on X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS-mapping), Fourier transform infrared (FT-IR) spectroscopy, CIE 1976 L*a*b* color scales, static contact angle measurement and HET-CAM assay. The results confirm the successful intercalation of organic dye anions into the interlayer region of LDHs via host-guest interactions and the surface modification of OTEOS on the layer surface, forming a new kind of hydrophobic organic-inorganic composite pigment with a sandwich structure. LDH layer protection and OTEOS coating play crucial roles in the high photostability, good hydrophobicity and satisfactory biocompatibility of pigments. In addition, O/Dye-LDHs exhibit rich color and color adjustability. Impressively, we applied mixture composite pigments with different O/SX-LDH-to-O/AG-LDH ratios to formulate an eye shadow cream, which present a series of popular and natural colours with water resistance to enhance one's attractiveness and appearance. This work provides a promising strategy for the design of safe and efficient composite pigments, demonstrating their potential application in the field of makeup.

Multifunctional Biocompatible Nanoparticles: Surface Modification and Synthesis of Layered Double Hydroxides for Biomedical Applications

Layered Double Hydroxides (LDHs) are considered versatile materials owing to their distinctive features resulting from the isomorphous substitution of metal cations, namely M(II) and M(III), inside their octahedral locations. The LDH layer structure is characterized by a balanced arrangement of exchangeable hydrated or solvated anions within the interlayer and outer regions. This arrangement gives rise to a two-dimensional heterostructure with an ABAB pattern. Various metal cations have a role in LDHs composition, leading to their classification as hydrocalumites and hydrotalcite. Pristine-LDHs that include diverse inorganic anions have shown significant potential in biological applications. These substances have been investigated for their potential use in many applications, including but not limited to antacids, vaccination adjuvants, etc. The attainment of monodispersity in the size of LDHs is of utmost importance for their efficacy in biomedicine. This research emphasizes that the potential of LDHs is contingent upon effectively resolving difficulties, including those associated with size polydispersity. This study suggests using Surface Modified and Synthesized Layered Double Hydroxides for Biomedical Applications (SMS-LDH-BMA). The present study presents a novel approach that incorporates various enhancements, such as a decreased hydrodynamic diameter of 44.6 nm, a zeta potential of -23.86 mV, a high encapsulation efficiency of 91.2%, a substantial drug loading capacity of 14.6%, a favorable cell viability of 96.44%, and a controlled release rate of GLIB at 3.73 μg/mL/min. These findings demonstrate the efficacy of SMS-LDH-BMA in tackling these obstacles and augmenting the drug delivery capabilities and biomedical applications of LDHs.

Improving corrosion and wear resistances of 2195 Al–Li alloy by PEO and LDHs composite coating

In this study, a composite coating comprising a ceramic film and layered double hydroxide (LDHs) layer was prepared on the surface of extruded 2195 Al–Li alloy. The preparation method, surface morphology, and chemical composition of the coating were described and characterized in detail. The corrosion and wear protection of the coating on the Al–Li alloy substrate were tested, and the mechanisms of corrosion and wear resistance were discussed. The results indicate that plasma electrolytic oxidation processing can form a thick ceramic film with good interface bonding on the surface of 2195 Al–Li alloy. Hydrothermal reaction in an alkaline solution produces a nanoscale layer of Mg/Al LDHs on the surface of the ceramic film. The LDHs layer fills the micro-pores and cracks in the film and effectively prevents the corrosion medium from permeating and damaging the alloy matrix. The composite coating reduces the surface corrosion efficiency by 99.98 %. Moreover, the composite-coated samples exhibit long-lasting corrosion resistance in seawater and exfoliation corrosion environments. Additionally, the composite-coated Al–Li alloy exhibits wear resistance 1-2 orders of magnitude higher than that of the bare alloy at both room and high temperatures. This study proposes a novel strategy for corrosion and wear protection of Al–Li alloys.

Influence of Mg substrate on the formation mechanism and corrosion resistance of LDH films

Layered double hydroxides (LDH) layer has been synthesized on various Mg substrates (pure Mg, MgLi and AZ91 alloy) under atmospheric pressure. Presence of alloying elements resulted in formation of a new composition and accelerated film growth rate. Li promoted homogeneous growth of LDH film, while the cathodic intermetallics in AZ91 Mg resulted in heterogeneous growth and formation of a porous LDH film, leading to deteriorated corrosion resistance. The dense MgLi LDH layer demonstrated high impedance value (4030 Ω·cm2) after 240 h electrochemical impedance spectroscopy (EIS) test, which was much higher than that of the substrate (146 Ω·cm2).

Study on the Thermal Stabilizing Process of Layered Double Hydroxides in PVC Resin

Poly(vinyl chloride) (PVC) is widely used in various fields and requires the use of thermal stabilizers to enhance its thermal stability during processing because of its poor thermal stability. Layered double hydroxides (LDHs) are widely considered to be one kind of highly efficient and environmentally friendly PVC thermal stabilizer. To investigate the thermal stabilizing process of layered double hydroxides (LDHs) in PVC resin, PVC and MgAl-LDHs powders with different interlayer anions (CO32−, Cl−, and NO3−) were physically mixed and aged at 180 °C. The structure of LDHs at different aging times was studied using XRD, SEM, and FT-IR. The results show that the thermal stabilizing process of LDHs on PVC mainly has three stages. In the first stage, the layers of LDHs undergo a reaction with HCl, which is released during the thermal decomposition of PVC. Subsequently, the ion exchange process occurs between Cl− and interlayer CO32−, resulting in the formation of MgAl-Cl-LDHs. Finally, the layers of MgAl-Cl-LDHs react with HCl slowly. During the thermal stabilizing process of MgAl-Cl-LDHs, the peak intensity of XRD reduces slightly, and no new XRD peak emerges. It indicates that only the first step happens for MgAl-Cl-LDHs. The TG-DTA analysis of LDHs indicates that the interaction of LDHs with different interlayer anions has the following order: NO3− < CO32− < Cl−, according to the early coloring in the thermal aging test of PVC composites. The results of the thermal aging tests suggest that LDHs with a weak interaction between interlayer anions and layers can enhance the early stability of PVC significantly. Furthermore, the thermal aging test demonstrates that LDHs with high HCl absorption capacities exhibit superior long-term stabilizing effects on PVC resin. This finding provides a valuable hint for designing an LDHs/PVC resin with a novel structure and excellent thermal stability.

Layered double hydroxide loaded pinecone biochar as adsorbent for heavy metals and phosphate ion removal from water

This study modified pinecone biochar with a novel layered double hydroxide (LDH) to enhance its capacity to adsorb heavy metal and phosphate ions from water. The unmodified pinecone biochar demonstrated moderate adsorption capacities for Cu2+ (25.0 mg/g), Co2+ (24 mg/g), Pb2+ (22.9 mg/g), and phosphate (36.0 mg/g). However, after LDH modification, the LDH-biochar showed significantly improved adsorption capacities for Pb2+ (135.9 mg/g) and phosphate (160.8 mg/g) and a slight increase for Cu2+ (30.6 mg/g) and Co2+ (28.0 mg/g). The LDH layer enhances the adsorption of Pb2+ through ion exchange, phosphate through surface precipitation, and Cu2+ and Co2+ through surface complexation. The integration of LDH creates a multifaceted layer that utilizes various mechanisms to boost the biochar's adsorption capacity.

Phase‐Bridged Hierarchical Catalysts for Efficient and Stable Water Electrolysis

AbstractThe design and synthesis of low‐cost electrocatalysts with high catalytic activity and long‐term stability is a challenging task. This study utilizes a combination of electronic tuning and surface reconstruction to synthesize a ternary layered double hydroxide (LDH)/phosphide (P−NiCuFe−LDH) hierarchical‐structure catalyst that improves the kinetics of the hydrogen/oxygen evolution reactions in water electrolysis by facilitating the thermodynamically limited reaction pathways. Spectroscopic analyses indicate synergistic electronic interactions among the metal atoms in the LDH and phosphide layers via the P‐bridge effect. This cross‐layer interaction optimizes the electron transport pathways and reaction kinetics, enabling the proposed hierarchical electrocatalyst to exhibit high intrinsic activity. Theoretical calculations confirm the configuration of the cross‐phase bridges and elucidate the origin of the enhanced electrocatalytic effect of P−NiCuFe−LDH. For overall water splitting, the P−NiCuFe0.06−LDH || P−NiCuFe0.06−LDH system requires only 1.517 V to attain a current density of 10 mA cm−2. The P−O‐containing surface (generated in situ during water electrolysis) prevents metal‐ion leaching and endows P−NiCuFe−LDH with excellent operational stability; as demonstrated by the continuous long‐term stability test over 1000 h with negligible performance degradation. This study provides important insights into the design of rational hierarchical structures for a wide range of applications beyond water splitting.

Controlled molecular arrangement of easily aggregated deoxycholate with layered double hydroxide.

Deoxycholate (DA) is a natural emulsifying agent involved in the absorption of dietary lipids. Due to the facial distribution of hydrophobic-hydrophilic region, DA easily aggregates under ambient conditions, and this property hinders the practical application of DA in clinical applications. In this study, we found that the molecular arrangement of DA molecules could be controlled by using layered double hydroxide (LDH) under a specific reaction condition. The effect of reaction methods such as co-precipitation, ion exchange and reconstruction on the molecular arrangement of DA was investigated by X-ray diffraction, Fourier-transform infrared spectroscopy, high-resolution transmission electron microscopy and differential scanning calorimetry. It was demonstrated that the self-aggregation of DA molecules could be suppressed by the oriented arrangement of DA between the gallery space of LDH. The DA moiety was well stabilized in the LDH layers due to the electrostatic interaction between DA molecules and LDH layers. The most ordered arrangement of DA molecules was observed when DA was incorporated into LDH via a reconstruction method. The DA molecules arranged in LDH via reconstruction did not show significant exothermic or endothermic behaviour up to 400°C, showing that the DA moiety lost its intermolecular attraction in between LDH layers.

Construction of a PEO/Mg–Mn LDH composite coating on Mg–Ag–Mn alloy for enhanced corrosion resistance and antibacterial potential

Endowing magnesium alloys with both durable antibacterial ability and reliable corrosion resistance is an urgent task for the development of magnesium-based implants. In this work, Mg–Mn layered double hydroxide (LDH) intercalated with organic salicylic acid (SA) anion was synthesized on a PEO-coated Mg–Ag–Mn alloy via the combination of co-precipitation and hydrothermal treatments. The PEO layer endows Mg–Ag–Mn alloy with a moderate corrosion barrier and the Mg–Mn LDH layer not only seals the PEO defects, but also acts as a reservoir for antibacterial agents (namely SA). The PEO/Mg–Mn LDH composite coating on Mg–Ag–Mn alloy dramatically increases its corrosion resistance by up to 3 orders of magnitudes, which also tailors the ionic release kinetics for a desired antibacterial potential to prevent bacterial infection.

Purpurin intercalated layered double hydroxide nanocomposites for improved CO2 visible photocatalytic reduction: Dye-intercalation stabilization and sensitization

Purpurin(pp) can be used as a photosensitive molecule in photocatalytic systems due to its excellent absorption of visible light, but its application is limited due to its poor stability under light. Layered double hydroxides (LDHs) can act as molecular containers due to their interlayer anion exchangeability, introducing target anions into the interlayer of LDHs and improving the instability of anions by utilizing the 2D confinement environment between LDHs layers. A series of co-intercalation materials with different ratios of pp and dodecyl sulfonate (SDS) were prepared through the hydrothermal method in this work, denoted as SDS-pp(x%)/LDHs. Compared with pp, the absorbance retention rate of SDS-pp(x%)/LDHs increased from 12.5% to 90% after 5 h of light exposure. Then its potential application in visible photocatalytic reduction of CO2 was explored. When the intercalation ratio of pp is 3%, the performance is optimal. Compared with ZnAl LDHs, the yield of CO produced by SDS-pp(3%)/LDHs was increased by 12 times and a small amount of 8-electron reduction product CH4 appeared. Through mechanism exploration, the matching energy level relationship between pp and LDHs promotes electron transfer from pp to LDHs. In addition, the catalyst exhibits good cyclic photocatalytic reduction performance for CO2 due to its stable intercalation structure.

Glucose pillared Ni-Co layered double hydroxide clay materials toward durable cathodes for alkaline zinc batteries

Alkaline Ni-Zn batteries are gaining more and more attention because of their safety, environmental friendliness, low cost and excellent performance. However, the volume and structure of the cathode changes during the charging and discharging process, resulting in particle flaking and structural rupture during the cyclic charging and discharging process, thus reducing their cyclic stability and limiting wide application. Herein, NiCo Layered double hydroxides (LDHs)clay materials with a low crystallinity multilayer nanosheet structure are prepared by glucose intercalation as cathode materials for alkaline Ni-Zn batteries. Expanded NiCo LDH layer spacing through glucose intercalation reduces interlayer peeling and collapse, accelerates interlayer diffusion of ions, and thus improves electron transport performance. NiCo LDH-G1.5 electrode material provides a specific capacity of 224 mAh g-1 and a capacity retention rate of 76% at a current density of 40 A g-1, 2000 cycles to maintain 86% of maximum capacity. Alkaline NiCo LDH-G1.5//Zn battery, a specific capacity of 180 mAh g-1 can be achieved at a high current density of 20 A g-1 and still maintain 76% of their maximum capacity after 2000 cycles, a maximum energy density of 364 Wh kg-1 and a maximum power density of 54 kW kg-1. This work provides a viable cathode for the development of high specific capacity and stable alkaline Ni-Zn batteries.

Facile synthesis of visible-responsive photocatalytic Eu-doped layered double hydroxide for selective removal of NOx pollutant

Efficient nitrogen oxides (NOx) removal from the urban atmosphere is still a target for the researchers. Herein, a Zn2Al-CO3 based layered double hydroxide (LDH) was doped with increasing amounts of Eu3+ (0.01–0.04) and the photocatalytic oxidation of NOx gases was investigated. The LDHs were synthesized by a facile coprecipitation method at room temperature and ambient pressure. The successful Eu3+ substitution in the LDH layers induces a shift in the M−O bonds that modifies the electronic band structure of the doped photocatalysts. Compared to the undoped LDH, the NOx removal efficiency was enhanced by ∼ 17–25 % under UV–Vis light irradiation. Remarkably, a NOx removal efficiency of ∼ 47 % was attained by the optimally doped LDH under Visible irradiation (420 nm), surpassing raw LDH (∼ 9 %). Moreover, the Eu3+ doped LDHs retained its photocatalytic efficiency during long periods of irradiation during consecutive tests with high selectivity (>90 %). Photoluminescence studies indicated that Eu3+ was located in a non-centrosymmetric position, thereby producing structural disorder within the lattice. Eu doping promoted charge separation and a higher production of ⋅OH radicals as verified by time-resolved photoluminescence and electron paramagnetic resonance, respectively. We believe this work reports unprecedent results obtained by Eu-doping of Zn2Al-based LDHs under visible light for NOx photooxidation and serves as a new strategy to prepare functional LDHs for other photocatalytic applications.

Two‐Dimensional LDH Film Templating for Controlled Preparation and Performance Enhancement of Polyamide Nanofiltration Membranes

AbstractTailored design of high‐performance nanofiltration membranes that can be used in a variety of applications such as water desalination, resource recovery, and sewage treatment is desirable. Herein, we describe the use of layered double hydroxides (LDH) intermediate layer to control the interfacial polymerization between trimesoyl chloride (TMC) and piperazine (PIP) for the preparation of polyamide (PA) membrane. The dense surface of LDH layer and its unique mass transfer behavior influence the diffusion of PIP, and the supporting role of the LDH layer allows the formation of ultrathin PA membranes. By only changing the concentration of PIP, a series of membranes with controllable thickness from 10 to 50 nm and tunable crosslinking‐degree can be prepared. The membrane prepared with a higher concentration of PIP shows excellent performance for divalent salt retention with water permeance of 28 Lm−2 h−1 bar−1, high rejection of 95.1 % for MgCl2 and 97.1 % for Na2SO4. While the membrane obtained with a lower concentration of PIP can sieve dye molecules of different sizes with a flux of up to 70 Lm−2 h−1 bar−1. This work demonstrates a novel strategy for the controllable preparation of high‐performance nanofiltration membranes and provides new insights into how the intermediate layer affects the IP reaction and the final separation performance.

Two-dimensional LDH films templating for controlled preparation and performance enhancement of polyamide nanofiltration membranes.

Tailored design of high-performance nanofiltration membranes that can be used in a variety of applications such as water desalination, resource recovery, and sewage treatment is desirable. Herein, we describe the use of layered double hydroxides (LDH) intermediate layer to control the interfacial polymerization between trimesoyl chloride (TMC) and piperazine (PIP) for the preparation of polyamide (PA) membrane. The dense surface of LDH layer and its unique mass transfer behavior influence the diffusion of PIP, and the supporting role of the LDH layer allows the formation of ultrathin PA membranes. By only changing the concentration of PIP, a series of membranes with controllable thickness from 10 to 50 nm and tunable crosslinking-degree can be prepared. The membrane prepared with a higher concentration of PIP shows excellent performance for divalent salt retention with water permeance of 28 Lm-2h-1bar-1, high rejection of 95.1% for MgCl2 and 97.1% for Na2SO4. While the membrane obtained with a lower concentration of PIP can sieve dye molecules of different sizes with a flux of 70 Lm-2h-1bar-1. This work demonstrates a novel strategy for the controllable preparation of high-performancemembranes and provides new insights into how the intermediate layer affects the IP reaction and the final separation performance.

Cooperative Lithium Sorption in Doped Layered Double Hydroxides Is Modulated by Colloidal (Dis)Assembly

Lithium–aluminum layered double hydroxides (LDHs) selectively sorb lithium from brines, concentrating and purifying this critical element for subsequent conversion to active battery components. Lithium ion partitioning into lattice vacancies within the LDH structure is selectively enhanced with iron doping. However, this process leads to a highly coupled set of intercalation interactions whose mechanisms are challenging to assess in situ. Here, we show that iron modulates the size- and shape-dependent composition of LDHs and imposes a powerful control on lithium sorption processes in complex fluids. We observe fundamental units of LDH layers and aluminum ferrihydrite nanoclusters that (dis)assemble to form at least five distinct particle types that influence LDH lithium capacity and cyclability. Importantly, lithium sorption is controlled by feedbacks arising from the dynamic interconversion of planar stacks and scrolls of LDH layers, which exchange lithium, water, and other species in the process of (un)rolling due to similar energy scales of hydration, sorption, and deformation. Under appropriate iron redox conditions, the cycling efficiency and stability of lithium sorption can be optimized for the range of lithium concentrations found in many natural brines.