Ni Al LDHs Research Articles

Carbon-Dots-Modified Hierarchical ZnIn2S4/Ni-Al LDH Heterojunction with Boosted Charge Transfer for Visible-Light-Driven Photocatalytic H2 Evolution.

The construction of a heterojunction structure is considered a significant route to promote solar-driven H2 production. Herein, a CDs/ZnIn2S4/Ni-Al LDHs (CDZNA) ternary heterojunction was elaborately constructed via the in situ growth of ZnIn2S4 on Ni-Al LDHs with the incorporation of carbon dots (CDs) cocatalyst, which was used as a highly efficient catalyst for the photocatalytic H2 generation. Characterizations indicated that 2D ZnIn2S4 nanosheet homogeneously dispersed on the surface of Ni-Al LDHs fabricated an intimate hierarchical architecture and provided a high BET surface area (135.12 m2 g-1). In addition, the unique embeddable-dispersed CDs as electron mediators possessed numerous active sites and promoted the charge separation on ZnIn2S4/Ni-Al LDHs (ZNA) binary catalyst. By coupling these two features, the CDZNA catalyst exhibited a considerable H2 production rate of 23.1 mmol g-1 h-1 under visible-light illumination, which was 16.4 and 1.4 times higher than those of ZnIn2S4 and ZNA, respectively. A proposed mechanism of photocatalytic H2 production over the CDZNA catalyst was also discussed. This work provides a promising strategy to achieve highly efficient solar energy conversion in a ternary photocatalytic system.

Ni-Al layered double hydroxide-coupled layered mesoporous titanium dioxide (Ni-Al LDH/LM-TiO2) composites with integrated adsorption-photocatalysis performance.

Nickel aluminum layered double hydroxides (Ni-Al LDHs) and layered mesoporous titanium dioxide (LM-TiO2) were prepared via a simple precipitation process and novel precipitation-peptization method, respectively, and Ni-Al LDH-coupled LM-TiO2 (Ni-Al LDH/LM-TiO2) composites with dual adsorption and photodegradation properties were obtained via the hydrothermal approach. The adsorption and photocatalytic properties were investigated in detail with methyl orange as the target, and the coupling mechanism was systematically studied. The sample with the best performance was recovered after photocatalytic degradation, which was labeled as 11% Ni-Al LDH/LM TiO2(ST), and characterization and stability studies were carried out. The results showed that Ni-Al LDHs showed good adsorption for pollutants. Ni-Al LDH coupling enhanced the absorption of UV and visible light, and the transmission and separation of photogenerated carriers were also significantly promoted, which was conducive to improving the photocatalytic activity. After treatment in the dark for 30 min, the adsorption of methyl orange by 11% Ni-Al LDHs/LM-TiO2 reached 55.18%. Under illumination for 30 min, the decolorization rate of methyl orange solution reached 87.54%, and the composites also showed an excellent recycling performance and stability.

Dynamic Changes of Ni-Al LDH Nanosheets under Potential Cycling Investigated by In Situ Electrochemical Atomic Force Microscopy

Nickel-aluminum layered double hydroxides (Ni-Al LDHs) are widely used in energy storage and conversion devices, and the impact of the Ni/Al molar ratio on the structural evolution and kinetic process is of great significance for improving reaction kinetics and efficiency. In this paper, the morphological evolutions and nanomechanical property changes of Ni-Al-n LDH (n is the Ni/Al molar ratio) nanosheets during potential cycling were explored by in situ electrochemical atomic force microscopy. The conversion of Ni2+ into Ni3+ and the amphoteric properties of Al3+ during potential cycling resulted in the dissolution of Ni-Al-n LDH nanosheets. The dissolution rate of Ni-Al-2 LDH nanosheets was slower than those of Ni-Al-2.5 LDH and Ni-Al-3 LDH nanosheets. Meanwhile, the Young’s modulus value of the dissolved area was much larger than that of the undissolved area, and the dissolved area exhibited a harder property. It was attributed to the different microcrystalline structures of Ni-Al LDH nanosheets affected by the Ni/Al molar ratio and the rearrangement of Ni2+ and Al3+ during the reaction. The slow dissolution of Ni-Al-2 LDH nanosheets was beneficial to improving the electrochemical performance, while the fast dissolution of Ni-Al-2.5 LDH and Ni-Al-3 LDH nanosheets was not conducive to the electrochemical performance. Understanding the effect of the Ni/Al molar ratio on the morphological evolutions and nanomechanical property changes of Ni-Al LDH nanosheets during potential cycling has important guiding significance for the subtle compositional modification and structural design of Ni-Al LDHs as an electrode material.

Ni-Al layered double hydroxides electrodeposition from a chloride solution

Abstract Ni-Al LDHs was electrodeposited from a NiCl2-AlCl3 solution. In order to analyze the electrodeposition process, electrolytes with initial Al content range of 0–20% were used. With increasing Al content in the sample, the preferred orientations of (0 0 3) and (0 0 6), increased crystallinity, and decreased interlayer spacing were observed from the XRD results. A dissolution–recrystallization of (0 0 3) plane was detected among the Ni-Al LDHs from the strongly alkaline solution soaking results, which was found to be conducted easily in high Al-containing samples. The pH of the Al-containing electrolyte was much lower than that of pure NiCl2 solution because lower pH was needed to start a precipitation reaction in the AlCl3-NiCl2 solution. The electrodeposition yield and current efficiency were found to decrease obviously in the electrolytes with initial Al content higher than 10%, which was attributed to the increasing Al content in the sample and diffusion of the complex ions. The electrodeposition pattern was in-situ in the electrolyte initially containing 10% Al, then, it developed toward and off in-situ in electrolytes initially containing 0–10% and 10–20% Al.

From gradual change to abrupt change in Ni-Al layered double hydroxide memristor by adsorbed small molecule oxadiazole

The memristor based on Ni-Al layered double hydroxide (Ni-Al LDHs) was investigated. The memristor be composed of oxadiazole-adsorbing Ni-Al LDHs composite active layer was researched. Experimental results show that memristors characteristic could be modulated by adsorbing oxadiazole with Ni-Al LDHs in active layer from gradual change to abrupt changes in resistive switching. While, Ni-Al LDHs devices show gradual current changes, and its synaptic plasticity and spike-time-dependent plasticity in Hebbian learning has been investigated; the device with adsorbed oxadiazole small molecules undergoes abrupt changes. This study shows the potential of nanocomposites that adsorb electrically active small molecules to modify the resistive switching characteristics of memristors and paves the way for the design of nanocomposite memristors for use in advanced devices.

Ostensibly phosphatized NiAl LDHs nanoflowers with remarkable charge storage property for asymmetric supercapacitors

Improving conductivity of electron and ion was considered to be the significant tendency on pseudocapacitive materials. In this work, a flower-like P-NiAl LDHs electrode materials have been successfully fabricated by hydrothermal synthesis and subsequent phosphatized treatment. Owing to the presence of phosphide, the resulting P-NiAl LDHs electrode showed a high specific capacitance of 2159F g−1 at 1 A g−1 and a good capacitance retention of 85.6% at 20 A g−1, which more excellent than NiAl LDHs electrode. Besides, the P-NiAl LDHs//AC asymmetric supercapacitor exhibited a high energy density of 79.3 Wh kg−1 under a power density of 1033.6 W kg−1 and an acceptable stability of 73.6% specific capacitance retention after 2400 charge-discharge cycles. Consequently, the P-NiAl LDHs nanoflower is one of the better candidates for assembling supercapacitor, and this phosphatized method is a kind of facile and desirable strategies to improve the electrochemical characteristics of LDH-based supercapacitor materials.

Tremella-like NiAl-Layered double hydroxides anchored on polydopamine/reduced graphene oxide for supercapacitor with high energy density

The NiAl-layered double hydroxides (NiAl LDHs) has been known as a very desirable positive electrode material for alkaline supercapacitors due to it can provide a higher theoretical specific capacity than β-Ni(OH)2. However, NiAl LDHs is structurally unstable in an alkaline solution and can easily convert into another crystal (β-Ni(OH)2). Therefore, it is important to study and design the true active phase of the effective electrode material. In this work, we use high-valence Al ions to replace some of the Ni ions in the raw materials to stabilize its crystal structure and prepare the tremella-like NiAl LDHs decorated on polydopamine/reduced graphene oxide (NiAl LDHs@PDA/rGO) by a simple hydrothermal method. The NiAl LDHs@PDA/rGO exhibit high specific capacitance of 2210.7 F g−1 at 1 A g−1 and excellence rate performance (71% of capacitance retention with the increase of current density from 1 to 40 A g−1) as the cathode material for supercapacitor. Furthermore, the hybrid supercapacitor delivers a superior energy density of 58.93 W h Kg−1 at 800.21 W kg−1 and long cycling life. This work not only provides a simple method to prepare the tremella-like NiAl LDHs@PDA/rGO but also paves the way for the development of advanced cathode materials for the next generation of supercapacitors.

Preparation and evaluation of the Ca-Al layered double hydroxide for removal of copper(II), nickel(II), zinc(II), chromium(VI) and phosphate from aqueous solutions

Hydrocalumite (CaAl-LDH) was prepared by the co-precipitation method with different Ca2+/Al3+ molar ratios. Hydrocalumite at the molar ratio of 4:1 Ca2+/Al3+ (4HC) showed to be efficient in the removal of Cu2+, Ni2+ or Zn2+ from the aqueous solution. The products formed between 4HC and the Cu2+, Ni2+ or Zn2+ cations were characterized by atomic absorption, SEM, XRD and IR. The effect of several factors such as pH, dose, contact time and metal concentration were evaluated. The maximum removal capacity was 7.0mmolg−1 for Cu2+ and Ni2+, and 6.3mmolg−1 for Zn2+. X-ray diffraction analyses showed that the products formed were CuAl, NiAl and ZnAl LDHs. The 4HC also was applied for removal of metal cations and the oxyanions Cr(VI) or phosphate from the same solution. In solutions containing 400mgL−1 of Cu2+, Ni2+ or Zn2+ and 200mgL−1 of Cr(VI) or phosphate (expressed as phosphorus), and in the presence of 1gL−1 of 4HC, 100% of the metals and 60, 57 and 52% of Cr (VI) or 93, 80 and 92% of phosphate were removed, respectively. The results showed that 4HC has great potential to be used in the treatment of effluents containing metal cations and oxyanions.

Hierarchically magnetic Ni–Al binary layered double hydroxides: towards tunable dual electro/magneto-stimuli performances

Ni–Al layered double hydroxides (Ni–Al LDHs) are adopted as an electrorheological (ER) material ascribed to their special layered structure, ample polarizable groups and good dispersibility. The magnetite nanoparticles (Fe3O4 NPs) are utilized as classical magnetorheological (MR) materials on account of their excellent paramagnetic property. In this work, we report the rational design of high-performance ER/MR materials by integrating the structural merits of Fe3O4 NPs onto a binary layered structure system. The obtained Fe3O4/Ni–Al LDH NCs dispersed in silicone oil displayed appealing dual ER/MR performances. The work opens a new path toward novel stimuli-responsive materials for industrial applications.

Highly selective and efficient removal of arsenic(V), chromium(VI) and selenium(VI) oxyanions by layered double hydroxide intercalated with zwitterionic glycine

In this study, a new strategy for highly selective and extremely efficient removal of toxic oxyanions (Cr(VI), Se(VI), and As(V)) from aqueous solutions using zwitterionic glycine intercalated layered double hydroxide (Gly-LDH) was reported. Hence, to investigate the effect of zwitterionic glycine on the adsorption capacity, selectivity factor and adsorption mechanism of LDHs, two NiAl LDHs intercalated with different inter-layer anions, including NO3− and glycine, were synthesized. The obtained results show that the adsorption capacity and selectivity factor of oxyanions through ion exchange mechanism in NO3-LDH is lower than Gly-LDH. Gly-LDH displayed a selectivity order of Se(VI)<Cr(VI)<<<As(V) for the oxyanions. The enormous adsorption capacity of 731.6mgg−1 for As(V) and very high distribution coefficients (Kd) of 5.98×107mLg−1, using a V/m ratio of 2000mLg−1, were observed, which are among the highest values reported for As(V) adsorbents. The adsorption kinetic curves for As(V) fitted well with the pseudo-second order model, suggesting a chemical adsorption mechanism via As(V)NH3+ bonding. For the As(V) (at 40mgL−1 concentration), the adsorption is exceptionally rapid, showing a 93.5% removal within 30min, 98.0% removal within 40min, and ∼100% removal within 70min.

Synthesis of nanosized LDHs by Au colloidal nanoparticles as nuclei and its application for electroanalysis

Nanosized Ni–Al LDHs were synthesized via a hydrothermal method by using Au colloidal nanoparticles as nuclei for LDH growth, designated as Au/Ni–Al LDHs. Transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy were used to characterize the structure and morphology. N2 physisorption was performed to measure the specific surface area. Electrochemical impedance spectroscopy and cyclic voltammetry were introduced to investigate the electrochemical properties of Au/Ni–Al LDHs. The average size of Au/Ni–Al LDHs was small as 10±0.2nm, and the high BET surface area was obtained. The conductivity was improved as Au/Ni–Al LDHs modified glassy carbon electrode (GCE), compared to Ni–Al LDHs modified GCE. Ascorbic acid was used as a model molecule to study the electroanalytical properties of Au/Ni–Al LDHs modified GCE. The results exhibited that high sensitive detection was obtained.

Improvement of Charge Transfer Resistitance of Cathode in Ni-MH Batteries Using Ni/Al-LDH Prepared By Liquid Phase Deposition Method

Much attention has been paid to the layered double hydroxides containing transition-metal elements for various electrochemical devices. Nickel-aluminum layered double hydroxide (Ni-Al LDH) is the promising materials for the positive electrode of Ni-MH battery because of its good electrochemical properties and high stability in strong alkaline keeping the structure of α-Ni(OH)2. Furthermore, α-Ni(OH)2 have higher capacity than β-Ni(OH)2 which is commonly used for the electrode materials of Ni-MH battery, but less stability in strong alkaline. Generally, electrode is prepared by painting colloidal active materials, however, the internal resistance in the electrode is high. Improvement of the adhesion between current collector and active materials contribute to reduce the internal resistance, especially charge transfer resistance (R ct) of an electrode reaction. Previously, we reported the precipitation of Ni-Al LDH with high crystallinity and high purity by the liquid phase deposition (LPD) method. The LPD method is the syntheses method of metal oxides and hydroxides using the hydrolysis reaction of metal fluorine complexes. The merits of LPD method are easy operation and following capability for substrate surface shape. In this study, the Ni-Al LDHs were directly prepared on the surface of Ni foam as a current collector of Ni-MH battery, and investigated the reduction effect of the R ct. From the cross-sectional SEM images of the sample, dense Ni-Al LDH was deposited on the Ni foam surface, and the thickness was up to 950 nm. The resistance of charge transfer, R ct was measured by an ac impedance spectroscopy at 0.5 V vs Hg/HgO. The apparent activation energy of chage transfer is calculated from Arrhenius plots of the temperature dependence of R ct values. The composition of LDH was determinded by ICP-AES spectroscopy for Ni and Al, and neutralization titration for OH, as Ni0.95Al0.05(OH)2·A 0.05 ,where A is exchangable anionic species. Deposition of Ni-Al LDH on the surface of Ni foam directly reduced the R ct because of the improving the adhesion between current collectors and active materials as shown in Figure 1. In this case of using the sample where the Ni/Al LDH layer is deposited, the value of R ct decreased with the thickness of LDH layer on the Ni metal form from ca. 0.8 to 0.2 Ω cm-2, where those values for the sample using LDH power increase over 0.8 Ω cm-2. Furthermore, the activation energy for the electrode reaction decreased from 22.3 to 17.9 kJ mol-1 . It is suggested that the ionic transport becomes easily in the LDH layer and are coupled electronic conduction from Ni form using deposited Ni/Al LDH on Ni form. This Ni-Al LDH/ Ni foam composite will be able to provide a secondary battery electrode having high charge transfer efficiency. Figure 1

Synthesis and Application of Layered Double Hydroxide for the removal of Copper in Wastewater

Ni-Al Layered double hydroxide (Ni-Al LDHs) with M&lt;sup&gt;2+&lt;/sup&gt;: M&lt;sup&gt;3+&lt;/sup&gt; (4:1) ratio was synthesized by co-precipitation method from nitrate salt solutions. The layered double hydroxide was characterized by Fourier transform infrared spectroscopy, X-Ray Diffraction, Energy Dispersive Spectroscopy/Scanning Electronic Microscopy. The influences of phase contact time, temperature and initial concentrations were investigated to optimize the conditions for maximum adsorption. The experimental data were analyzed by Langmuir and Freundlich isotherm models and fitted well with correlation coefficient values of 0.9996 and 0.9995 respectively. The thermodynamic parameters of Isosteric heat of adsorption (DH&lt;sub&gt;x&lt;/sub&gt;), Activation energy (E&lt;sub&gt;a&lt;/sub&gt;), Enthalpy change (DH&lt;sup&gt;o&lt;/sup&gt;) and Entropy change (DS&lt;sup&gt;o&lt;/sup&gt;) were calculated to be 18.1KJ/mol, 1.447KJ/mol, -7.135J/mol and 24J/molK respectively. The results shows that the adsorption process was spontaneous and exothermic.

Enhanced performance of nickel–aluminum layered double hydroxide nanosheets/carbon nanotubes composite for supercapacitor and asymmetric capacitor

Binary composite consisting of nickel aluminum-layered double hydroxides (LDHs) nanosheets and carbon nanotubes (CNTs) is fabricated by a solution method. The CNTs are pre-coated by γ-Al2O3. The structural characterization and morphological observation demonstrate that Ni–Al hydroxide crystals with hydrotalcite structure are in situ deposited on the surface of CNTs. The as-prepared binary composite combines the pseudo-capacitive of Ni–Al LDHs with double-layer capacitive of carbon nanotubes. CNTs can improve the electrical conductivity and decrease the electrochemical polarization of the composite. Electrochemical measurements of the Ni–Al LDHs/CNTs material show a much better electrochemical performance than pure Ni–Al LDHs. It can yield a high specific capacitance of 1500Fg−1 at 1Ag−1, with 70.3% retention at 10Ag−1 in 2M KOH and a good cycling stability. An asymmetric capacitor is assembled with Ni–Al LDHs/CNTs as a positive electrode and activated carbon as the negative electrode. It can cycle reversibly in a potential window of 1.8V, and exhibits a high specific capacitance of 115Fg−1 and a high energy density of 52Whkg−1 at 1Ag−1 as well as an excellent cycling stability.

A nonenzymatic reduced glutathione sensor based on Ni–Al LDHs/MWCNTs composites

In this work, a nonenzymatic reduced glutathione (GSH) sensor was constructed based on the electrodepoition of Ni–Al layered double hydroxides (Ni–Al LDHs) on multiwall carbon nanotubes (MWCNTs) modified glassy carbon electrode (GCE). The morphologies and compositions of Ni–Al LDHs/MWCNTs nanocomposite were investigated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Cyclic voltammetry and amperometry were employed to explore the electrochemical properties and performance of Ni–Al LDHs/MWCNTs nanocomposites in sensing and detection. The results indicated that the response current of GSH oxidation at the Ni–Al LDHs/MWCNTs/GCE was obviously higher than that at the MWCNTs/GCE or the Ni–Al LDHs/GCE. The amperometric current of the sensor is proportional to the concentration of GSH in a linear range of 1.2 to 1630.0 μM with a detection limit of 0.7 μM at a signal-to-noise ratio of 3. In addition, the sensor exhibits easy preparation, low cost, good stability and anti-interference.

Anion-exchange properties of nickel–aluminum layered double hydroxide prepared by liquid phase deposition

The optimum coordination structure of Ni–fluoro complexes for the preparation of Ni–Al LDH by LPD process and the diverse anion-exchange properties of as-deposited Ni–Al on α-alumina powder were quantitatively evaluated for the industrial application of new positive material for alkali secondary batteries. The [NiF6−x−y(NH3)x(OH−)y]n+ was more suitable than [NiF6]4− as the precursor of the deposition of Ni–Al LDH in the LPD reaction, and the improved LPD reaction achieved the synthesis of high purity and high crystallinity Ni–Al LDH. All anion-exchanged Ni–Al LDHs for OH−–, Cl−–, SO42−–, and CH3COO−–forms kept the high crystallinity and showed the enlargement of interlayer distances. The tilting angle of the intercalated CH3COO− anions was about 15°. Anion-exchange capacity remained constant at a minimum of 0.8 meq g−1 in pH >10, increased as pH decreased, and reached a maximum of 8 meq g−1 at pH 2. Anion-exchange of OH−–form of Ni–Al LDH was accelerated by the neutralization of hydroxide ions in interlayers, in addition, the anion-exchange capacity and the crystallinity of Ni–Al LDH could be controlled by the amount of doped aluminum ions.

Non-enzymatic acetylcholine sensor based on Ni–Al layered double hydroxides/ordered mesoporous carbon

In this work, a novel non-enzymatic acetylcholine (ACh) sensor was constructed based on electrodepoition of Ni–Al layered double hydroxides (Ni–Al LDHs) on ordered mesoporous carbon (OMC) modified glassy carbon (GC) electrode. The obtained Ni–Al LDHs/OMC nanocomposite was characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and electrochemical methods. A novel non-enzymatic acetylcholine (ACh) sensor based on Ni–Al LDHs/OMC was developed. Compared with the pristine OMC and Ni–Al LDHs modified electrodes, Ni–Al LDHs/OMC displayed higher electrocatalytic activity toward ACh and gave a wide concentration interval of 2–4922μM and a low limit of detection (42nM, R=0.999), which is better than some reports in the literatures. The sensor also exhibited long-term stability and remarkable antifouling property. The excellent electrocatalysis for ACh can be attributed to the combination of the unique properties of Ni–Al LDHs nanoparticles and the ordered mesostructure of OMCs matrix.

Synthesis of self-assembled layered double hydroxides/carbon composites by in situ solvothermal method and their application in capacitors

Nickel–aluminum layered double hydroxides/carbon (Ni–Al LDHs/C) composites have been successfully fabricated via a facile in situ water–ethanol system. LDHs nanosheets could highly disperse on the surface of colloidal carbonaceous spheres through the interfacial electrostatic force. Ni–Al LDHs/C composite electrode prepared at 50% ethanol system exhibits the highest capacitance of 1064Fg−1 at a current of 2.5Ag−1, leading to a significant improvement in relation to each individual counterpart (3.5 and 463Fg−1 for carbon and Ni–Al LDHs at 2.5Ag−1, respectively). And a possible mechanism was proposed for the formation of the composites.

Hydroxide ion conduction in Ni–Al layered double hydroxide

Ionic conductivities of Ni/Al layered double hydroxides (Ni–Al LDHs) intercalated with CO32-, Cl− and OH− were evaluated in the temperature range of 25–80°C under 65–95% relative humidity. X-ray diffraction and Fourier transform infrared measurements confirmed the formation of Ni–Al LDHs intercalated with CO32-, Cl− and OH−. In the AC conductivity measurements, Ni–Al LDH intercalated with CO32- (Ni–Al CO32- LDH) showed the highest ionic conductivity among them. The ionic conductivity of Ni–Al CO32- LDH was 1.3×10−2Scm−1 at 80°C under 80% relative humidity. The electromotive force for the water vapor concentration cell using Ni–Al CO32- LDH showed similar behavior with that using anion exchange membrane, indicating that Ni–Al CO32- LDH is a hydroxide ion conductor. Pelletized Ni–Al CO32- LDH was confirmed to work as the electrolyte of alkaline-type direct ethanol fuel cell.

Characterization of Polystyrene (PS)/Organomodified Layered Double Hydroxide (OLDH) Nanocomposites Prepared by &lt;i&gt;In Situ&lt;/i&gt; Polymerization

PS/LDH nanocomposites were synthesized via in-situ polymerization technique using styrene monomer with toluene as a solvent. A series of LDHs (Mg-Al, Co-Al, Ni-Al, Cu-Al, Cu-Fe and Cu-Cr LDHs) was first prepared from their nitrate salts by co-precipitation method. The above prepared, pristine LDHs were organically modified using sodium dodecyl sulfate (SDS) to obtain organomodified LDHs (OLDH). Then, PS nanocomposites containing 5 wt.% OLDHs were prepared by in-situ polymerization method. The structural and thermal properties of LDHs and corresponding nanocomposites were characterized by X-Ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA). The absence of OLDH peak (003) in the XRD patterns of PS/OLDH nanocomposite confirms the formation of exfoliated nanocomposites. The presence of sulfate groups in the modified LDHs is confirmed by FTIR analysis. The appearance of new peaks in the FTIR spectra in the region of 3400-3500 cm-1, 1670-1680 cm-1and 1200-1260 cm-1for O-H stretching, H-O-H vibration and stretching vibration of sulfate, respectively indicate the existence of LDHs in the PS/OLDH nanocomposites. The entire exfoliated PS/OLDH nanocomposites exhibit enhanced thermal stability relative to the pure PS. When 50% weight loss is selected as point of comparison, the decomposition temperature of nanocomposites is about 3-5oC higher than that of pure PS.