Change In Activation Energy Research Articles

A quantum chemistry study of the deoxidation of lignite during hydrothermal dewatering treatment

ABSTRACT To investigate the deoxidation mechanism of lignite under hydrothermal dewatering (HTD) condition, the removal mechanism of carboxyl and methoxy groups was calculated at the B3LYP-D3/6-311 G(d,p) level by using density functional theory. The feasibility of deoxidation was analyzed from the perspective of thermodynamics and kinetics, and the influences of hydrogen bond on the deoxidation process were analyzed. The results showed that the activation energy of decarboxylation was lower than that of demethoxide, indicating that the carboxyl group had high reactivity. Through the hydrogen bonding between the carboxyl group and water, the activation energy of indirect decarboxylation (lignite-C6H5-COOH→lignite-C6H6-COO→lignite-C6H6+ CO2) decreased by 10 kJ/mol, whereas the activation energy of direct decarboxylation increased by 8 kJ/mol. The activation energy of demethylation was reduced by 25 kJ/mol, and the change in activation energy of subsequent decarbonylation was similar to that of decarboxylation. The two-step elementary reaction benefitted the deoxidation reaction.

Single‐Stage Optimized Microwave‐Induced Activated Carbon from Coconut Shell for Cadmium Adsorption

AbstractThe toxicity of heavy metals motivated the synthesis of coconut shell‐based activated carbon (CSAC) through single‐stage microwave irradiation technique to scavenge cadmium ions (Cd(II)). Response surface methodology revealed the optimum radiation power and radiation time which translated into 85.45 % of Cd(II) removal and 41.78 % of CSAC's yield. Isotherm and kinetic data were best described by Freundlich and pseudo‐first‐order (PFO) models, respectively. The changes of enthalpy, entropy, and activation energy were determined as well as the reduction of CSAC yield and Cd(II) removal after six regeneration cycles.

Mechanistic study of chemical looping reactions between solid carbon fuels and CuO

Copper (Cu) based chemical-looping combustion (CLC) is a promising process that utilizes solid carbon fuel such as coal and biomass. Understanding the reaction kinetics in this process can facilitate the industrial design of CLC units. In this work, molecular dynamics (MD) simulations were performed to investigate the reaction kinetics of n-butane and two simplified solid carbon fuels (lignite and anthracite) with/without copper oxide (CuO) nanoparticle. In addition, experiments were conducted on the thermal characteristics, flammability, and flame speeds of CuO and solid carbon mixtures.For n-butane, oxidation on the CuO surface is the primary reaction since the activation energy of the surface reaction is much lower than that of oxygen (O2) combustion (9.2 vs. 53.3 kcal/mol). On the other hand, for lignite, there is a smaller difference in the activation energy of O2 combustion and surface reaction (23.04 vs. 6.34 kcal/mol). We hypothesize that some solid carbon fuels can have different reaction kinetics dependent upon temperature. This is proven by the case of a simplified anthracite coal: an Arrhenius plot shows that this solid carbon fuel has two different reaction kinetic regimes and the critical temperature for the change in kinetics is related to the oxygen uncoupling of the CuO nanoparticle. Like the modeling simulations, a change in activation energy is observed in the experimental results, where desorption of molecular oxygen from CuO becomes important.

Catalytic pyrolysis of chicken manure over various catalysts

In this study, non-catalytic and catalytic pyrolysis of chicken manure (CM) were investigated to understand the pyrolysis kinetics and product distribution of CM by thermogravimetric analysis (TGA) and pyrolyzer-gas chromatography/mass spectrometry (Py-GC/MS). TGA and the apparent activation energy changes, calculated using the Ozawa method, indicated that the decomposition of CM was comprised of four reaction stages. The 1st decomposition of CM was likely the decomposition of carbohydrates and lipids, followed by the 2nd decomposition of lignin at high temperatures. The 3rd decomposition was likely involving the decomposition of proteins. At the final stage, metal carbonates in the ash of CM were likely decomposed. Py-GC/MS analysis indicated a decrease in oxygenates, such as furfural, phenol, and fatty acid, after applying acid catalysts. Among the various acid catalysts, HZSM-5(Silica/Alumina = 30), having the strongest acid sites, showed the highest efficiency for the production of aromatic hydrocarbons, followed by HBeta(Silica/Alumina = 25), HY(Silica/Alumina = 30), natural zeolite, spent fluid catalytic cracking catalyst (FCC), and bentonite. Although bentonite and spent FCC were ineffective, natural zeolite showed a catalytic effect on converting oxygenates to aromatic hydrocarbons. On the other hand, the content of a high molecular weight nitrile, hexadecanenitrile, was also increased. Commercial zeolites, HY(Silica/Alumina = 30), HBeta(Silica/Alumina = 25), and HZSM-5(Silica/Alumina = 30), led to higher aromatic formation efficiencies with less hexadecanenitrile formation than other catalysts. These efficiencies were increased significantly by varying the catalyst to CM ratio from 1/1 to 5/1, with a noticeable decrease in hexadecanenitrile.

Functionalization of poly(butylene adipate‐co‐terephthalate) with itaconic anhydride through graft copolymerization

AbstractPoly(butylene adipate‐co‐terephthalate) (PBAT) was functionalised with itaconic anhydride (IA) via melt grafting in a batch mixer, initiated by dicumyl peroxide (DCP). It was found that the ratio of IA to DCP is critical to avoid undesired side reactions, such as crosslinking and chain scission. PBAT and other polyesters with low aliphatic hydrocarbon content are relatively unreactive toward radical graft modification, providing relatively low degree of grafting. Using 2 wt% IA and 1.2 wt% DCP gave the highest degree of grafting (1%), with little indication of crosslinking or chain scission. The complex reaction mechanism of grafting presents a clear competition between grafting, homopolymerization, crosslinking, and chain scission. Using non‐isothermal kinetic modeling, it was shown that the reaction is not first order, and that models making this assumption leads to incorrect results. Using the Vyazovkin model‐free method, the effective rate constant was predicted over a typical melt processing temperature range. Low reagent concentration resulted in the lowest effective rate constant, and it was shown that the activation energy changes with conversion and is also affected by reagent concentration.

An investigation on pyrolysis of textile wastes: Kinetics, thermodynamics, in-situ monitoring of evolved gasses and analysis of the char residue

Recycling the ever-increasing industrial waste has become a pressing concern globally and pyrolysis is regarded as one of the up-and-coming techniques to recover the energy and chemical content of organic wastes. The pyrolysis of a representative industrial waste as textile waste was investigated within the scope of this study. In this way, efficient thermochemical conversion processes may be designed and optimized by creating value-added products. Different heating rates were applied to determine pyrolysis behavior using a thermogravimetric analyzer (TGA) coupled with a mass spectrometer (MS) and a Fourier transform infrared spectrometer (FT-IR). According to the obtained thermograms, the active pyrolysis region was selected for studying the kinetics, various iso-conversional methods (Friedmann, Kissinger-Akahira-Sunose; Flynn-Wall-Ozawa and Starink) were applied to the non-isothermal TG data, and the results were compared among themselves. The mean activation energy was 186.7, 185.8, 185.1, and 185.5 kJ/mol for the Friedmann, Flynn-Wall-Ozawa, Kissinger-Akahira-Sunose, and Starink models, respectively. The activation energy variation was found in good agreement among different kinetic models. The activation energy changes that were found provided a representation of the process kinetics which were described by multiple reaction schemes. All four kinetic methods were found to be applicable to forecasting the non-isothermal pyrolysis of textile wastes, although the existence of small variations in the activation energy values. Furthermore, thermodynamic parameters as enthalpy, Gibbs free energy, and entropy changes were estimated.The gasses that evolved during pyrolysis were identified by simultaneous monitoring of MS and FT-IR spectra and the temperature-dependent alteration of main volatile products were obtained. Moreover, the char residue was analyzed via ex-situ SEM-EDX and FT-IR.

Investigation of DSC curing kinetic model fitting and rheological behavior of urushiol/IPDI system

The curing behavior of urushiol/IPDI system was monitored by differential scanning calorimetry (DSC) and dynamic rheology. The change of activation energy during curing process was calculated by KAS, OFW and Friedman isoconversional methods. The relationship between curing reaction rate and temperature and curing degree was described by the piecewise fitting method. The results of model fitting and model-free fitting showed that the kinetic mechanism of the reaction changed from autocatalytic mechanism a<0.86 to n-order reaction mechanism a>0.86. The curing process of urushiol/IPDI was fitted by piecewise model, which was in good agreement with the experimental results. The piecewise model can accurately describe the curing process. The isothermal rheological test of urushiol/IPDI system was carried out. The results showed that the gelation time shortened with increasing temperature.

The Influence of Cr-Additives on the Polarization Resistance of Praseodymium-Doped Ceria Cathodes for Solid Oxide Fuel Cells

While Cr poisoning of the oxygen reduction reaction (ORR) at SOFC cathodes is widely agreed to involve deactivation of oxygen exchange sites, the degradation mechanism remains ambiguous. Here, we selected an alternative cathode material Pr0.1Ce0.9O2− free of Sr segregation, to systematically investigate the effect of Cr-induced degradation in ORR. We expand on our previous studies in which the acidity/basicity of binary additives was found to be a strong indicator of the rate of oxygen surface exchange, by electrochemically investigating the ORR activity of the PCO cathode by impedance spectroscopy. Serial infiltration with acidic Cr-based oxides was found to degrade ORR activity as reflected in a 20-fold increase in area specific resistance (ASR) without corresponding changes in activation energy, with the opposite trend obtained with Ca-based oxides. Detected changes in total capacitance, attributed to changes in surface capacitance, also suggest depressed/enhanced PCO surface redox behavior with Cr/Ca-based infiltrants. Taken together, these results point to a more universal source of ORR poisoning/activation, based on acidity/basicity, rather than physical blocking of active sites. With this improved understanding, one can expect progress to be made in the coming years in optimizing means for protecting catalytic surfaces from degradation and/or improving their performance.

Rheological and Thermal Conductivity Study of Two-Dimensional Molybdenum Disulfide-Based Ethylene Glycol Nanofluids for Heat Transfer Applications

The rheological behavior of two-dimensional (2D) MoS2-based ethylene glycol (EG) nanofluids (NFs) was investigated at low volume concentrations (0.005%, 0.0075%, and 0.01%) in a wide temperature range of 0–70 °C and at atmospheric pressure. A conventional two-step method was followed to prepare NFs at desired volume concentrations. Based on the control rotational (0.1–1000 s−1 shear rate) and oscillation (0.01–1000% strain) methods, the viscoelastic flow curves and thixotropic (3ITT (three interval thixotropic) and hysteresis loop) characteristics of NFs were examined. Shear flow behavior revealed a remarkable reduction (1.3~14.7%) in apparent dynamic viscosity, which showed concentration and temperature dependency. Such remarkable viscosity results were assigned to the change in activation energy of the ethylene glycol with the addition of MoS2. However, the nanofluids exhibited Newtonian behavior at all temperatures for concentrations below 0.01% between 10 and 1000 s−1. On the other hand, strain sweep (@1Hz) indicated the viscoelastic nature of NFs with yielding, which varied with concentration and temperature. Besides, 3ITT and hysteresis loop analysis was evident of non-thixotropic behavior of NFs. Among all tested concentrations, 0.005% outperformed at almost all targeted temperatures. At the same time, ~11% improvement in thermal conductivity can be considered advantageous on top of the improved rheological properties. In addition, viscosity enhancement and reduction mechanisms were also discussed.

Manipulating Electrocatalytic Polysulfide Redox Kinetics by 1D Core–Shell Like Composite for Lithium–Sulfur Batteries

AbstractAlthough lithium–sulfur batteries have high theoretical energy density of 2600 Wh kg−1, the sluggish redox kinetics of soluble liquid polysulfide intermediates during discharge and charge is one of the main reasons for their limited battery performance. Designing highly efficient electrocatalysts with a core–shell like structure for accelerating polysulfide conversion is vital for the development of Li–S batteries. Herein, core–shell MoSe2@C nanorods are proposed to manipulate electrocatalytic polysulfide redox kinetics, thereby improving the Li–S battery performance. The 1D MoSe2@C is synthesized via a facile hydrothermal and subsequent selenization reaction. The electrocatalysis of MoSe2 is confirmed by the analysis of symmetric batteries, Tafel curves, changes of activation energy, and lithium‐ion diffusion. Density functional theory calculations also prove the low Gibbs free energy of the reaction pathway and the lithium‐ion diffusion barrier. Therefore, the Li–S batteries using MoSe2 electrocatalyst exhibit an excellent rate performance of 560 mAh g−1 at 1 C with a high sulfur loading of 3.4 mg cm−2 and an areal capacity of 4.7 mAh cm−2 at a high sulfur loading of 4.7 mg cm−2 under lean electrolyte conditions. This work provides a deeper insight into regulation of polysulfide redox kinetics in electrocatalysts for Li–S batteries.

Technical note: Temperature and concentration dependence of water diffusion in polyvinylpyrrolidone solutions.

ObjectiveThe goal of this work is to provide temperature and concentration calibration of water diffusivity in polyvinylpyrrolidone (PVP) solutions used in phantoms to assess system bias and linearity in apparent diffusion coefficient (ADC) measurements.MethodADC measurements were performed for 40 kDa (K40) PVP of six concentrations (0%, 10%, 20%, 30%, 40%, and 50% by weight) at three temperatures (19.5°C, 22.5°C, and 26.4°C), with internal phantom temperature monitored by optical thermometer (±0.2°C). To achieve ADC measurement and fit accuracy of better than 0.5%, three orthogonal diffusion gradients were calibrated using known water diffusivity at 0°C and system gradient nonlinearity maps. Noise‐floor fit bias was also controlled by limiting the maximum b‐value used for ADC calculation of each sample. The ADC temperature dependence was modeled by Arrhenius functions of each PVP concentration. The concentration dependence was modeled by quadratic function for ADC normalized by the theoretical water diffusion values. Calibration coefficients were obtained from linear regression model fits.ResultsMeasured phantom ADC values increased with temperature and decreasing PVP concentration, [PVP]. The derived Arrhenius model parameters for [PVP] between 0% and 50%, are reported and can be used for K40 ADC temperature calibration with absolute ADC error within ±0.016 μm2/ms. Arrhenius model fit parameters normalized to water value scaled with [PVP] between 10% and 40%, and proportional change in activation energy increased faster than collision frequency. ADC normalization by water diffusivity, D W, from the Speedy–Angell relation accounted for the bulk of temperature dependence (±0.035 μm2/ms) and yielded quadratic calibration for ADCPVP/D W = (12.5 ± 0.7) ·10−5·[PVP]2 − (23.2 ± 0.3)·10−3·[PVP]+1, nearly independent of PVP molecular weight and temperature.ConclusionThe study provides ground‐truth ADC values for K40 PVP solutions commonly used in diffusion phantoms for scanning at ambient room temperature. The described procedures and the reported calibration can be used for quality control and standardization of measured ADC values of PVP at different concentrations and temperatures.

Kinetic and thermodynamic analyses for pyrolysis of hemp hurds using discrete distributed activation energy model

In many counties, hemp is becoming a high-valued economic crop. Post-processing, more than 65% w/w of its starting material becomes waste. Herein, pyrolysis of hemp hurds/residues was investigated under low (10–50 °C/min) and intermediate (100–150 °C/min) heating rates using a discrete distributed activation energy model (DAEM). Thermochemical decomposition of hemp hurds occurred in three stages: drying, active pyrolysis, and char formation, accounting for 70–80% w/w overall weight loss. With the discrete DAEM, the model can be utilized for predicting pyrolysis behaviors of hemp hurds accurately with correlation coefficient of over 0.99. Different reaction mechanisms appeared between the low and intermediate heating rates with 60 and 25 parallel first-order pyrolytic reactions detected, respectively. Under low heating rates, the pyrolysis showed high reactivity. The activation energy (E) and enthalpy change (ΔH) varied within 240–320 kJ/mol. The Gibbs free energy (ΔG) was 120–200 kJ/mol. The entropy change (ΔS) was 120–300 J/mol∙K. Under intermediate heating rates, the reactions were close to thermodynamic equilibrium and stability. The E and ΔH fluctuated from 80 to 250 kJ/mol. The ΔG was within 160–200 kJ/mol. The ΔS was between −100 and 100 J/mol∙K.

Evaluating performance of pyrolysis and gasification processes of agriculture residues-derived hydrochar: Effect of hydrothermal carbonization

In this study, corn straw and rice husk were hydrothermally carbonized at 180 °C and 240 °C. The effect of hydrothermal carbonization on the biomass/hydrochar characteristics, fate of heavy metals such as As, Cr, Pb, Ti, Cd, Zn, Fe, Cu, and Ni, global reactivity of the pyrolysis and gasification of biomass and hydrochar were investigated in a thermogravimetric analyzer, followed by kinetic modeling and reactivity prediction. Results showed that hydrothermal carbonization temperature 180 °C is more suitable for producing solid fuel in terms of low heavy metals content. Higher hydrothermal carbonization temperature (240 °C) decreased O/C content and improved various characteristics of the hydrochar such as coalification degree, carbon content, higher heating value and the specific surface area. While hydrothermal carbonization conducted at lower temperature of 180 °C, was advantageous for obtaining higher energy yield efficiency and hydrochar yield. The gasification reactivity of hydrochar was more sensitive to the heating rate than the pyrolysis process. The activation energy (Ea) of the pyrolysis process varied significantly with conversion, whereas the gasification activation energy changes were insignificant. Based on the reactivity prediction, the hydrothermal carbonization effect on corn straw and rice husk was almost similar. The hydrochar generated under severe hydrothermal carbonization temperature (240 °C) showed higher thermal stability during pyrolysis in comparison with gasification. Compared with the gasification of rice husk hydrochar, hydrochar gasification of corn straw had lower Ea, hence requires less energy to produce syngas. The results of this research imply that biomass hydrochar is a suitable alternative option to produce pulverized solid fuel.

Effect of gallic acid and chlorogenic acid on physicochemical, microstructural and thermal degradation properties of ready-to-eat sea cucumber

To enhance thermal stability of ready-to-eat sea cucumbers (RSC), gallic acid (GA) and chlorogenic acid (CA) were employed. Physicochemical and microstructural properties of RSC were evaluated. When RSC were treated by 12 mg/mL of GA and 10 mg/mL of CA, ε-amino group level decreased by 50.2% and 47.9%, and the hardness increased by 74.8% and 80.0%, respectively. The proportion of free water decreased by 10.9% and 8.8%, and the relaxation time decreased by 52.9 and 57.8 ms, respectively. In addition, aggregation and density of collagen fibers increased and their porosity decreased, observed by Van Gieson's staining and scanning electron microscope images. After crosslinked by 12 mg/mL GA and 10 mg/mL CA, the peak temperatures increased to 137.5 °C and 130.0 °C similar to changes of activation energy, indicating that the thermal stability of RSC was improved. It can provide a theoretical basis for prolonging the storage life of RSC.

Carbon Dioxide Mediated Cellulose Dissolution and Derivatization to Cellulose Carbonates in a Low-pressure System

An effective switchable solvent system using carbon dioxide (CO2) and 2-tert-butyl-1,1,3,3-tetramethylguanidine (BTMG) for cellulose dissolution and derivatization was developed. High concentration cellulose solution (up to 10 wt%) could be achieved by dissolving microcrystalline cellulose rapidly, within 5 min, into DMSO in presence of BTMG and 1 atm CO2 at room temperature. The cellulose-carbonate anion intermediate was characterized by 1H and 13C NMR spectroscopies, emphasizing the generation of cellulose carbonate anions and protonated BTMG. Addition of organochlorides into the cellulose solution triggers a nucleophilic substitution with cellulose-carbonate anions, producing various cellulose benzyl carbonates and a cellulose-carbonate-ester with degree of substitution (DS) up to 1.83 at 1 atm CO2 pressure and room temperature. The activation energy (Ea) and Gibbs free energy change (ΔG) of CO2-mediated dissolution and nucleophilic substitution were calculated by density functional theory. The results showed that the nucleophilic substitution is the rate-limiting step.

Modeling of a cyclic sorption–desorption unit for continuous high temperature CO2 capture from flue gas

This study focuses on the modeling of a sorptive unit for CO2 capture at high temperatures, considering as case-study the data obtained from experiments using a conventional post-combustion stream from coal power plants: 15% CO2/85% N2 at 623 K and 134 kPa. A one-dimensional (1D) heterogeneous dynamic fixed-bed model able to predict the CO2 equilibrium and kinetics of adsorption on a K-promoted hydrotalcite was successfully developed and implemented in gPROMS® software. The bi-Langmuir model was chosen to describe the experimental equilibrium data, as it considers the two different adsorption sites on the K-promoted hydrotalcite. A loss of capacity was observed after the first cycle performed in dry conditions. An Elovich-type expression, accounting for the change in activation energy of adsorption and desorption for each site as a function of the surface coverage, was also introduced in the model. The two sites model was used and an excellent fit to the breakthrough curves of CO2 adsorption/desorption and temperature histories was obtained. In order to make the model more robust, it was additionally validated at 573 K, for a total pressure range between 134 and 200 kPa, in wet conditions. The model validation represents an important advance, since it will allow processes optimization, and consequently the industrial design.

Kocks-Mecking-Estrin type model for high-temperature creep of Zircaloy-4

Results of known detailed microstructural studies of the Zircaloy-4 at various creep stages were used to validate the conventional microstructure-based MKE approach, modeling the kinetics of the production and recombination of dislocations. The developed model is considered a tool to interpret the governing mechanisms of deformation. The strain rate in non-stationary dislocation structures was determined by the mobility of dislocations in an external stress field, lowered by the back-stress imposed dislocation structure. The rate of microstructure recovery determines the steady-state regime's strain rate. As the root of power-law creep is still a disputable issue, microstructure recovery is analyzed in the view of conservative and non-conservative climb processes. It is shown that at least in materials where dipole instability is observed, the conservative climb may cause a change in activation energy and power-law exponent value close to the fifth power law.

Revised equation of enzymatic kinetics and thermodynamic mechanisms for directed evolution of enzymes

AbstractThe equation of enzymatic kinetics is revised, and thermodynamic mechanisms of directed evolution of enzymes are proposed based on both that and the thermodynamic model of enzyme action. In theory, there are two mechanisms of enzymes to improve its catalysis efficiency in directed evolution. The first refers to the change of activation energy of enzymatic reactions. The modulation of structural compatibility between enzyme and substrate serves as the second mechanism and the major motivation for enzymes to enhance their catalysis in situations of directed evolution.

Influence of sugarcane bagasse addition in co-pyrolysis with sewage sludge on the thermogravimetric characteristics and study of kinetic

To evaluate the influence of sugarcane bagasse in co-pyrolysis with sewage sludge, thermogravimetric analysis (TGA) in the presence of argon was studied. Pyrolysis experiments were carried out for sewage sludge (SS), sugarcane bagasse (SCB), and SS/SCB mixtures (1:1 mass ratio) in the temperature range of 30–800 °C at a heating rate of 10 °C per minute. Kinetic analysis was determined by using the Arrhenius equation and showed a change in activation energy, i.e., 27–52 kJ/mol, 29–46 kJ/mol, and 20–32 kJ/mol in the three stages of temperature ranges for SS, SCB and those for SS/SCB mixtures, respectively. The behavior of material degradation is attributed to this variation of activation energy. In contrast to pyrolysis of only-SS, co-pyrolysis mixtures (SS/SCB) offer improvement in the highest rate of degradation by 55%, the shift of peak temperature to lower value by 2–13%, reduced quantity of residue left behind by 56%, and alteration in activation energy by −60 to +36% suggest a synergism upon addition of SCB in SS.

Fingerprint of semi-crystalline structure memory in the thermal and ionic conduction properties of amorphous ureasil-polyether hybrid solid electrolytes.

Correlations among the structure, thermal properties, and ionic conductivity of solid polymer electrolytes (SPEs) were studied using a ureasil–polyethylene oxide (U-PEO) organic–inorganic hybrid prepared according to a simple sol–gel route, employing a low molecular weight PEO macromer (Mw = 1900 g mol−1). The behavior of an amorphous sample loaded with lithium triflate (LiTFSI) at an optimum ratio between ether oxygen and lithium (EO/Li+ = 15) was compared with that of a semicrystalline sample prepared without salt loading. The temperature range investigated by differential scanning calorimetry (DSC), Raman spectroscopy, small angle X-ray scattering (SAXS), and complex impedance spectroscopy covered both the glass transition and the melting temperature of the U-PEO. The gauche to trans conformational transformation of the (O–C–C–O)Li+ sequence showed similarity between the temperature evolution of the semi-crystalline U-PEO and amorphous U-PEO:Li+ samples, providing an indication of the local structural memory of crystalline state in the amorphous SPE. The linear thermal expansion of the average correlation distance between the siloxane crosslink nodes and the long-distance period of the lamellar semi-crystalline edifice were determined by SAXS. Comparison of the expansion curves suggested that although the siloxane nodes were excluded from the PEO crystalline edifice, the sharp expansion of the amorphous region between the lamellae during melting permitted modulation of the free volume of the hybrid network. In addition, the temperature-induced Li+-EO decomplexation observed by Raman spectroscopy explained the change of the average activation energy of the conduction process revealed by the different Arrhenius regimes. These results evidence the key role of the ionic conductivity decoupling from the segmental motion of chain pair channels on the improvement of ion mobility through the free volume between chains. This concept may inspire materials chemistry researchers to design optimized structures of polymer electrolytes with minimized structural memory of crystaline building blocks and improved ionic conductivity.