Thickness Of SiO2 Shell Research Articles

Optimization and performance assessment of Ag@SiO2 core–shell nanofluids for spectral splitting PV/T system: Theoretical and experiment analysis

Ag@SiO2 nanofluid is widely used in spectral splitting PV/T system. Its core–shell structure has great influence on the optical properties. In this work, we focus on the comprehensive analysis and structure optimization of Ag@SiO2 nanofluid to achieve its optimal spectral performance. DDA method is used to predict the optical properties of Ag@SiO2 nanofluid and an optimization model based on filter efficiency is proposed. The effect of the SiO2 shell thickness and Ag core mass concentration is analyzed. It indicates that the spectral performance of Ag@SiO2 nanofluid can be improved with SiO2 shell thickness of 15–40 nm and Ag core mass concentration of 81–135 mg/L. To achieve the same theoretical merit function of 1.46, the usage of Ag mass can be reduced by 25/33/44/62 % with SiO2 coating of 10/20/40/70 nm. The optimal structure to achieve the highest filter efficiency η of 37.8 % is with a shell thickness of 20 nm and a mass concentration of 113.9 mg/L. An indoor PV/T operation testing is conducted to verify the optimization results. The merit function of Ag-based nanofluids increases from 1.58 to 1.598 and a reduction in Ag usage of 17 % is achieved with a SiO2 coating shell of 17.8 nm. Operation stability is also enhanced with no aggregation observed during the working cycle and 7-day static experiment.

In-situ synthesis of SiC/SiO2 nanowires by catalyst-free thermal evaporation of silicon powder and their photoluminescence properties

Core-shell structured SiC/SiO2 nanowires (SiC/SiO2 NWs) were synthesized by a simple thermal evaporation method without a catalyst. The influence of the growth temperature and holding time on the microstructure and composition of the nanowires were investigated. The results indicate that within the temperature range of 1150 to 1550 °C, the color of SiC/SiO2 nanowires gradually transitions from pure white to off-white with increasing temperature. During this process, the average diameter of SiC/SiO2 increases from ∼74 nm to ∼291 nm, while the surface SiO2 layer thickness decreases from ∼17 nm to ∼5 nm, with nanowires can reach lengths of hundreds of micrometres. Variations in supersaturation of SiO and CO at different temperatures lead to discrepancies in nanowire diameter and SiO2 shell thickness. At 1350 °C, prolonged holding time enhances silicon powder reaction, resulting in increased structural disorder of the obtained SiC/SiO2 nanowires. The nanowire growth follows a vapor-solid (VS) mechanism. Additionally, the study demonstrates that the photoluminescence (PL) characteristics of the nanowires exhibit a blue shift attributable to their nanoscale dimensions, while variations in emission spectra correlate with stacking faults, SiC diameter, and SiO2 thickness. This work may be provide a theoretical basis for preparing SiC/SiO2 nanowires with different diameters and SiO2 shell thicknesses, which is crucial for advancing the development and application of SiC/SiO2 nanoceramics.

Synthesis of ZrN–SiO2 core–shell particles by a sol–gel process and use as particle‐based structured coloring material

AbstractZrN–SiO2 core–shell particles were prepared, where the ZrN core nanoparticles and SiO2 shell were designed to exhibit localized surface plasmon resonances (LSPRs) and structural coloring. The heating of ZrO2 nanoparticles with Mg3N2 under a nitrogen gas flow produced ZrN nanoparticles with a diameter in the range of 10–20 nm. The dispersion of ZrN nanoparticles in water exhibited an absorption maximum at approximately 700 nm owing to LSPRs. An SiO2 shell was formed on the ZrN nanoparticles using a sol–gel process. Scanning transmission electron microscopy confirmed the formation of ZrN–SiO2 core–shell particles containing ZrN particles with a diameter of approximately 10 nm. The SiO2 shell thickness was controlled by varying the reaction time to form SiO2. The use of particles as a structural component of a structural color material owing to the high uniformity of the size of obtained core–shell particles was investigated. The obtained ZrN–SiO2 core–shell particles were arrayed on a glass substrate using a layer‐by‐layer method. The particle‐stacked film of the ZrN–SiO2 core–shell particles exhibited the maximum reflection depending on the particle size of the SiO2 shell.

Hollow SiO2 photonic crystal - graphene quantum dots composite and its application in multi-level intelligent anti-counterfeiting through regulation synergistic effect of structural color and fluorescence

The research on composite materials with rainbow color (structural color) and ultraviolet excitation characteristics (fluorescence) is the development direction of the new generation of functional photonic engineering materials. Herein, composite materials composed of hollow SiO2 photonic crystals (PCs) with nanometer thickness and PEGDA gel containing graphene quantum dots (GQDs) were prepared to achieve fluorescence regulation effect and thus apply in multi-level intelligent anti-counterfeiting. Due to the SiO2 shell thickness of 20–41 nm, the Bragg diffraction law explained that the material underwent secondary refraction, resulting in a wide photonic band gap (PBG). On the other hand, due to the comparison of refractive index between air (n = 1) and composite material (n = 1.46), the transmittance of the composite materials were only 21 %–26 %, indicating strong refractive ability. Therefore, we constructed a PC structure with a wide photonic bandgap (PBG) to provide better wavelength selectivity and coverage range, which would significantly increase the effect of structural color on fluorescence. Based on the unique quantum dot size effect of GQDs, we also investigated the fluorescence enhancement effect with 157 nm FWHM located on PC materials. Therefore, artificial design and control of both fluorescence enhancement and fluorescence suppression had been achieved through multi-level regulation of structural color. We further utilized these properties to create multi-level anti-counterfeiting verification patterns, such as a 3 × 3 digital encoding matrix. The authenticity of the product information must be verified through stepwise identification under specified conditions. This intelligent anti-counterfeiting technology offers a novel approach to safeguard information security.

Optimization of plasmonic nanofluid filters for spectral splitting photovoltaic/thermal systems

There remains a scarcity of studies on the utilization and optimization of core–shell plasmonic nanofluid filter although it shows potential in solar energy exploitation. To fill this research gap, this paper introduces an optimization methodology founded on merit function (MF) to optimize the Au@SiO2-based nanofluid filters for enhancing the photovoltaic/photothermal (PV/T) system performance. Initially, the MF model of the nanofluid filtered-PV/T system was constructed based on a reliable optical model and validated by referenced experimental results. Using these models, the effect of nanofluid parameters on the system performance and the mechanism of optimization procedure were investigated. Results indicated that modifying SiO2 shell thickness is a cost-effective means of tailoring the transmittance of the nanofluids compared to adjusting the Au core diameter. The optimization mechanism can be summarized as enhancing electrical efficiency or improving thermal efficiency to offset electricity losses. Furthermore, the MF of the Au@SiO2/EG nanofluid increased from 1.3737 to 1.3844 with optical thickness decreasing from 44 mm to 40 mm by mixing with Ag@SiO2 nanoparticles, indicating the cost-effectivity of blended nanofluid. The MF of the optimized blended nanofluids are 0.007–0.084 higher than those of the referenced nanofluids. This work offers a feasible pathway toward achieving high-performance nanofluid optical filters.

Magnetic Supraparticles Capable of Recording High‐Temperature Events

AbstractSuperparamagnetic iron oxide nanoparticles (SPIONs) are prone to oxidation at elevated temperatures (>300 °C) and lose their magnetizability upon transition from magnetite/maghemite (γ‐Fe2O3 / Fe3O4) to hematite (α‐Fe2O3). Silica (SiO2) shells can effectively prevent this undesired effect up to ≈1000 °C. Herein, the study shows how to utilize SPIONs with varying SiO2 shell thickness and thus, different oxidation susceptibility, and how to combine them in micrometers sized assemblies – so‐called supraparticles (SPs), to create a structurally emerging magnetic temperature recording functionality. The desired oxidation of non or weakly‐protected SPIONs within SPs upon temperature events reduces dipole–dipole interactions of well‐protected SPIONs in the confined SP entity. The resulting change of magnetic interactions therefore contains information on the thermal history of the SP, which can be spectrally read out via magnetic particle spectroscopy within seconds. Their working range can be tuned from 400 to 1000 °C on two independent structural hierarchy levels, namely the SiO2 shell thickness and the freely selectable ratios of different building blocks in the SP. The application of such SPs as particulate additives for magnetic recording of high‐temperature events, especially relevant in metal, alloy, and ceramic processing, representing a yet unexplored and optically‐independent option for bulk temperature recording is proposed.

SiO2-coated lead halide perovskites core-shell and their applications: a mini-review.

Research on lead halide perovskites has demonstrated that they are one of the potential materials for optoelectronic and bio-related applications owing to their promising optical and electronic properties. However, their poor chemical stability in ambient environments is a critical factor that affects their practical applications. Silica is known for its excellent environmental/chemical stability and good optical properties. Therefore, SiO2-coated lead halide perovskites have been studied by introducing the protective layer containing SiO2 to prevent the rapid destruction of their surface chemistry and environmental degradation. It is found that lead halide perovskite core-shell can significantly improve the stability and preserve their high photoluminescence quantum yield. In addition, controlling the shell thickness is also important to produce effective and suitable inorganic halide perovskites core-shell for practical applications. This mini-review discusses the stability, synthesis method and applications of SiO2-coated lead halide perovskite core-shell. Furthermore, the effect of the SiO2 shell thickness on lead halide perovskite core-shell-based applications is also reviewed.

Syngas production through dry reforming of ethanol over Co@SiO2 catalysts: Effect of SiO2 shell thickness

Morphology structure is regarded as one of the key factors in developing highly efficient catalysts for heterogeneous catalytic reactions. In this work, the influence of SiO2 shell thickness on the performance of the Co@SiO2 catalysts in ethanol dry reforming was studied in detail. Indeed, the different shell thickness resulted in various strengths of metal-support interactions for the Co@SiO2 catalysts, thereby greatly affecting the activity/stability. Herein, Co@SiO2–1.5 sample with ca.20 nm shell thickness exhibited better physicochemical properties. The Oads/Olatt ratio of Co@SiO2–1.5 (1.03) was higher than that of Co@SiO2–1 (0.75) and Co@SiO2–2.5 (0.91) as depicted in XPS spectra. Oads sites were indexed with the activated O species originated from O defects. On the other hand, the highest performance was obtained over Co@SiO2–1.5 sample with the optimal shell thickness as well as strong metal-support interaction. Particularly, 100% of ethanol conversion was achieved at 550 °C for Co@SiO2–1.5 catalyst and the targeted H2/CO ratio was closer to 1 compared to other samples. In addition, no obvious deactivation (ethanol conversion still be 100%) occurred after 40 h time on stream tests. This finding might depict a general strategy to design/develop the attractive catalysts with the core/shell structure for other heterogeneous reactions.

Interface modified Si@SiO2/PVDF composite dielectrics with synchronously ameliorative dielectric and mechanical properties

AbstractTo efficaciously decrease dielectric loss while still synchronously harvesting a high dielectric constant (ε′) and breakdown strength (Eb), as well as good mechanical properties in silicon (Si)/poly(vinylidene fluoride) (PVDF), in this work, the core@shell structured Si@silicon dioxide (SiO2) particles were first prepared via a high temperature oxidation, and subsequently incorporated into the PVDF to generate morphology‐dependent composites with a high‐ε′ and Eb but low loss. The SiO2 shell effects on the morphology, dielectric, and mechanical properties of PVDF composites were explored. In comparison to pristine Si/PVDF, the Si@SiO2/PVDF presents significantly suppressed loss and boosted Eb because the SiO2 interlayer not only efficiently blocks the connection between the raw Si and greatly impedes the long‐range charges migration even at high filler loadings, but also obviously improves the compatibility between Si and PVDF at the interfaces which promotes fillers' uniform dispersion in host matrix, thus leading to enhanced dielectric and mechanical properties. The fitting result by the Havriliak–Negami equation theoretically elucidates the SiO2 interlayer's suppression effect on charge migration behavior in the composites. More importantly, dielectric properties can be efficiently turned via tailoring the SiO2 shell thickness. The Si@SiO2/PVDF with simultaneously enhanced dielectric and mechanical performances shows promising uses in the electrical and microelectronics industries.

SiO2 shell thickness affects the tribological properties of Si3N4@SiO2/PEEK core–shell composite prepared by cold sintering

Silica (SiO2) coated Silicon Nitride (Si3N4) core–shell composite (Si3N4@SiO2) was prepared by Stöber method. Three SiO2 shell thicknesses (12.5 nm, 25 nm, and 50 nm) were obtained by adjusting the aqueous ammonia concentration. Polyetheretherketone (PEEK) filled Si3N4@SiO2 core–shell composite (Si3N4@SiO2/PEEK) was successfully prepared at low temperature 240 °C by cold sintering. The influence of SiO2 shell thickness on the dry tribological properties of Si3N4@SiO2/PEEK composite was studied. With SiO2 shell thickness increasing, the density of Si3N4@SiO2/PEEK composite increases, and the hardness firstly increases, then changes little. The friction coefficient and wear rate of Si3N4@SiO2/PEEK composite with SiO2 shell thickness of 50 nm decrease by 15% and 80%, respectively, comparing to that with SiO2 shell thickness of 12.5 nm.

FEM investigation of Cu@SiO2 core-shell nanoparticle for a sensitive and low-cost SERS and SEF substrate

We theoretically investigate the plasmon coupling properties of Cu@SiO2 core-shell system that supports the measurement of surface enhanced Raman spectroscopy (SERS) and surface enhanced fluorescence (SEF) technology. The roles of Cu core and SiO2 shell in tuning LSPR have been quantitatively discussed by calculating the localized electric field enhancement factor (EF), fluorescent quantum yield, SERS and SEF EF in the nanogap based on finite element simulations. In this work, we demonstrate that the SERS and SEF effect strongly depend on the core size, shell thickness and dimer distance. The larger size of Cu core, ultrathin thickness of SiO2 shell and shorter dimer distance could be considered as the ideal substrate. Meanwhile, the strong localized excitation enhancement is a vital contribution to fluorescence spectral. By comparison, it is found that the enhancement effect of the Cu, Au and Ag cores are very close in order of magnitude in the red and near infrared regions, and thus the low-cost Cu core may act as an active substrate in these regions. At the excitation wavelength of 630 nm, the optimized core size of 60 nm and shell thickness of 1 nm provide the maximum Raman and fluorescence EF as high as 9 and 4 orders of magnitude. Our theoretical results not only help understanding the underlying enhancement mechanism for the core-shell SERS and SEF effect, but also contribute to develop the low-cost and sensitive detection technology.

Enhancing energy storage property of polymer nanocomposites by rationally regulating shell thickness of core–shell structured nanoparticles

AbstractDesign of core–shell structure for ceramic filler is an effective way to improve the electric insulation property of polymer matrix. However, it still faces the disadvantage of a low dielectric constant, inhibiting the increase in energy storage density. Herein, we propose an effective strategy for regulating shell thickness to induce dielectric polarization, which simultaneously improves dielectric constant and breakdown strength of polyvinylidene difluoride (PVDF)‐based nanocomposite incorporated by core–shell structured BaTiO3@SiO2 (BT@SO) nanoparticles. The results show that BT@SO fillers with a moderate SiO2 shell thickness of 15 nm and a low content of 1.0 vol% enhances dielectric constant and breakdown strength of PVDF‐based nanocomposite to 14.7 and 500.5 MV/m, respectively. Compared with pure PVDF, the dielectric constant and breakdown strength of PVDF/BT@SO are increased by 82.2% and 61.3%, respectively. Comprehensively, its discharge energy density is enhanced by 352%, up to 12.2 J/cm3, which is attributed to the high induced polarization of charge confinement and the multi‐function combined effects of SiO2 shell as a deep trap, barrier and adsorption layer. This study provides more insight into the interface control mechanism of core–shell nanostructure, and offers a theoretical basis for designing polymer nanocomposites with high energy storage density.

Improved energy storage property in polyvinylidene fluoride‐based multilayered composite regulated by oriented carbon nanotube@SiO2 nanowires

AbstractHigh‐performance dielectric capacitors are essential components of advanced electronic and pulsed power systems for energy storage. Because of their high breakdown strength and excellent flexibility, polymer‐based capacitors are regarded as auspicious energy storage material. However, the energy storage capacity of polymer‐based capacitors is severely limited due to their low polarisation and low dielectric permittivity. The modified Stöber method was used to construct two types of CNT@SiO2 (CS) one‐dimensional core‐shell structured nanowires with different shell thicknesses. By integrating the procedures of solution mixing, melt blending, hot‐stretching orientation and hot pressing, sandwich‐structured poly (vinylidene fluoride) (PVDF)‐based composites were fabricated. The CS core‐shell nanowires dispersed in the inter‐layer serve as electron donors, leading to a high permittivity, while two PVDF outer layers provide the favourable overall breakdown strength. The insulating SiO2 shell can effectively limit the migration of carriers and keep the dielectric loss at a relatively low level in the composites. The CS/PVDF composite exhibited an enhanced discharged density (~6.1 J/cm3) and breakdown strength (~241 kV/mm) when the interlayer filled with as small as 1 wt% CS nanowires with the SiO2 shell thickness of 8 nm, which is 203% and 18.7 % higher than pure PVDF (~2.01 J/cm3 at 203 kV/mm), respectively. This research presents a practical strategy for designing and fabricating advanced polymer film capacitor energy storage devices.

Multifunctional Au@Ag@SiO2 Core–Shell–Shell Nanoparticles for Metal-Enhanced Fluorescence, Surface-Enhanced Raman Scattering, and Photocatalysis Applications

Au@Ag@SiO2 core-shell-shell nanoparticles (NPs) were prepared by a facile one-pot synthetic technique. The Au@Ag core size and SiO2 shell thicknesses are readily controlled by adjusting the precursor concentration. The multilayered NPs with dielectric SiO2 outer shells and bimetallic Au@Ag cores exhibited both the chemical stability of Au with the high scattering efficiency of Ag. Furthermore, the SiO2 shell is beneficial to the metal-enhanced fluorescence for biomedical applications. Metal-enhanced fluorescence, surface-enhanced Raman scattering, and photocatalytic activities of silica-coated Au@Ag, Ag, Au, and Au/Ag core-shell NPs were compared and discussed. The size and structure of Au@Ag@SiO2 core-shell-shell NPs were optimized to maximize their optical and catalytic activities.

Modulation of electromagnetic absorption and shielding properties of geopolymer nanocomposites by designing core–shell structure of carbon nanotubes

In this work, an electromagnetic (EM) protective building material was developed by combining silica (SiO2)-grafted carbon nanotubes (S@CNTs) with geopolymer (GeoP). The EM absorption and shielding properties of the GeoP nanocomposites were modulated by tailoring the SiO2 shell thickness. With the increase in shell thickness, the attenuation coefficient decreased, while the impedance matching degree, which acted as a prerequisite for evaluating EM absorption performance, improved. As a result, the minimum reflection loss (RLmin) reached −38.4 dB at 11.1 GHz and the effective absorption bandwidth of 3.4 GHz with a thickness of 2.9 mm was obtained. Practically, the electron transport capability was promoted with a thinner SiO2 shell, leading to an improvement in electrical conductivity. As the conductivity increased, the EM interference shielding effectiveness (SE) increased to 11.0 dB, while the RLmin also increased to −8.7 dB. Based on the underlying mechanism analysis, the strategy for modulating EM performance can be extended to other building materials.

Broadband absorption enhancement in carbon-based perovskite solar cell with a composite light trapping structure

In this work, a composite light-trapping strategy based on Ag@SiO2 nanoparticles embedded inside the active layer and an antireflection coating on the top surface is proposed to obtain broadband absorption improvement in carbon-based perovskite solar cells (C–PSCs). The effects of geometrical parameters, including the radius and period of Ag nanoparticles, the thickness of the protective SiO2 shell and the thickness of the antireflection coating, on the light absorption are investigated using the finite-difference time-domain (FDTD) method. Simulation results illustrate that nearly full absorption of light can be achieved with the optimized structure parameters for a 600 nm thick perovskite layer using the composite light-trapping scheme. The short-circuit current density (JSC) exhibits an improvement of 24.8% relatively compared to the C-PSC without light management. The proposed composite light-trapping structure allows improved light utilization and saved material consumption in C–PSCs.

Enhanced breakdown strength and restrained dielectric loss of polypropylene/maleic anhydride grafted polypropylene/core‐shell ZrO2@SiO2 nanocomposites

AbstractTo simoutinusly achieve improved breakdown strength (BDS) and suppressed dielectric loss, a modified ternary nanocomposite composed of polypropylene (PP), maleic anhydride‐grafted PP and core‐shell structure SiO2@ZrO2 nanoparticles is proposed. By tailoring the thickness of SiO2 shell from 3 to 11 nm and the nanofillers content from 0.5 to 5 wt%, the particles disparsion is improved and meanwhile both the deep trap density and the interaction force between molecules are enhanced. In consequence, the restricted transportation of electrons along molecule chains as well as between chains together raise the DC BDS, that the BDS of optimum sample film reaches 430.8 kV/mm, 23% higher than neat PP. Besides, the ternary nanocomposites with SiO2@ZrO2 less than 3 wt% maintain the tanδ below 0.3% at a broad frequency ranging from 0.1 Hz to 100 kHz, which is an extremely low level same as neat PP.

Effective regulation of upconversion luminescence in NaErF4 and NaErF4@SiO2 core-shell particles

Upconversion luminescence materials have gained extensive attentions owing to their unique luminescence characteristics of converting near-infrared excitation to visible light emission. However, how to improve the doping concentration of activator (usually <3 mol%) in traditional sensitizer-activator system is still a great challenge due to the luminescence quenching effect. In this work, NaErF4 crystals with diverse crystal phases and morphologies were prepared by simple hydrothermal method, constructing a 100% doping concentration system of activator (Er3+). With the increase of F− content, the phase of NaErF4 transfers from cubic to hexagonal, and the morphology changes from nanospheres to hexagonal microflakes, meanwhile, the upconversion luminescence intensity also increases gradually. In addition, in order to further inhibit the luminescence quenching effect of NaErF4 bare core, a series of NaErF4@SiO2 core-shell samples with different SiO2 shell thickness were successfully prepared. Compared with NaErF4 bare core, the morphology and structure of the NaErF4@SiO2 core-shell samples have no obvious change, but the UC luminescence intensity is significantly enhanced. Interestingly, the change of NaErF4 crystal phase and SiO2 shell thickness can both bring about multicolor luminescence. In addition, different from the traditional NaYF4:Yb, Er co-doping system, the as-prepared hydrophilic NaErF4 and NaErF4@SiO2 samples showed a greater red to green ratio (R/G > 1), which may expand their potential applications in biological imaging and sensing fields.

Enhanced electromagnetic interference shielding performance of geopolymer nanocomposites by incorporating carbon nanotubes with controllable silica shell

The development of construction materials with exceptional electromagnetic interference (EMI) shielding performance is urgently needed to restrict the admittance of electromagnetic (EM) radiation. In this work, silica (SiO2)-coated carbon nanotubes (S-CNT) with different shell thicknesses (∼7, ∼10, and ∼15 nm) were prepared by a sol-gel method. The effect of SiO2 shell thickness on the EMI shielding performance of the resulting geopolymer nanocomposites was studied. The coated SiO2 shell effectively facilitated the dispersion of CNT in the geopolymer matrix due to the chemical reaction between SiO2 and the geopolymer. The dispersability of modified CNT could be further improved by increasing the thickness of the SiO2 shell. However, electron delocalization was hindered by the insulating SiO2 shell. The conductive nature of CNT was restored during geopolymerization when the SiO2 shell was thin. A high EMI shielding effectiveness (SE) of 24.2 dB was achieved for the geopolymer nanocomposite containing 5 vol% S-CNT with a thin SiO2 shell. The value achieved was more competitive than reported composites for construction when the sample thickness and filler content were considered.

Vanadia nanoparticles encapsulated in mesoporous silica as a rattle-like structure for oxidation of dibenzothiophene: A kinetic study

A rattle-like structure of V2O5 encapsulated in mesoporous silica was successfully prepared through a surfactant-supported selective etching strategy. The structural analysis showed that V2O5 nanoparticles in the core of mesoporous hollow silica spheres with void diameter ∼290 nm, V2O5 core diameter ∼93 nm, amorphous SiO2 shell thickness ∼17 nm, surface area of ∼368.19 m2/g and average pore radius of 16 nm. The as-prepared material was employed in catalytic oxidation of dibenzothiophene (DBT) in the presence of H2O2 as an oxidizing agent at different conditions of temperature, contact time and initial concentration using a batch system under either stirring or ultrasonication. The ultrasonication was found to be more effective (∼100%) and faster in oxidation process than the stirring (∼68%, after 5 h). The analysis of the outputs significantly indicated the adsorption of the produced sulfone onto the catalyst surface. The catalytic system exhibited high removal efficiency, qe (∼493 mg/g), as detected experimentally at ambient condition. The thermodynamic analysis confirms the spontaneous physic-sorption nature of the adsorption process with adsorption energy ∼2.155 kJ/mol. The intra-particle diffusion model indicates that the process passes through three stages to attain the equilibrium state.