Ultrasonic-assisted Sol Gel Method Research Articles

Effects of Mo doping on the structure, adsorption performance, and photocatalytic activity of LaFeO3 nanoparticles: Experimental and DFT studies

In this study, a series of Mo-doped LaFeO3 composite photocatalyst nanoparticles (x-LFMO, x = 0.33, 0.5, 0.67) were synthesized by ultrasonic-assisted sol–gel method under controlled Mo doping. X-ray diffraction (XRD) analyses indicate that Mo substitutes one-third of the Fe atoms in the B site of the LaFeO3 to form orthogonal perovskite structures LaFe0.67Mo0.33O3, which is the only pure phase crystal formed at stoichiometric Fe to Mo ratios of 2:1, 1:1, and 1:2, respectively. SEM and N2 adsorption/desorption revealed significantly smaller particle sizes (30–50 nm) and the formation of rich channels after Mo doping, thus enriching the specific surface area and pore size dispersion. DRS confirmed that the Mo-doped LFO composites exhibit significantly enhanced absorption in the visible region. This can be further explained by DFT theoretical calculations of energy band structures and density of states, which demonstrate that the effective mass of the electrons in LaFe0.67Mo0.33O3 is reduced and the off-domain properties of the electrons are enhanced, facilitating the excitation and transport of the photogenerated electrons. Kinetic studies showed that Mo-doped composite nanoparticles exhibit excellent adsorption capacity for quinoline, indole, and pyridine, and the pure phase LaFe0.67Mo0.33O3 and 0.5-LFMO performed well for them with removal efficiencies (>98 %) under visible light irradiation. Based on experimental observations and theoretical insights, it is suggested that the higher quantum yield and photocatalytic reactivity of x-LFMO composites are attributed to the bulk oxygen mobility and surface oxygen reactivity promoted by the octahedral distortion of BO6 in LaFe0.67Mo0.33O3 and the heterogeneous structure formed at the interface of the two phases.

Effect of TiO2/Fe2O3 nanopowder synthesis method on visible light photocatalytic degradation of reactive blue dye

Water pollution and scarcity of clean water are major issues of concern globally. In this study, titanium dioxide (TiO2) photocatalyst doped with ferric oxide (Fe2O3) was used to degrade reactive blue dye (171) using sunlight irradiation. Two approaches were employed to synthesize the photocatalyst: synthesis of ferric oxide and titanium precursor through ultrasonic-assisted sol-gel method and using iron (III) nitrate nonahydrate with commercial titanium dioxide. The photocatalysts were characterized using FTIR Spectroscopy, SEM, XRD analyses, and UVDRS to determine their chemical composition, morphology, crystallinity, and light absorption, respectively. The effect of contaminant concentration (1–3 ppm), solution pH and photocatalyst type on the degradation efficiency was studied. Doping enabled visible light absorption as confirmed by the UVDRS analysis. Solar photocatalytic degradation resulted in complete (100 % removal) of the dye within 2 h under solar irradiation for all concentrations of the dye studied. Furthermore, the photocatalysts exhibited superior performance in both neutral and acidic solutions compared to basic ones. After four cycles, the dye removal efficiency has decreased by less than 15 % for all the photocatalysts confirming the significant activity and high stability of the nanocomposite. The increased dye photodegradation efficacy of Fe2O3 doped TiO2 under sunlight irradiation is attributed to the narrowing of the photocatalyst's bandgap from 3.76 eV (in pure TiO2) to 2.83 eV. This narrowing of the bandgap enhances the absorption of visible light from sunlight, thus making this photocatalyst effective under sunlight and eliminating the use of electricity which is a requirement for ultraviolet photocatalysis.

Preparation of layered double oxides encapsulated in carbon nanotubes to boost selective synthesis of higher alcohols from syngas: Modifying hydrogenation activity and restricting particle sizes by confinement effect

In this work, CuZnAl layered double oxides (LDOs) were encapsulated in carbon nanotubes (CNTs) with different diameters by an ultrasonic-assisted sol-gel method. The CuZnAl LDOs filled in CNTs showed higher catalytic activity and good selectivity for higher alcohols. The catalysts were investigated by varied characterization technologies in order to explore confinement effect of CNTs. It is found that distortion of octahedral unit structure in LDH precursor is enhanced by confinement effect of CNTs. The electron-deficient inner surfaces of CNTs are responsible for the efficient dissociation of CO adsorbed inside CNTs. In addition, hydrogenation ability of the LDOs filled in CNTs is improved due to an obvious decrease in reduction temperature and auto-reduction effect of CNTs, and the restriction effect of CNTs on growth of LDO nanoparticles lead to a rise in their specific surface area. As mentioned above, the changes in structure and properties of LDOs loaded inside CNTs facilitate conversion of syngas into higher alcohols. Moreover, CNTs with small inner size show stronger confinement effect.

Ultrasound-assisted sol-gel synthesis, characterization, and photocatalytic application of ZnO nanoparticles

In this study we synthesized nano-sized ZnO particles by ultrasonic-assisted sol-gel method. The materials were, then, sintered at different temperatures of 400 o C, 500 o C, 600 o C, and 700 o C. The structural, morphological, and optical properties of the obtained ZnO nanoparticles were characterized by XRD, UV VIS, FE-SEM, and TEM. The results showed that ZnO nanoparticles have a hexagonal wurtzite crystalline structure, spherical and hexagonal shapes, and an average size of 22-30 nm. ZnO nanoparticles were used as photocatalysts to decompose methylene blue under ultraviolet light. The results showed that the materials are able to decompose methylene blue under ultra-violet lights. The material sintered 600o C achieved the highest efficiency. From that, it can be concluded that ZnO nanoparticles have potential applications as photocatalysts for organic dyes removal in aqueous solutions.

Catalytic Pyrolysis of the Green Microalgae Botryococcus braunii over Ni/SBA-15 Prepared by the Ultrasonic-Assisted Sol-Gel Method.

The pyrolysis of the green microalgae Botryococcus braunii in the absence and the presence of Ni/SBA-15 prepared by the ultrasonic-assisted sol-gel was investigated using pyrolysis-gas chromatography-mass spectroscopy (Py-GC/MS). Pyrolysis experiments were performed at 350, 450, and 550 °C under helium (He) flow. In the absence of a catalyst, the chemical composition of pyrolysis products at different temperatures, based on the relative peak area, comprised protein/amino acid derivative products of 9-15%, carbohydrate derivative products of 5-10%, lipid derivative products of 13-26%, and chlorophyll derivative products of 24-26%. For catalytic pyrolysis, the chemical composition of pyrolysis products comprised protein/amino acid derivative products of 5-15%, carbohydrate derivative products of 18-19.5%, lipid derivative products of 14-27%, and chlorophyll derivative products of 15-20%. The addition of 10% Ni/SBA-15 enhanced the production of aromatic compounds, such as furans, furfurals, alkyl aromatics, and nitrogen aromatic compounds. These were the thermal degradation products of carbohydrates and proteins. However, the amount of fatty acids and phytol fragments in the pyrolysis of Botryococcus braunii decreased in the presence of catalyst. Thermogravimetric analyses showed that the temperature range for the pyrolysis of Botryococcus braunii was 135-547 °C, while that of the catalyzed pyrolysis was 135-532 °C. There was a decrease in pyrolysis yield after incorporating Ni/SBA-15, which may be due to coke formation.

Activation of bisulfite by LaFeO3 loaded on red mud for degradation of organic dye.

In this study, red mud (RM) was used as a support for LaFeO3 to prepare LaFeO3-RM via the ultrasonic-assisted sol-gel method for the removal of methylene blue (MB) assisted with bisulfite (BS) in the aqueous solution. Characterization by scanning electron microscopy and the Brunauer-Emmett-Teller method indicated that LaFeO3-RM exhibited a large surface area and porous structure with a higher pore volume (i.e. 10 times) compared with the bulk LaFeO3. The XRD, XPS and FTIR results revealed that the support of porous RM not only dispersed LaFeO3 particles but also increased Fe oxidation capability, oxygen-containing functional groups and chemically adsorbed oxygen (from 44.3% to 90.3%) of LaFeO3-RM, which improved the catalytic performance in structure and chemical composition. MB was removed through the synergistic effect of adsorption and catalysis, with MB molecules first absorbed on the surface and then degraded. The removal efficiency was 88.19% in the LaFeO3-RM/BS system under neutral conditions but only 27.09% in the LaFeO3/BS system. The pseudo-first-order kinetic constant of LaFeO3-RM was six times higher than that of LaFeO3. Fe(III) in LaFeO3-RM played a key role in the activation of BS to produce by the redox cycle of Fe(III)/Fe(II). Dissolved oxygen was an essential factor for the generation of . This work provides both a new approach for using porous industrial waste to improve the catalytic performance of LaFeO3 and guidance for resource utilization of RM in wastewater treatment.

On the structural, refractive index and energy bandgap based optical properties of Lithium ferrite nanoparticles dispersed in silica matrix

Lithium ferrite nanoparticles dispersed in silica matrix [Li0.5Fe2.5O4]1–x[SiO2]x (x = 0, 50–90%) have been synthesized using ultrasonic assisted sol–gel method. Agglomeration due to higher surface energy and interparticle interactions is reduced due to dispersion in silica; which modifies the nanoparticle surface and revamp properties of the system. X–ray diffractometer (XRD) measurement reveals simple cubic spinel structure without any impurities. Dynamic magnetic field susceptibility studies show that reversible nature of magnetic domain walls dominates over the irreversible nature. Energy band gap (Eg) determined from UV–Visible (UV–Vis) spectroscopy shows an escalation (1.47 eV to 1.59 eV) for change in silica from 0% to 90%. An empirical formula for refractive index as μ = A(silica content)2+B(silica content)+C has been derived using theoretical fit. With increase in silica content, the refractive index, optical dielectric constant, dielectric susceptibility and oxygen packing density show decrements from 3.82 to 1.77, 8.1204 to 7.6825, 0.6465 to 0.6117 and 70.3157 to 60.974, respectively. The reflectivity, absorption coefficient, molar refractive index, molar electronic polarizability, reflection loss, polaron radius and optical basicity also show reduction. This is attributed to change in density and interparticle interaction due to change in silica content. Dielectric polarizability, transmission coefficient and metallization criterion show increment from 14.85 Å3 to 39.29 Å3, 0.5968 to 0.6086 and 0.2698 to 0.2808; respectively. Observed effects have been ascribed to higher strain, reduction in reflection loss and more non-metallic nature of the samples. Swift changes in parameters indicate their fine tuning through optimum magnitude of silica.

Effect of silica matrix on structural, optical and electrical properties of Li0.5Fe2.5O4 nanoparticles

Lithium ferrite nanoparticles were dispersed in silica matrix to minimize agglomeration. Structural and electrical properties of [Li0.5Fe2.5O4]1–x[SiO2]x (x = 0, 50–90%) nanocomposites synthesized using ultrasonic assisted sol–gel method have been investigated. X–ray diffraction (XRD) measurement confirms phase purity of all the nanocomposites. Crystallite size varies gradually from 29.08 to 17.54 nm with increase in silica content. Higher absorption in dispersed samples compared to pure Lithium ferrite is observed by ultra–violet visible (UV–Vis) measurement. Complex impedance spectroscopy was employed where permittivity and conductivity plots were theoretically fitted using Cole–Cole model and Jonscher's power law, respectively.

Structures and Properties of KxCryNi1-x-yO Dielectric Materials Prepared by an Ultrasonic-Assisted Sol-Gel Method

Abstract KxCryNi1-x-yO (x = 0.05-0.20, y = 0.02) dielectric materials were prepared using a facile simple green ultrasonic-assisted sol-gel method. All samples have a main phase consisting of a cubic NiO structure and with nanoscale crystallite sizes (28.58-37.51 nm). However, secondary phases were also observed for the samples with x values exceeding 0.10. The fractured surface microstructures of the samples with x values less than 0.15 exhibited uniformly distributed spherical grains. Other samples showed irregularly shaped grains. The grain sizes were larger when x was increased to 0.15 and exhibited increased grain growth probably due to substitution of K ions into the NiO lattice. However, a reduction of grain sizes was observed in the sample with x = 0.20, possibly due to inhibition of the grain growth by the secondary phase. At room temperature and a frequency of 1013 Hz, the highest dielectric constant of 2.25 × 104 was obtained for the samples with x = 0.15.

Solvent-dependent structural and optical properties of Cu2MSnS4 synthesized via ultrasonic-assisted sol–gel method

Herein, structural and optical properties of Cu2MSnS4 (M = Co and Fe) nanoparticles synthesized by ultrasonic-assisted sol–gel method using two different solvents are studied. XRD study shows the nanoparticles with tetragonal kesterite structure and crystallite size in the range of 4–7 nm. XPS study reveals the oxidation state of constituent elements. The optical band gap and textural properties like surface area and pore size are estimated through UV–VIS–NIR and nitrogen adsorption–desorption analyses.

Enhanced Photocatalytic Degradation of Caffeine Using Titanium Dioxide Photocatalyst Immobilized on Circular Glass Sheets under Ultraviolet C Irradiation

This work presents the development of titanium dioxide (TiO2) film immobilized on circular glass sheets for photocatalytic degradation of caffeine under ultraviolet C (UVC) irradiation. TiO2 was synthesized through the ultrasonic-assisted sol–gel method and immobilized on circular glass sheets by the doctor blade technique. Polyvinylpyrrolidone (PVP) was used to mix with the TiO2 precursor solution to enhance film adhesion on the glass surface. TiO2 film was mainly composed of anatase phase with a small amount of rutile phase. Caffeine removal was found to increase with increasing irradiation time. Caffeine (20 mg/L) in the synthetic wastewater could not be detected after 3 h of UVC irradiation. The reaction rate of caffeine degradation followed the pseudo-first-order model. The concentrated caffeine solutions required a longer irradiation time for degradation. The used TiO2-coated glass sheets could be easily separated from the treated wastewater and reusable. The caffeine removal efficiency of TiO2-coated glass sheets in each cycle maintained a high level (~100%) during fifteen consecutive cycles.

Construction of CeO2/TiO2 heterojunctions immobilized on activated carbon fiber and its synergetic effect between adsorption and photodegradation for toluene removal

Toluene, as one of the most representative volatile organic compounds (VOCs), poses a serious threat to the atmospheric environment and human health. Herein, cerium dioxide (CeO2)/TiO2 immobilized on activated carbon fiber (ACF) is fabricated by ultrasonic-assisted sol-gel impregnation method for toluene removal. Characterizations of CeO2/TiO2/ACF composites reveal that CeO2 disperses or covers the surface of TiO2/ACF, and Ce4+ does not enter the lattice of TiO2 to replace Ti4+. The TEM and UV-vis analysis indicate the formation of heterojunction between TiO2 and CeO2. The Ce4+/Ce3+ redox centers significantly boost the separation efficiency of electron-hole pairs. The maximum removal efficiency of 1.5% CeO2/TiO2/ACF can reach up to 90%, much higher than 54% over TiO2/ACF. The CeO2/TiO2/ACF composites exhibit high removal efficiency of toluene due to the synergetic effects between adsorption and photodegradation. The gas-phase photodegradations are benzene, benzaldehyde, hexane, phenol, O-xylene, and phenylethyl acetate.

Synthesis of Fe<sub>3</sub>O<sub>4</sub>/TiO<sub>2</sub> Nanocomposite as Photocatalyst in Photoreduction Reaction of CO<sub>2</sub> Conversion to Methanol

TiO2 modified Fe3O4 nanocomposite as photocatalyst in CO2 indirect reduction was synthesized by an ultrasonic-assisted sol-gel method and its photocatalytic activity was studied as well. The modification of the TiO2 composite was attempted to modify titanium dioxide to have better performance as a photocatalyst. Magnetite synthesis was carried out by the sono-coprecipitation method with the addition of the capping agent. The magnetite was coated with TiO2 via the sol-gel method under ultrasonic irradiation. The products were characterized by X-ray diffraction (XRD), Fourier transforms infrared spectrophotometry (FT-IR), transmission electron microscopy (TEM), and turbidimetry. The final product was also analyzed by diffuse reflectance UV-Visible (DR-UV) and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX). The product of indirect reduction was analyzed by gas chromatography-mass spectrometry (GC-MS). Photocatalytic reaction with Fe3O4/TiO2 nanocomposite produced a higher concentration of methanol than using TiO2. Methanol concentration produced from the photocatalytic reaction using TiO2 and Fe3O4/TiO2 was 6.63% and 16.82%.

Controllable synthesis of mesoporous alumina as support for palladium catalysts and reconstruction of active sites during methane combustion

Uniform mesoporous alumina (MA) nanospheres with excellent thermal stability and controllable pore size distribution were facilely obtained through ultrasonic assisted sol-gel method then taken as carriers for synthesizing a series of supported palladium catalysts. Results evidenced that the pore size distribution of MA significantly affected the catalytic performance of as-prepared catalysts. More importantly, the methane pretreatment tuned valence state of palladium species and distribution of surface oxygen species, along with promoting the adsorption of CH4 on catalysts and the generation of CH3∗ group to form methane-derived adsorbates. Moreover, the synergistic effect of PdO and surface adsorbed oxygen effectively activated CH4 and invoked the oxidation of methane-derived adsorbates, hence boosting the catalytic activity with the 90% CH4 conversion temperature (T90) decreased by 40 °C relative to the unpretreated catalyst. Noticeably, the T90 of Pd/MA(CH4) catalyst could be attained at 380 °C after subsequent long term and cyclic stability test.

Ultrasonic-assisted sol–gel synthesis of TiO2 nanostructures: Influence of synthesis parameters on morphology, crystallinity, and photocatalytic performance

The influence of synthesis parameters using the ultrasonic-assisted sol–gel method on the properties of TiO2 nanostructures was studied. Different synthesis conditions such as long stirring time, type of acid used as the catalyst (weak or strong acid), and calcination temperature were explored and their influences on the morphology, size, crystallinity of nanostructures, and photocatalytic performance were evaluated. TiO2 nanostructures were characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, X-ray diffraction, and ultraviolet–visible diffuse reflectance spectroscopy. Moreover, degradation photocatalytic tests were performed using methylene blue as the polluting model. Changes in the morphologies and sizes of nanostructures were observed by modification of the stirring time using this sonication process. Moreover, the use of a weak acid, such as acetic acid, produced nanostructures with higher anatase proportion, larger crystallite size, and larger nanoparticle size compared with the use of a strong acid such as nitric acid. In addition, changes in crystalline phases were observed with an increase in the calcination temperature. Finally, the photocatalytic performance was influenced mainly by the changes in the crystalline phases, which were dependent on the type of acid catalyst and the calcination temperature.

Effect of titanium dioxide on the structural and electrical conductivity of cadmium oxide

Paint pigments belong in the daily-uses classification which are required to have a certain set of substantial qualities, such as; it is needed to be corrosion proof, rust proof (which further leads to longer life), thermally stable, should not react with the environment etc. Sol-Gel Auto-combustion and Ultrasonic Assisted Sol-Gel method was employed on to obtain CdO and TiO2 nanopowders respectively and their composite mixture was studied to understand the outcomes of incorporating TiO2 in another metal oxide CdO. The structural and morphological studies of the pure and the blended composition were analysed with the help of XRD, FTIR, Raman Spectroscopy and FESEM while the conductive nature was investigated through Maxwell-Wagner model and Koop’s phenomenological theory. The formation of CdO and anatase TiO2 was confirmed through XRD with the emergence of standard peaks for both the mentioned metal oxides. The characteristic FTIR peaks were acquired for CdO (410.05–678.41 cm−1) and TiO2 (845.45–850.87 cm−1 and 1391.45 cm−1) and the standardised Raman peaks were also obtained for both CdO (144.66–954.01 cm−1) and TiO2 (147.49–634.52 cm−1). The FESEM study showed the structural formation for CdO and TiO2 while the EDX analysis showed the emergence of peaks of Cd, O & Ti for the studied sample cases. The Dielectric Analysis revealed the drop in the conductive graph. The fore-mentioned composite sample can have its consideration for the raw materials used in paints.

Study on adsorption coupling photodegradation on hierarchical nanostructured g-C3N4/TiO2/activated carbon fiber composites for toluene removal

The hierarchical nanostructured g-C3N4/TiO2/activated carbon fiber (ACF) composites are fabricated by simple ultrasonic assisted sol–gel method to removal toluene gas. The results show g-C3N4/TiO2 is evenly loaded onto the ACF surface in the form of a smooth film. The g-C3N4/TiO2/ACF possess strong photocatalytic activity, and its removal efficiency is twice as high as that of TiO2. Compared with TiO2, photoluminescence fluorescence (PL) intensity of g-C3N4/TiO2/ACF decreases nearly 10 times. Interestingly, the significantly enhanced removal efficiency is due to the synergetic effects of adsorption coupling photodegradation and the formation of Ti–O–C bonds between g-C3N4/TiO2 and ACF. The chemical bonding interaction accelerates the separation efficiency of photogenerated charge carriers. The removal efficiency and adsorption amount can be up to 94% and 140.55 mg/g for toluene concentration of 400 mg/m3 and space velocity of 1000 h−1 with 6% g-C3N4/TiO2/ACF. The space-time-yield of g-C3N4/TiO2/ACF reaches 141.06 g h−1 L−1 much higher than that of ACF (73.29 g h−1 L−1) and g-C3N4/TiO2 (64 g h−1 L−1). The possible photodegradation pathway and mechanisms are proposed. Therefore, the g-C3N4/TiO2/ACFs porous composites possess excellent application potential for elimination volatile organic compounds from atmospheric environment.

Biodiesel production using prepared novel surface functionalised TiO2 nano-catalyst in hydrodynamic cavitation reactor

In this present research work, a way to prepare TiO2-Cu2O nanoparticles composites and its the catalytic activity for the preparation of biodiesel from thumba oil under hydrodynamic cavitation method is reported. Firstly, TiO2 nanoparticles were prepared by ultrasonic-assisted sol-gel method using titanium tetra-isopropoxide (TTIP) as a precursor. TiO2-Cu2O nanoparticles composites were prepared by an electrochemical method and the properties were determined by X-ray diffraction (XRD) and Scanning electron microscopy (SEM). Prepared TiO2-Cu2O nanoparticles were effectively used as a catalyst in the synthesis of Thumba ethyl ester (Biodiesel) by a transesterification reaction between thumba oil and ethanol in hydrodynamic cavitation reactor. The effect of system geometry and inlet pressure on the conversion of triglycerides has been reported. The effect of parameter showed that more than 60% conversion of TG can be obtained with orifice plate of 2 mm hole diameter and 20 no of holes at optimum values of 80 °C in 1 h with 1:6 oil to methanol molar ratio and catalyst concentration of 1.6% in the oil. The prepared TiO2-Cu2O nanoparticles were useful for the biodiesel production up to 60% conversion of triglycerides from thumba oil in hydrodynamic cavitation reactor.

Response Surface Methodology Optimization of Mono-dispersed MgO Nanoparticles Fabricated by Ultrasonic-Assisted Sol–Gel Method for Outstanding Antimicrobial and Antibiofilm Activities

Magnesium oxide (MgO) nanoparticles are one of the highly significant compounds in construction. The novelty concentrated on using sol–gel technique coupled with ultrasonication for synthesis of MgO nanoparticles to prevent the agglomeration and its effect on the size was investigated. The synthesized samples were characterized by TGA, DSC, XRD, FTIR, SEM, EDX mapping, DLS, and HRTEM. Antimicrobial and antibiofilm activities of MgO nanoparticles were investigated against multidrug-resistant microbes causing-urinary tract infection (UTI). TGA, XRD, and FTIR characterization were used to identify the calcination temperature, characterization peaks, and functional groups of MgO nanoparticles, respectively. DLS technique confirmed the particle size distribution which found to be 21.04 nm. HRTEM and SEM/EDX mapping showed that MgO nanoparticles are pure, spherical and the average particle size is 19.2 nm. MgO nanoparticles showed a promising antimicrobial effect against all UTI-causing pathogens. It showed a prominent antimicrobial capability against Staphylococcus aureus, Escherichia coli and Candida albicans by 19.3 mm, 16.1 mm and 15.2 mm ZOI, respectively. Additionally, they showed improved biofilm inhibition as 95.65%, 84.23%, and 76.85% against C. albicans, E. coli and S. aureus, respectively. Therefore, due to these outstanding properties, this study could give insights for solving serious industrial, pharmaceutical and medical challenges throughout the utilization of new nanoparticle-based approach.

Ultrasonic-Assisted Sol–Gel Synthesis of Core–Shell Silica Particles for High-Performance Liquid Chromatography

Core–shell particles (CSPs), also known as superficially porous particles or fused-core particles, consisting of a solid core and a porous shell, have emerged as an advanced technology in high-performance liquid chromatography (HPLC). We report here an ultrasonic-assisted sol–gel method for the fabrication of CSPs with uniform mesoporous silica shell using tetraethoxysilane as the silica source and dodecylamine as a catalyst, template and porogen agent in a methanol–water solution. Instead of stirring, sonication was adopted to guarantee the particles monodispersity and uniformity. The shell thickness between 300 and 700 nm could be obtained by adjusting the sonication time and the volume ratio of methanol–water. Pore sizes from 3.4 to 8.5 nm were tuned by hydrothermal treatment. The C18-bonded 2.7 μm CSPs with a shell thickness of ~ 500 nm showed some advantages over a commercial 1.7 μm BEH column, and successfully applied for the analyses of a Chinese medicine and peptides. The CSPs could be a promising candidate as HPLC packing materials.