Precipitation Method Research Articles

Coral-like Co-doped ZnO nanostructures for enhanced triethylamine detection

In this work, coral-like Co-doped ZnO nanostructures were obtained using simple precipitation and hydrothermal methods. Co-doping reduced the composite particle size to 20 nm, and the controlled growth direction formed a larger adsorption area. The gas sensor results suggest that the maximum response to triethylamine at 200 °C was achieved at 5 mol% doping content. The sensor also performed well for the 30-day stability test, displaying excellent selectivity and repeatability. Besides, 5CZO showed a response-recovery time of 52/70 s and a good response to different gas concentrations. The doping mechanism for the improved gas sensing performance with triethylamine was thoroughly investigated.

Study on Preparation and Properties of Pickering Emulsions Prepared by Carboxymethyl Starch‐Xanthan Gum Nanoparticles

AbstractIn this work, carboxymethyl starch‐xanthan gum nanoparticles (CXN) with different ratios are prepared by ethanol precipitation method. The effects of different ratios, NaCl content, and pH on the particle size and zeta potential of the nanoparticles are investigated, as well as the rheological properties and stability of the CXN emulsions. The results show that with the increase of xanthan gum (XG), the particle size, and zeta potential of the nanoparticles decrease and the prepared emulsions have higher shear stress and viscosity, as well as greater thermal and storage stability. Changes in pH and NaCl concentration significantly affect the particle size and zeta potential values of the nanoparticles. Excess acids or bases increase the viscosity of the emulsions. At low salt concentrations (0.05 M), the emulsion viscosity increases significantly, after which the emulsion viscosity decreases with increasing salt concentration. Neutral pH conditions at room temperature are not conducive to the stability of the emulsions. At high temperatures (100 °C), high salt concentrations, excessive acids or bases can destabilize emulsions. This study provides a new way to reduce the particle size of nanoparticles and a feasible strategy for developing long‐term stable Pickering emulsion.

Synergetic effect of Fe decorated MnO2 nanocatalyst application in propane and benzyl alcohol oxidation

In heterogeneous catalysis, one of the key challenges is to develop inexpensive and abundant materials. Herein, spherically shaped α–Fe2O3 nanoparticles decorated over MnO2 nanorods surface (Fe/MnO2NRs) was synthesized via hydrothermal followed by co–precipitation methods. Experimental results indicated that the inclusion of Fe in MnO2NRs promotes a strong interaction that increases the reducibility of Mn4+ to Mn3+ and surface adsorbed oxygen (Oads.), which in turn increases the activation of surface oxygen on MnO2NRs. The 10 wt% Fe–loaded catalyst (10Fe/MnO2NRs) exhibited the highest catalytic activity. It was observed that oxidizing 10 % (T10), 50 % (T50), and 90 % (T90) of propane required temperatures of 140 °C, 180 °C, and 220 °C, respectively. This catalyst showed stability in H2O atmospheres and apparent activation energy as low as 52.54 kJ mol−1. In addition, the vapour phase oxidation of benzyl alcohol (BnOH) over different Fe–loaded MnO2NRs catalysts is investigated. The rate of BnOH oxidation over 10Fe/MnO2NRs catalyst is 1.71 times greater than bare MnO2NRs at 240 °C. The increased oxygen vacancies can improve the oxidation activity of propane and BnOH by facilitating the adsorption and activation of O2 to produce reactive oxygen species. This work offers a novel approach to increase manganese oxides surface oxygen activity, which can be used to create efficient catalysts for the low–temperature decomposition of volatile organic compounds (VOCs) and other organic functional group transformations via oxidation reaction.

Improving yield, functional properties, and aroma profile of rice bran protein through innovative extraction and precipitation methods

Rice bran is a milling byproduct and rice bran protein (RBP) is a promising source of plant-based protein. This study investigated the impact of alkaline and acid extractions followed by isoelectric point (IEP) and heat coagulation precipitations on the quality and functionalities of RBP. Alkaline extraction, followed by IEP and heat coagulation, showed the highest protein recovery of 48.77%, which is double that of conventional alkaline extraction and IEP. The FTIR data showed that β-sheet and α-helix content reduced; however, random coil and β-turn increased by acid and heat addition. Addition of heat coagulation to IEP after alkaline extraction increased solubility from 62.94% to 94.74%. However, the emulsification and surface hydrophobicity were decreased during heat and acid-assisted extraction. The in-vitro digestibility was the highest at 83.57% in alkaline-acid extraction, followed by heat and IEP. The aroma profile of RBP shows a complex mixture of ethanol-2-butoxy, 2-methyl-4-vinyl-phenol, 2,4—heptagonal, (E,E)-, Undecane, and 5-methyl to form a typical flavor with waxy and rancid undernotes. The total amount of volatile compounds in conventional extraction was 1.97 μg/g, while alkaline-acid extraction with IEP had only 0.87 μg/g. The RBP from alkaline-acid extraction with IEP showed the least volatile compounds and most neutral proteins.

Influence of morphology, crystal structures on the enhanced photoluminescence dynamics, zeta potential, and AC resistance of disc shaped cesium oxidex@cobalt oxide nanostructures

In the present study, cesium oxidex@cobalt oxide (Cs2Ox@Co3O4) (x = 5, 10 and 12 wt%) nanostructures (NS) were successfully synthesized by chemical precipitation method and characterized by XRD (X-ray diffraction), SEM (scanning electron microscope), EDX (energy dispersive X-ray), XPS (X-ray photoelectron spectroscopy), BET (Brunauer-Emmett-Teller), Raman, and UV–visible analytical techniques. XRD studies revealed the formation of the mixed phase of orthorhombic/monoclinic crystal structure. Disc shaped morphology of the cesium oxidex@cobalt oxide NS was noticed from SEM images. Redshift in optical absorbance and decrease in optical band gap (Eg) resulted in increase in Cs1+ concentration. Room temperature photoluminescence (RTPL) studies of cesium oxidex@cobalt oxide NS at various excitation wavelengths showed sharp and broad emission peaks located at 668.2 nm (red), 675.1 nm (red), 561.8 nm (yellow-green), 834.5 nm (near infrared region), 594 nm (yellow). Steady state photoluminescence (SSPL) studies revealed a sharp emission peak at ∼ 428.0 nm (violet) with large stoke’s shift (21.1 to 590.0 eV). The zeta potential studies showed a decrease in conductance from 62 to 57 μs with an increase in mobility of the charge carriers (0.4 to 1.08 μ/s V/cm) and an increase in zeta potential (31.90 to 82.92 mV). AC resistance studies at various temperatures showed inducting coupling phenomenon in cesium oxidex@cobalt oxide NS with DC resistance of cesium oxide5 wt.%@cobalt oxide was found to be 8.2 × 10–4 Sm–1. The relaxation frequency of cesium oxide12 wt.%@cobalt oxide NS was found be 1.2 × 105 Hz. The synthesized NS is a promising candidate for optoelectronics and photonic applications.

P-functionalization of Ni Fe − Electrocatalysts from Prussian blue analogue for enhanced anode in anion exchange membrane water electrolysers

Efficient hydrogen generation from water-splitting is widely acknowledged as a priority route to promote the hydrogen economy. Anion exchange membrane water electrolyzers (AEMWE) offer multiple advantages in improving performance and minimizing the cost limitations of current electrolysis technologies. However, the persistence of issues related to the limited electrocatalytic activity of such materials and their poor stability under operating conditions makes developing highly active, stable, platinum-group-metal-free electrocatalysts for oxygen evolution reaction (OER) necessary.We report the development of Prussian blue analogues (PBA)-derived NiFe-based electrocatalysts through a mild aqueous phase precipitation method, followed by thermal stabilization and phosphorus doping. The formation of the NiFe-PBA-precursor with a framework nanocubic Ni(II)[Fe(III)(CN)6]2/3 structure was confirmed by X-ray diffraction, scanning electron microscopy, and inductively coupled plasma analysis. The NiFe-PBA-precursor was subjected to thermal stabilization and phosphorus doping to provide the material with enhanced OER catalytic activity and stability. The existence of OER active sites based on NiFe and NiFeP has been revealed by transmission electron microscopy, X-ray photoelectron spectroscopy, and electrochemical characterization in a three-electrode cell configuration in a 1 M KOH electrolyte. NiFe-PBA and NiFeP-PBA were assembled at the anode side of an AEMWE, resulting in an excellent electrochemical performance both in terms of current density at 2.0 V using 1 M KOH (1.21 A cm−2) and durability, outperforming the benchmark catalyst.

“Synthesis and characterization of TiO2 nanoparticles as brake fluid additives: Viscosity modulation and impact on rheological properties”

TiO2 nanoparticles were synthesized using the reduction precipitation method, verified by powder x-ray diffraction (PXRD) with an average crystallite size of 62 nm and an average particle size of 135 nm from SEM images. Rheological studies of brake fluid with nanoparticle additives revealed that while the fluid generally maintains consistent behavior, a 2 wt.% concentration showed non-Newtonian behavior at 120 °C. Viscosity increased slightly with nanoparticle addition and decreased with rising temperature, with the 0.5 wt.% sample demonstrating the most notable increase of 18.18% at 120 °C. At 30 °C, the 1 wt.% sample exhibited a 4.06% increase. The observed viscosity changes are attributed to higher internal shear stress and the need to manage dispersion solid elements. The Herschel-Bulkley model was effective in predicting sample behavior, and all samples conformed to Reynolds’ equation μ 0 = b e − aT . This research indicates that TiO2 nanoparticles can be effectively used as brake fluid additives, offering potential benefits for high-temperature applications in vehicles. Further optimization using mathematical models such as response surface methodology (RSM) is suggested for improved performance.

Synthesis of a novel flower-like Bi4Ti3O12/AgI Z-type heterojunction for efficient photocatalytic removal of tetracycline antibiotic and RhB

Novel Flowerlike Bi4Ti3O12/AgI (BTO/AgI) Z-type heterojunctions were fabricated via a straightforward in-situ precipitation method. Notably, BTO/AgI exhibited significantly improved photodegradation efficiency for tetracycline (TC) and Rhodamine B (RhB). The rate constants for RhB and TC photodegradation were approximately 20.8 and 2.9 times higher than those of BTO alone, respectively. Furthermore, the photocatalytic efficiency of the BTO/AgI heterojunction is 1.4 times higher than that of the mixture of the two individual photocatalysts, indicating a robust interaction between BTO and AgI. This enhancement in photocatalytic performance was mainly attributed to the effective separation of photogenerated carriers facilitated by the Z-scheme heterojunction, which can be demonstrated by the highest photocurrent density (∼0.307 μA·cm−2) of BTO/AgI, surpassing BTO (∼0.073 μA·cm−2) and AgI (∼0.161 μA·cm−2) by approximately 4.12 and 1.91 times, respectively. Furthermore, three plausible photodegradation pathways of tetracycline were proposed. This study introduces a novel approach for designing and synthesizing high-efficiency Z-scheme photocatalysts for the degradation of TC and RhB in wastewater.

Preparation of structural colors from lignin: Improving the homogeneity between different raw materials by solvent precipitation fractionation

Structural color materials prepared by lignin colloidal spheres (LCSs) have attracted great interest due to their biocompatibility, biodegradability, multifunctionality, and ability to weaken incoherent scattering. However, the lignin raw materials originating from different biomass resources have distinct heterogeneity leading to a big difference in the size of resultant LCSs via self-assembly, which is a major challenge for the preparation of stable structural colors. In this work, we employ the solvent precipitation method to fractionate the crude lignin samples obtained from corncob, softwood, hardwood, and bamboo, respectively. After solvent precipitation fractionation, the self-assembly behaviors of different lignin samples become similar. The LCSs prepared by fractionated lignin samples show quite similar sizes (212, 202, 215, and 210 nm) compared with the LCSs prepared by crude lignin samples (341, 83, 128, and 253 nm). The quantitative atomic force microscope force spectroscopy demonstrates the improved homogeneity of LCSs prepared by fractionated lignin samples is attributed to similar long-ranged intermolecular forces in self-assembly. By employing LCSs as building blocks, the lignin-based pigments with stable structural colors are successfully prepared. The presented colors are independent of the biomass resource types, which benefits the product stability and large-scale production of lignin-based structural color materials.

Plant Protein Resources, Novel Extraction and Precipitation Methods: A Review

ABSTRACTThis comprehensive review explores the diverse landscape of plant protein resources, focusing on novel extraction and precipitation methods that contribute to the advancement of sustainable and efficient protein production. The increasing global demand for plant‐based proteins as a key component of balanced diets has spurred research into optimizing extraction processes from various plant sources. The review encompasses a wide range of plant protein resources, including legumes, cereals, oilseeds, and other plant‐based alternatives. Special emphasis is given to innovative techniques in protein extraction, such as enzyme‐assisted extraction, aqueous extraction, and emerging technologies like ultrasound and microwave‐assisted methods. Additionally, the review investigates novel precipitation methods employed to isolate and purify plant proteins, shedding light on techniques like isoelectric precipitation, salting‐out, and membrane filtration. The integration of sustainable practices in protein extraction, coupled with a focus on minimizing environmental impact, is a central theme throughout the review. By synthesizing current research findings, this review aims to provide a comprehensive overview of the state‐of‐the‐art in plant protein extraction and precipitation methods, offering valuable insights for researchers, industry professionals, and policymakers involved in the rapidly evolving field of plant‐based protein production.

Tuning Electrochemical Performance of Polymer Electrolyte Films through Metal Oxide Incorporation

AbstractWith the escalating global energy demand, the exploration of alternative, easily accessible, and cost‐effective energy sources has become imperative. The diminishing reserves of conventional energy resources underscore the urgency to transition towards renewable energy. Solid polymer electrolytes (SPEs) have gained prominence for energy storage electrochemical devices due to their high flexibility and favorable electrode–electrolyte interactions. This study focuses on synthesizing nano cuprous oxide (CuO) semiconductors via the precipitation method. The prepared CuO nanofiller is homogeneously dispersed into a polymer electrolyte solution. Utilizing the solution cast method, free‐standing polymer electrolyte films are fabricated, exhibiting commendable mechanical stability. Polyvinyl alcohol (PVA) serves as the host material, with potassium iodide (KI) salt, forming the basis for the polymer electrolyte. The resultant electrolyte films underwent comprehensive characterization for their electrical and optical properties. The investigation aims to identify the optimal composition of the electrolyte film with superior conductivity. The selected composition will be employed in the fabrication of various electrochemical devices, demonstrating the potential for enhanced energy storage applications. This work not only contributes to the synthesis of advanced solid polymer electrolyte films but also paves the way for the development of efficient and sustainable energy storage solutions in the realm of renewable energy technologies.

Higher-valent nickel oxides with enhanced two-electron oxygen reduction in advanced electro-Fenton system for organic pollutants degradation

A higher-valent NiO catalyst, enriched with trivalent Ni (Ni3+) and exposed {111} crystal facets, was developed to enhance selective two-electron oxygen reduction (2e– ORR) for electrochemical hydrogen peroxide (H2O2) production, leading to highly efficient organic pollutant removal. The catalyst was synthesized via a precipitation method, incorporating crystal facet and cation vacancy engineering to expose active sites. It demonstrated 96 % selectivity and 59 A g−1 mass activity, attributed to weakened *OOH binding, as shown by density functional theory. Integrated into an advanced electro-Fenton (EF) flow cell, the system achieved 100 % removal of 200 mL of 50 ppm bisphenol A (BPA) in 4 minutes, with 93 % total organic carbon removal within 2 hours. This study provides a scalable and efficient solution for decentralized environmental remediation and wastewater treatment.

Cr-MIL-101 derived nano Cr2O3 for highly efficient dehydrogenation of n-hexane

Nano Cr2O3 (n-Cr2O3) was prepared by the thermolysis of the mesoporous Cr-MIL-101, and its catalytic performance for n-hexane dehydrogenation was investigated and compared with Cr2O3 obtained by traditional method. It is found that dehydrogenation of n-hexane on n-Cr2O3 catalyst can produce n-hexenes and benzene efficiently, and the catalytic performance is related to the calcination temperature. The optimal n-hexane conversion can be obtained on n-Cr2O3 calcinated under 600 °C, is 40.6%, and the selectivities to n-hexenes and benzene are 20.1% and 69.3%, respectively. The conversion of n-hexane for n-Cr2O3 catalyst is decreased with calcination temperature increase, while the catalyst stability in dehydrogenation reaction is enhanced. n-Hexane conversion of p-Cr2O3-1 (obtained by precipitation method) and p-Cr2O3-2 (calcinating Cr(NO3)·9H2O directly) catalysts are very low (<7.5%), and their specific activity for n-hexane dehydrogenation are 1.5 and 1.7 g/(m2·h) respectively, lower than that of n-Cr2O3-600 (2.0 g/(m2·h)). The results of BET, XRD, TEM and FT-IR reveal that n-Cr2O3 is the nanoparticles with large specific surface area that more dehydrogenation active sites are exposed, while p-Cr2O3 is the large particles with extremely low surface area that few dehydrogenation active sites are presented. By contrast, industrial Cr2O3/Al2O3 catalyst possesses the highest specific activity of 2.4 g/(m2·h) due to the dispersion effect of Al2O3. Therefore, highly catalytic activity of n-Cr2O3 for n-hexane dehydrogenation is attributed to the unique properties of small particle, large specific surface area and more exposed active sites. This work not only explains the high dehydrogenation activity of nano-Cr2O3 derived by Cr-MIL-101, but also provides guidance for the precise design and synthesis of high-performance CrOx-based catalyst for the dehydrogenation of alkanes.

Tailoring sub-5 nm Fe-doped CeO2 nanocrystals within confined spaces to boost photocatalytic hydrogen evolution under visible light

This work aimed to study the efficiency of the reverse micelle (RM) preparation route in the syntheses of sub-5 nm Fe-doped CeO2 nanocrystals for boosting the visible-light-driven photocatalytic hydrogen production from methanol aqueous solutions. The effectiveness of confining precipitation reactions within micellar cages was evaluated through extensive physicochemical characterization. In particular, the nominal composition (0–5 mol% Fe) was preserved as ascertained by ICP-MS analysis, and the absence of separate iron-containing crystalline phases was supported by X-ray diffraction. The effective aliovalent doping and modulation of the optical properties were investigated using UV-Vis, Raman, and photoluminescence spectroscopies. 2.5 mol% iron was found to be an optimal content to achieve a significant decrease in the band gap, enhance the concentration of oxygen vacancy defects, and increase the charge carrier lifetime. The photocatalytic activity of Fe-doped CeO2 prepared at different Fe contents with RM preparation was studied and compared with undoped CeO2. The optimal iron load was identified to be 2.5 mol%, achieving the highest hydrogen production (7566 μmol L−1 after 240 min under visible light). Moreover, for comparison, the conventional precipitation (P) method was adopted to prepare iron containing CeO2 at the optimal content (2.5 mol% Fe). The Fe-doped CeO2 catalyst prepared by RM showed a significantly higher hydrogen production than that obtained with the sample prepared by the P method. The optimal Fe-doped CeO2, prepared by the RM method, was stable for six reuse cycles. Moreover, the role of water in the mechanism of photocatalytic hydrogen evolution under visible light was studied through the test in the presence of D2O. The obtained results evidenced that hydrogen was produced from the reduction of H+ by the electrons promoted in the conduction band, while methanol was preferentially oxidized by the photogenerated positive holes.

Enhancing clay soil reinforcement using the MICP-BIN method with biochar-induced nucleation

The microbially induced carbonate precipitation (MICP) method has gained extensive use in the realm of soil stabilization. The combination of MICP with biochar offers potential benefits in terms of simultaneous strength enhancement and vegetation cover enhancement. This study presents a novel microbial solidification technique known as the biochar-induced nucleation (MICP-BIN) method for reinforcing clay soil. Corn stover biochar was employed as an auxiliary material, mixed with dry clay powder, and subsequently reinforced using the MICP technique. Direct shear tests (DSTs), drying experiments, X-ray diffraction (XRD), and scanning electron microscopy (SEM) were also conducted to investigate the efficacy of the MICP-BIN method. Compared with that of the remolded soil, the shear strength of the treated soil exhibited a substantial increase of 22.4%, the CaCO3 content increased by 30%, and the shear strength improved by 389.5%. Similarly, the internal friction angle exhibited increases of 22.7% and 405.2%, while the cohesion showed improvements of 9.4% and 344.3%, respectively. The MICP-BIN method is found to increase suction for a given water content. Further, biochar amended soil possesses highest water retention ability (especially at lower suction magnitude) followed by MICP amended soil, MICP-BIN amended soil and untreated soil. The difference in water retention abilities among various soils is negligible at higher suction magnitude. Further, there is no significant change in air entry value of MICP-BIN amended soil as compared to the untreated soil and MICP amended soil. This study demonstrated the promising results achieved by combining biochar and the MICP-BIN technique, providing a novel approach for reinforcing soft ground.

Fabrication and characterization of lysozyme fibrils/Zein complexes for resveratrol encapsulation: Improving stability, antioxidant and antibacterial activities

Resveratrol (Res), a naturally occurring hydrophobic polyphenol, boasts numerous health-promoting bio-functionalities. However, its limited water solubility and stability impede further applications in the food industry. This study aims to address these challenges by fabricating stable Res-loaded lysozyme fibrils/zein (Ly-F/Z) complexes. The complexes were prepared using an antisolvent precipitation method. The interaction mechanism between Ly-F and zein was elucidated through dynamic light scattering, Fourier-transform infrared spectroscopy and dissociative experiments, revealing the involvement of hydrogen bonding, electrostatic forces and hydrophobic interactions in complex formation. The Ly-F/Z complexes were utilized to encapsulate Res, resulting in an encapsulation efficiency of 82.58 %. X-ray diffraction analysis confirmed the successful encapsulation of Res within Ly-F/Z complexes, presenting an amorphous state. The Ly-F/Z-Res complexes exhibited a “fruit tree” morphology with dense fruit, showcasing remarkable stability, antioxidant and antibacterial activities. Consequently, the Ly-F/Z complexes can serve as promising delivery systems for Res in functional foods.

Investigating the efficacy of Palladium Doped Ceria for the Photodegradation of Azo Dyes

Ceria (CeO2) was prepared by microwave assisted precipitation method while sonothermal method was utilized for the synthesis of palladium doped ceria (Pd-CeO2) photocatalyst. HR-TEM analysis confirms the face centered cubic geometry (FCC) of CeO2. The particle size of Pd-CeO2 calculated from HR-TEM analysis (7.6±2.18 nm) is in close relation with XRD (8.25±0.25 nm). The SAED pattern of Pd-CeO2 shows the poly crystallinity where the d-spacing was 0.31 and 0.30 nm which corresponds to CeO2 and Pd crystal facets 111 and 100 respectively. The amount of dopant and existence of Pd, Ce and O was confirmed from EDX spectra and elemental mapping. BET surface area analysis of CeO2 (64.45 m2/g), Pd-CeO2 (60.20 m²/g) revealed that the decrease in the surface area of CeO2 due to Pd loading which is confirmed by pore volume (0.079 cm³/g) for CeO2 and pore volume for Pd-CeO2 (0.073 cm³/g). The photocatalytic activity of Pd-CeO2 was screened against a model azo dye Acid red-4 (AR-4). The fluctuation of the rate of photodegradation (PD) of AR-4 was observed under different reaction conditions. Therefore, the reaction parameters were optimized to achieve best catalytic activity up to PD; 98%. The kinetic study suggests that the PD of AR-4 follows 1st order kinetics with regression coefficient (R2=0.973) and rate constant (k=0.024/min). Recycling study revealed the prolong use of catalyst without significant loss of activity. DFT study and experiments revealed the synergism of Pd on the photo response of CeO2. Perhaps this synergistic effect due to metal support interaction, causes redistribution of charges and Fermi energy levels. The synthesized catalyst showed potential application for the treatment of textile industrial effluents.

Controlled synthesis of CeNbZrO solid solution with high thermal stability and application in catalytic degradation of C6H5CH3 and C6H5Cl

A series of CeNbZrO composite oxides with different (CeNb)/Zr molar ratios were prepared by urea homogeneous precipitation method and systematically characterized. The thermal stability, degradation performance and structure-activity relationship of these catalysts for eliminating C6H5CH3 and C6H5Cl mixed pollutants were evaluated. The results indicated that with the increase of ZrO2 content, the catalytic activity of CeNbxZrO increased first and then decreased. Among them, the CeNb3.3ZrO catalyst (Ce/Nb/Zr=2/1/3.3, molar ratio) exhibited the highest catalytic activity (C6H5CH3: T90%=310oC, C6H5Cl: T90%=344oC) and thermal stability. Compared with the traditional CeO2-MnO2 catalyst, the T90% of the CeNb3.3ZrO catalyst in the degradation of C6H5Cl was reduced by 100oC. CeNb3.3ZrO exhibited high specific surface area and strong oxidation ability, which enhanced the redox cycles and promoted the interactions between metal ions. In addition, the formation of Ce2Zr3O10 solid solution made its structure stable even at high temperature. Overall, the optimized CeNb3.3ZrO has broad prospects in the catalytic treatment of volatile organic compounds and some other related fields in thermal catalysis. Environmental implicationC6H5CH3 and C6H5Cl are typical VOCs with certain toxicity, which pollute air environment and cause harm to human health. In this paper, CeNbZrO composite oxides with different (CeNb)/Zr molar ratios were prepared by urea homogeneous precipitation method. It was found that the CeNb3.3ZrO catalyst had higher specific surface area and stronger oxidation ability, and promoted the complete degradation of C6H5CH3 and C6H5Cl at lower temperatures by destroying the C-C, C-H and C-Cl bonds of the reactants.

Sm-MOF decorated cotton for efficient on-demand oil-water separation and organic pollutants removal

Complex wastewater containing oil–water and contaminant mixtures is a constant threat to ecosystems and public health. However, efficient water–oil separation and water treatment are required, with a preference for simple but universal matrices for possible large-scale applications. Herein, effective oil–water separation and organic pollutant removal are simultaneously realized on cotton balls decorated with polydimethylsiloxane combined with a samarium metal–organic framework. Cotton balls containing polydimethylsiloxane (10 %) and Sm-MOF (Synthesis temperature was 110 ℃, 15 mg/L) were successfully prepared by a simple precipitation method, with a high water contact angle of 150.75 ± 1.1°. After pre-wetting with a low surface energy solution, the modified cotton was endowed with repeatable super-wetting transitions between superhydrophobic/superoleophilic and superhydrophilic/underwater superoleophobic properties. In addition to on-demand separations of immiscible oil–water mixtures at a rate of 95 %, water-in-oil emulsions could be separated by the addition of different surfactants. The mechanism of demulsification of the treated cotton ball was studied based on the type of emulsifier and the results of emulsified oil separation. Cotton balls modified with 10 % PDMS and Sm-MOF (Synthesis temperature was 140 °C; 15 mg/L) showed higher adsorption capacity compared to pure cotton balls, adsorbing about 98.7 % of Eriochrome Black T within 2 h. Cotton balls modified by PDMS and Sm-MOF are an effective, safe and green material with promising applications in the simultaneous separation of oil–water mixtures and removal of organic pollutants from water systems.

Titanyl sulfate-based TiO2-paraffin phase change microcapsules: Evaluation of alkyltriethoxysilane modification and thermoregulation applications

Titanium dioxide (TiO2) phase change microcapsules show promising applications in building temperature regulation and heat transfer due to their high thermal reflectivity and high thermal conductivity. Currently, the preparation of TiO2 microcapsules predominantly relies on expensive and highly toxic titanate as a raw material. In this study, a new type of TiO2-paraffin phase change microcapsules was prepared by chemical precipitation method using cheap and low toxic titanium sulfate dihydrate (TSD) as titanium source and alkyltriethoxysilane as modifier. The results showed that when methyltriethoxysilane was used as a modifier and the dosage was 1/3 of TSD, the core-wall ratio was 1:1, and the reaction temperature was 65 °C, the performance of the modified TiO2 phase change microcapsules was the best. The melting enthalpy was 112.8 J/g, the core material content reached 83.70 %, which was 48.06 % higher than that of the unmodified microcapsules, and the melting permeability ratio was 12.88 %. The test chamber containing the sample TiO2 phase change microcapsules underwent a temperature rise-cooling test, transitioning from 25 ℃ to 65 ℃ under simulated solar light conditions. The heating time for the phase change microcapsules with modified TiO2 was 28 % faster compared to those containing unmodified TiO2, while the cooling time was 13.00 % slower. It is shown that the light conversion, as well as the thermal storage capacity of TiO2 phase change microcapsules, are significantly improved after organosilicon modification.