Browse
Submit Data
Databases
API
Help

Dataset Information

23 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Highly Efficient Mesoporous Carbonaceous CeO₂ Catalyst for Dephosphorylation.

ABSTRACT: Phosphorus is fast becoming a critical element, as the global supply and demand are reaching unsustainable levels. Herein, the synthesis, characterization, and applicability of a novel biomass-derived mesoporous carbonaceous material decorated with CeO₂ (CeO₂-S400) as an efficient catalyst for the dephosphorylation of 4-nitrophenyl phosphate disodium salt hexahydrate are reported. The presence and distribution of CeO₂ are evidenced by inductively coupled plasma mass spectrometry (ICP-MS) (118.7 mg/g), high-resolution transmission electron microscopy (HRTEM), and energy dispersive X-ray (EDX) mapping. The apparent rate constant for the efficient catalysis of 4-nitrophenyl phosphate disodium salt hexahydrate was 0.097 ± 0.01 for CeO₂-ES and 0.15 ± 0.03 min^-1 for CeO₂-S400, which followed first-order kinetics. Rate constants normalized by the catalytic loading (k _m) were 80.84 and 15.00 g^-1 min^-1 for CeO₂-ES and CeO₂-S400, respectively, and the normalized rate constants with respect to surface area were 3.38 and 0.04 m^-2 min^-1 for CeO₂-ES and CeO₂-S400, respectively. This indicates that the presence of CeO₂ nanoparticles has a catalytic effect on the dephosphorylation reaction.

SUBMITTER: Sharma A

PROVIDER: S-EPMC9260935 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Highly Efficient Photoelectrocatalytic Reduction of CO2 to Methanol by a p-n Heterojunction CeO2/CuO/Cu Catalyst.

Project description:Photoelectrocatalytic reduction of CO2 to fuels has great potential for reducing anthropogenic CO2 emissions and also lessening our dependence on fossil fuel energy. Herein, we report the successful development of a novel photoelectrocatalytic catalyst for the selective reduction of CO2 to methanol, comprising a copper catalyst modified with flower-like cerium oxide nanoparticles (CeO2 NPs) (a n-type semiconductor) and copper oxide nanoparticles (CuO NPs) (a p-type semiconductor). At an applied potential of - 1.0 V (vs SCE) under visible light irradiation, the CeO2 NPs/CuO NPs/Cu catalyst yielded methanol at a rate of 3.44 μmol cm-2 h-1, which was approximately five times higher than that of a CuO NPs/Cu catalyst (0.67 μmol cm-2 h-1). The carrier concentration increased by ~ 108 times when the flower-like CeO2 NPs were deposited on the CuO NPs/Cu catalyst, due to synergistic transfer of photoexcited electrons from the conduction band of CuO to that of CeO2, which enhanced both photocatalytic and photoelectrocatalytic CO2 reduction on the CeO2 NPs. The facile migration of photoexcited electrons and holes across the p-n heterojunction that formed between the CeO2 and CuO components was thus critical to excellent light-induced CO2 reduction properties of the CeO2 NPs/CuO NPs/Cu catalyst. Results encourage the wider application of composite semiconductor electrodes in carbon dioxide reduction.

| S-EPMC7770658 | biostudies-literature

Efficient NH3-SCR removal of NOx with highly ordered mesoporous WO3(χ)-CeO2 at low temperatures.

Project description:To eliminate nitrogen oxides (NOx), a series of highly ordered mesoporous WO3(χ)-CeO2 nanomaterials (χ represents the mole ratio of W/Ce) were synthesized by using KIT-6 as a hard template, which was used for selective catalytic reduction (SCR) to remove NOx with NH3 at low temperatures. Moreover, the nanomaterials were characterized by TEM, XRD, Raman, XPS, BET, H2-TPR, NH3-TPD and in situ DRIFTS. It can be found that all of the prepared mesoporous WO3(χ)-CeO2 (χ = 0, 0.5, 0.75, 1 and 1.25) showed highly ordered mesoporous channels. Furthermore, mesoporous WO3(1)-CeO2 exhibited the best removal efficiency of NOx, and its NOx conversion ratio could reach 100% from 225 ° C to 350 ° C with a gas hourly space velocity of 30 000 h-1, which was due to higher Ce3+ concentrations, abundant active surface oxygen species and Lewis acid sites based on XPS, H2-TPR, NH3-TPD and in situ DRIFTS. In addition, several key performance parameters of mesoporous WO3(1)-CeO2, such as superior water resistance, better alkali metal resistance, higher thermal stability and N2 selectivity, were systematically studied, indicating that the synthesized mesoporous WO3(1)-CeO2 has great potential for industrial applications.

| S-EPMC5505671 | biostudies-literature

Construction of stabilized bulk-nano interfaces for highly promoted inverse CeO2/Cu catalyst.

Project description:As the water-gas shift (WGS) reaction serves as a crucial industrial process, strategies for developing robust WGS catalysts are highly desiderated. Here we report the construction of stabilized bulk-nano interfaces to fabricate highly efficient copper-ceria catalyst for the WGS reaction. With an in-situ structural transformation, small CeO2 nanoparticles (2-3 nm) are stabilized on bulk Cu to form abundant CeO2-Cu interfaces, which maintain well-dispersed under reaction conditions. This inverse CeO2/Cu catalyst shows excellent WGS performances, of which the activity is 5 times higher than other reported Cu catalysts. Long-term stability is also very solid under harsh conditions. Mechanistic study illustrates that for the inverse CeO2/Cu catalyst, superb capability of H2O dissociation and CO oxidation facilitates WGS process via the combination of associative and redox mechanisms. This work paves a way to fabricate robust catalysts by combining the advantages of bulk and nano-sized catalysts. Catalysts with such inverse configurations show great potential in practical WGS applications.

| S-EPMC6677889 | biostudies-literature

Synthesis and catalytic evaluation of PVP-CeO2/rGO as a highly efficient and recyclable heterogeneous catalyst for multicomponent reactions in water.

Project description:A highly efficient and eco-friendly route for the reduction of graphene oxide (GO) to reduced graphene oxide (rGO) was developed by using polyvinylpyrrolidone coated CeO2 NPs (PVP-CeO2) as a reducing and stabilizing agent. The resulting carbonaceous material, PVP-CeO2/rGO, was well characterized with different spectroscopic techniques such as Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), elemental mapping, Transmission Electron Microscopy (TEM), Raman spectroscopy, powder X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), X-ray Photoelectron Spectroscopy (XPS), and Thermal Gravimetric (TG) analyses. The material exhibited high catalytic potential towards multicomponent reactions for the synthesis of biologically relevant benzodiazepine derivatives in aqueous media. The efficiency of the material for the desired reaction was shown in the form of an excellent product yield (96-98%) and a very short reaction time period (7-10 min). The use of water as solvent and recyclability of the catalyst made the present protocol acceptable from a green perspective.

| S-EPMC9419207 | biostudies-literature

The highly efficient removal of HCN over Cu8Mn2/CeO2 catalytic material.

Project description:In this work, porous CeO2 flower-like spheres loaded with bimetal oxides were prepared to achieve effective removal of HCN in the lower temperature region of 30-150 °C. Among all samples, the CeO2 loaded with copper and manganese oxides at the mass ratio of 8/2 (Cu8Mn2/CeO2) exhibited the highest catalytic activity: the HCN removal rate was nearly 100% at 90 °C at the conditions of 120 000 h-1 and 5 vol% H2O, the catalytic activity of which was higher than for other reported catalysts. The introduction of MnO x could improve the dispersion of CuO particles and increase the total acid sites of the prepared samples. It was proved that the synergy between CuO and MnO x , the chemisorption oxygen, the oxygen vacancies, the Cu2+ and Mn4+ all played an important role in determining the good catalytic activity of the prepared samples. NH3-TPD analysis indicated the introduction of MnO x promoted the conversion of NH3 and N2 selectivity by increasing the acid sites of the sample. According to the C, N balance data and FT-IR results, when the temperature was below 30 °C, the removal of HCN over Cu8Mn2/CeO2 was mainly by chemisorption and the HCN breakthrough behaviors corresponded to the Yoon and Nelson's model. When temperature was above 120 °C, the HCN was totally removed by catalytic hydrolysis and catalytic oxidation.

| S-EPMC8695306 | biostudies-literature

Bifunctional Mesoporous Carbon Nitride: Highly Efficient Enzyme-like Catalyst for One-pot Deacetalization-Knoevenagel Reaction.

Project description:Recently, mesoporous carbon nitride (MCN) has aroused extensive interest for its potential applications in organocatalysis, photo- and electrochemistry and CO2 capture. However, further surface functionalization of MCN for advanced nanomaterials and catalysis still remains very challenging. Here we show that acidic carboxyl groups can be smoothly introduced onto the surface of well-ordered MCN without annihilation between the introduced acid groups and MCN's inherent basic groups through a facile UV light oxidation method. The functionalization generates a novel bifunctional nanocatalyst which offers an enzyme-like catalytic performance in the one-pot deacetalization-Knoevenagel reaction of benzaldehyde dimethylacetal and malononitrile with 100% conversion and more than 99% selectivity due to the cooperative catalysis between the acid and base groups separated on the surface of the catalyst. The results provide a general method to create multifunctional nanomaterials and open new opportunities for the development of high efficient catalyst for green organic synthesis.

| S-EPMC4525375 | biostudies-literature

Efficient and reusable ordered mesoporous WO x /SnO2 catalyst for oxidative desulfurization of dibenzothiophene.

Project description:The oxidative desulfurization (ODS) of organic sulfur compounds over tungsten oxide supported on highly ordered mesoporous SnO2 (WO x /meso-SnO2) was investigated. A series of WO x /meso-SnO2 with WO x contents from 10 wt% to 30 wt%, were prepared by conventional wet impregnation. The physico-chemical properties of the WO x /meso-SnO2 catalysts were characterized by X-ray diffraction (XRD), N2 adsorption-desorption isotherms, electron microscopy, Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, and the temperature-programmed reduction of hydrogen (H2-TPR). The characterization results indicated that these catalysts possessed mesoporous structures with uniform pores, high specific surface areas, and well-dispersed polyoxotungstate species on the surface of meso-SnO2 support. The ODS performances were evaluated in a biphasic system (model oil/acetonitrile, S initial = 2000 ppm), using H2O2 as an oxidant, and acetonitrile as an extractant. Dibenzothiophene (DBT) in the model oil was removed completely within 60 min at 50 °C using 20 wt% WO x /meso-SnO2 catalyst. Additionally, the effect of reaction temperature, H2O2/DBT molar ratio, amount of catalyst and different sulfur-containing substrates on the catalytic performances were also investigated in detail. More importantly, the 20 wt% WO x /meso-SnO2 catalyst exhibited 100% surfur-removal efficiency without any regeneration process, even after six times recycling.

| S-EPMC9037815 | biostudies-literature

Guanidinylated SBA-15/Fe3O4 mesoporous nanocomposite as an efficient catalyst for the synthesis of pyranopyrazole derivatives.

Project description:In this study, a novel mesoporous nanocomposite was fabricated in several steps. In this regard, SBA-15 was prepared by the hydrothermal method, next it was magnetized by in-situ preparation of Fe3O4 MNPs. After that, the as-prepared SBA-15/Fe3O4 functionalized with 3-minopropyltriethoxysilane (APTES) via post-synthesis approach. Then, the guanidinylated SBA-15/Fe3O4 was obtained by nucleophilic addition of APTES@SBA-15/Fe3O4 to cyanimide. The prepared nanocomposite exhibited excellent catalytic activity in the synthesis of dihydropyrano[2,3-c]pyrazole derivatives which can be related to its physicochemical features such as strong basic sites (presented in guanidine group), Lewis acid site (presented in Fe3O4), high porous structure, and high surface area. The characterization of the prepared mesoporous nanocomposite was well accomplished by different techniques such as FT-IR, EDX, FESEM, TEM, VSM, TGA, XRD and BET. Furthermore, the magnetic catalyst was reused at least six consequent runs without considerable reduction in its catalytic activity.

| S-EPMC8494731 | biostudies-literature

Hollow Mesoporous Fe2O3 Nanospindles/CNTs Composite: An Efficient Catalyst for High-Performance Li-O2 Batteries.

Project description:The design of mesoporous or hollow transition metal oxide/carbon hybrid catalysts is very important for rechargeable Li-O2 batteries. Here, spindle-like Fe2O3 with hollow mesoporous structure on CNTs backbones (Fe2O3-HMNS@CNT) are prepared by a facile hydrolysis process combined with low temperature calcination. Within this hybrid structure, the hollow interior and mesoporous shell of the Fe2O3 nanospindles provide high specific surface area and abundant catalytical active sites, which is also beneficial to facilitating the electrolyte infiltration and oxygen diffusion. Furthermore, the crisscrossed CNTs form a three-dimensional (3D) conductive network to accelerate and stabilize the electron transport, which leads to the decreasing internal resistance of electrode. As a cathodic catalyst for Li-O2 batteries, the Fe2O3-HMNS@CNT composite exhibits high specific capacity and excellent cycling stability (more than 100 cycles).

| S-EPMC6672713 | biostudies-literature

Synthesis of a Highly Stable Pd@CeO2 Catalyst for Methane Combustion with the Synergistic Effect of Urea and Citric Acid.

Project description:Making use of synergy between urea and citric acid, a core-shell Pd@CeO2 catalyst with spherical morphology was facilely synthesized by a hydrothermal method. The formation mechanism of the core-shell structure in the presence of citric acid and hydrogen peroxide was studied. Results showed that the Pd@CeO2 catalyst exhibited high catalytic activity in methane oxidation. Pd nanoparticles were well stabilized by CeO2 shell encapsulation, resulting in high stability of the catalyst. A high CH4 conversion of 99% was retained after 50 h on-stream reaction at 500 °C. Additionally, many tiny pores on the CeO2 shell surface were beneficial for the full contact between reactants and active components. Pd nanoparticles were highly dispersed inside the shell, improving the utilization efficiency of active components. The results also demonstrated that the Pd species in the catalyst existed in the form of oxidation state, mainly in PdO (ca. 66.6%), which played an essential part in methane combustion.

| S-EPMC6643508 | biostudies-literature