APPLIED CATALYSIS B-ENVIRONMENTAL
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2024
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IF 20.2
Fang Dong,Yu Meng,Weitong Ling,Weigao Han,Weiliang Han,Xiaona Li,Zhicheng Tang
Development of low-cost noble Pt-based catalyst with superior catalytic performance is a challenge to achieve its application in VOCs catalytic oxidation. Although the single atom provides a strategy to design and develop highly efficient heterogeneous catalysts that simultaneously maximizes the utilization of precious metal atoms, the stability of single atom catalysts is not satisfactory as a result of its high atomic surface energy. Here we construct a Pt 1 @CeO 2 single atom catalyst (SAC) with excellent catalytic activity for benzene catalytic combustion (T 90 = 212 °C) and low precious metal Pt loading, and even displaying an outstanding thermal stability and water resistance under the harsh conditions of 30,000 mL/g/h and 2000 ppm benzene. This Pt 1 @CeO 2 catalyst was obtained by in situ domain limited encapsulation of Pt species in Ce-MOFs nanocages during the solvothermal reaction process. It is observed that lots of oxygen vacancies were created by the dislocation and phase transition of CeO 2 to provide abundant sites for anchoring single atomic Pt, which can be localized and anchored firmly to oxygen vacancies, thus forming the highly stable Pt single atom. The atomically dispersed Pt is capable of improving the catalytic activity by forming Pt-O band. The good water resistance may be ascribed to the confined Pt single atom into oxygen vacancies of CeO 2 support to form strong metal-support interaction (SMSI), and the PtO x nanoparticles would be easy to aggregate deactivation under water vapor conditions. It is a simple and universal strategy to prepare Pt SAC via the inherently confined space of MOFs nanocages formed by coordination of organic ligands and metal ions, which benefits from the functional modification of ethylene glycol in MOFs self-assembly reaction.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2021
·
IF 19.503
Guixian Deng,Guifang Zhang,Xing Zhu,Qingjie Guo,Xiangbiao Liao,Xi Chen,Kongzhai Li
Reduction of CO 2 in presence of oxidative impurity ( e.g. , O 2 ) is more promising than utilization of pure CO 2 due to skyrocketing cost for purification of captured CO 2 from air or industrial exhaust gas. In this work, Ni-based catalysts are modified by CeO 2 and ZrO 2 to suppress negative effect of O 2 on reforming of CO 2 with methane, which show high CH 4 conversion (97 %) and CO 2 conversion (95 %) at 750 °C and can maintain high CO 2 conversion even with high O 2 content. The physicochemical characterizations on fresh and spent catalysts show that the interaction among Ni, CeO 2 and ZrO 2 results in well dispersion of smaller Ni particles, even after long-term testing. In situ DRIFTS results show that Ni/CeO 2 -ZrO 2 -SiO 2 catalyst shows advantage to activate CH 4 to generate active CH 3 *, promoting the formation of CO, and the CeO 2 -ZrO 2 solid solution improves the CO 2 adsorption, thereby reducing the competitive effect of CO 2 and O 2 .
研究领域:
化学工程
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催化材料
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 34
·11897-11903
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IF 4
Ying Liu,Baoteng Li,Sailong Xu,Ying Guo
In this paper, highly dispersed hierarchical coral spheres of CeO2/ZnO have been constructed through a facile template-free hydrothermal strategy, followed by an annealing treatment. The resulting coral spheres exhibit enhanced activity for acetone sensing compared with CeO2 or ZnO as well as excellent cyclability and long-term stability. At the optimum working temperature of 245 °C, by controlling the ratio of Ce/Zn, the highest response of the coral spheres towards 100 ppm acetone is up to 145, which is about 5.5 times that of ZnO coral spheres. The significantly improved gas sensing activity may be ascribed to the well-dispersed and assembled CeO2 nanoparticles on the surface of ZnO coral spheres and the heterojunctions between CeO2 and ZnO, which produced abundant oxygen vacancies in the CeO2/ZnO coral spheres.
研究领域:
材料科学
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传感器技术
✓ 已验证
DOI
PubMed
高影响因子
FUEL
·
2023
·
IF 7.4
Xiushuai Guan,Shanbiao Jin,Le Liu,Xiya Zhao,Xiaochao Zhang,Changming Zhang,Zhong Li,Caimei Fan
The utilization of oxygen vacancies to modulate the surface properties of catalysts is a powerful way to enhance catalytic activity. In this work, the doping effect of Bi 3+ on the performance of CeO 2−δ (Ce x Bi 1−x O 2−δ ) hybrid nanorods with rich oxygen vacancies for the photo-thermal synthesis of dimethyl carbonate (DMC) from CO 2 /CH 3 OH (140 ℃, 1.6 MPa, 4 h) is systematically investigated. It is found that Ce 0.9 Bi 0.1 O 2−δ exhibits the best catalytic performance, achieving a photo-thermal yield of 3.13 mmol∙g −1 without any dehydrating agent (1.14 times compared to thermal catalysis). It turns out that regulating the concentration of Bi 3+ ions not only modifies the oxygen vacancy content, but also improves the light harvesting efficiency. Moreover, a series of characterization techniques, such as X-ray photoelectron spectroscopy, Raman spectrometer and electron paramagnetic resonance are employed to analyze and verify that the asymmetric oxygen vacancies are conducive to the improvement in the CO 2 adsorption-activation. Finally, a possible reaction mechanism model of Bi 3+ doping on CeO 2−δ for the photo-thermal synthesis of DMC from CO 2 and CH 3 OH is proposed. This work provides a practical approach to catalyst surface engineering design.
研究领域:
材料科学
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催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2024
·Vol. 14
·期 14
·10056-10069
·
IF 3.9
Fengqin Tang,Hui Bai,Yahui Chen,Chunhui Shi,Dong Wang,Yaju Zhang,Wenyuan Liu,Ling Yang,Libing Hu
The requirement for the removal of phosphorus (P) from wastewater has become progressively stringent, therefore, it is essential to remove low-concentration phosphate from secondary effluents through a tertiary treatment. One of the biggest challenges in removing phosphate from wastewater is the development of low-cost, green, and pollution-free adsorbents. In this study, novel, eco-friendly and low-cost CeO2 nanosphere modifying CoAl-LDH nanosheets (CoAl-LDH/CeO2) were successfully fabricated using a classical hydrothermal strategy. The microstructure and morphology of CoAl LDH/CeO2 were characterized using SEM, TEM, FTIR, XRD, TG, XPS, and BET techniques. The performance of the P adsorption from water for CoAl-LDH/CeO2 was investigated. The influences of adsorption parameters, such as adsorbent dosage, pH, phosphate concentration, adsorption time, and experimental temperature, were investigated through batch adsorption experiments. The batch adsorption experiments showed that the P removal by CoAl-LDH/CeO2 could reach 93.4% at room temperature within 60 minutes. CoAl-LDH/CeO2 showed ultrafast and high-efficiency adsorption for low concentration P contaminated wastewater. Pseudo-second order model exhibited better fitting with the kinetics of the phosphate adsorption, while the Freundlich model well-described the isotherm results (R2 > 0.999). Although Cl−, NO3−and SO42− coexisted in the solution, CoAl-LDH/CeO2 still possessed favourable selectivity for phosphates. More importantly, the adsorption capacities of CoAl-LDH/CeO2 retained over 85% after five cycles. Therefore, the low cost and sustainable utilization of CoAl-LDH/CeO2 for the phosphate removal from secondary effluent with phosphate at a low concentration highlights its potential application to alleviate eutrophication.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Sciences
·
2024
·
IF 5.9
Xuan Liang,Jin Zhang,Juntai Tian,Zenghua Xie,Yue Liu,Peng Liu,Daiqi Ye
Herein, three supported catalysts, CuO/Al 2 O 3 , CeO 2 /Al 2 O 3 , and CuO-CeO 2 /Al 2 O 3 , were synthesized by the convenient impregnation method to reveal the effect of CeO 2 addition on catalytic performance and reaction mechanism for toluene oxidation. Compared with CuO/Al 2 O 3 , the T 50 and T 90 (the temperatures at 50% and 90% toluene conversion, respectively) of CuO-CeO 2 /Al 2 O 3 were reduced by 33 and 39 °C, respectively. N 2 adsorption-desorption experiment, XRD, SEM, EDS mapping, Raman, EPR, H 2 -TPR, O 2 -TPD, XPS, NH 3 -TPD, Toluene-TPD, and in-situ DRIFTS were conducted to characterize these catalysts. The excellent catalytic performance of CuO-CeO 2 /Al 2 O 3 could be attributed to its strong copper-cerium interaction and high oxygen vacancies concentration. Moreover, in-situ DRIFTS proved that CuO-CeO 2 /Al 2 O 3 promoted the conversion of toluene to benzoate and accelerated the deep degradation path of toluene. This work provided valuable insights into the development of efficient and economical catalysts for volatile organic compounds.
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER TESTING
·
2024
·
IF 5
Jiajia Zeng,Chongxian He,Xinna Bai,Cijun Shuai,Hao Pan
Photodynamic therapy (PDT) has great potential for tumor therapy because of its non-invasive and high selectivity. However, the therapeutic effect of PDT is critically restricted by hypoxia and glutathione (GSH) overexpression in the tumor microenvironment (TME). In this work, CeO 2 with catalase and peroxidase dual enzyme activities was loaded on Ti 3 C 2 nano-sheet, and the nanosystem was then introduced in poly-L-lactic acid (PLLA) and prepared into bone scaffold using selective laser sintering technology. Specifically, CeO 2 alleviates hypoxia through its catalase enzyme activity, which promotes the continuous photodynamic process. CeO 2 also consumes over-expressed GSH through its redox reaction and amplifies the oxidative stress in TME, thus improving the curative effect of PDT. On the other hand, the photothermal effect of scaffold can not only generate heat to kill tumor cells, but also enhance the activity of nanoenzyme, and the catalase activity enhanced by photothermal effect is fed back to PDT, forming a two-way promotion. The results indicated that the concentration of oxygen in PLLA/Ti 3 C 2 -CeO 2 scaffold group was 9.76 mg/L higher, and the concentration of singlet oxygen ( 1 O 2 ) and hydroxyl radical (·OH) was respectively increased by 60% and 170%, compared with the PLLA/Ti 3 C 2 scaffold. Moreover, the PLLA/Ti 3 C 2 -CeO 2 scaffold showed a higher GSH consumption rate, indicating that it could consume the overexpressed GSH. Therefore, the Ti 3 C 2 nano-sheet loaded with CeO 2 could combine the dual enzyme activities, photodynamic and photothermal effect to enhance the tumor therapy with a tumor growth inhibitory effect of approximately 88.8%. In summary, introducing the Ti 3 C 2 nanosystem loaded with nanozyme into PLLA scaffold is a promising strategy to develop bone scaffold with multimodal anti-tumor function.
研究领域:
生物医学工程
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肿瘤治疗学
✓ 已验证
产品关联
DOI
高影响因子
CEMENT AND CONCRETE RESEARCH
·
2024
·
IF 10.9
Haosen Ma,Yanjie Tang,Wei Chen,Qiu Li
The immobilisation mechanism of Pu(IV) by Portland cement-based material is not well understood. This study aims to reveal the immobilisation mechanism and occurrence status of Ce(IV) (chemical analogue of Pu(IV)) in Portland cement paste. The addition of Ce(NO 3 ) 4 first slightly retarded then accelerated the early-age hydration of Portland cement , thereby resulting in an increase of compressive strength by 29 %. The main contributor to immobilisation of Ce is Portland cement rather than zeolite . The hydration products were not altered by Ce(NO 3 ) 4 addition, whereas the hydration degree and mean chain length of C-(Al/Ce)-S-H increased. Over 99.99 % of Ce was immobilised by synthesised C-S-H. A analysis of the synthesised C-S-H confirmed the formation of C-Ce-S-H, where Ce tetrahedra took the bridging site of silicate chain of C-Ce-S-H. Nano-crystalline CeO 2 grains were identified, which intermixed with C-Ce-S-H. Approximately 90 % of Ce were immobilised by C-Ce-S-H, and the rest exist as nano-crystalline CeO 2 grains.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2022
·Vol. 46
·期 7
·9733-9747
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IF 4.672
Yingwei Xiong,Jinglan Wang,Min Jin,Xiaohong Wang
Summary Fe 2 O 3 is recognized as a promising oxygen carrier, but the susceptibility to sintering over the redox cycles limits its application. Although depositing Fe 2 O 3 on CeO 2 can simultaneously improve the activity and durability, the formation of CeFeO 3 will decrease the oxygen capacity and thus the efficiency of chemical looping water-gas shift reaction. Doping foreign elements can effectively mitigate the reaction between Fe 2 O 3 and CeO 2 and improve redox reactivity. This work employs Gd 3+ and Sm 3+ as doping elements and investigates the doping effect on hydrogen generation of Fe 2 O 3 /CeO 2 in water-gas shift with chemical looping. The characterizations demonstrate that both Gd and Sm are incorporated into the lattice of CeO 2 and increase the oxygen defect concentration, which boosts the redox reactivities. In addition, the interaction between the dopants and CeO 2 promotes the reduction depth by suppressing the solid reaction between Fe 2 O 3 and CeO 2 and improves the reoxidation reaction between reduced oxygen carriers with steam. As a result, Fe 2 O 3 /Ce 0.8 Sm 0.1 Gd 0.1 O 1.9 shows a high hydrogen yield (8.73 mmol.g −1 ) and hydrogen production rate (582.2 μmol.g −1 .min −1 ), which is 1.67 times higher than that of Fe 2 O 3 /CeO 2 . The performance remains stable over 40 cycles. The introduction of foreign cations may provide an effective method and significantly impact the oxygen carrier design.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2019
·
IF 2.846
Lei Chen,Ding Wang,Jiadao Wang,Duan Weng,Li Cao
The CeO 2 -TiO 2 (CeTi) and CeO 2 /WO 3 -TiO 2 (CeWTi) catalysts were prepared by sol-gel method. The as-prepared catalysts were hydrothermally treated at 760 °C for 48 h in air containing 10 vol% H 2 O to obtain the hydrothermal aged catalysts. The sulfur aged catalysts were treated at 400 °C with 100 ppm SO 2 , 10% water vapor, air balance for 48 h and catalysts. The powder X-ray diffraction (XRD) and Raman results indicate that the crystallization of hydrothermal aged catalysts is more serious than sulfur aged catalysts. In addition, tungsten species can stabilize the CeTi catalyst from grain growth. According to the results of in situ diffuse reflectance infrared Fourier transform spectra (DRIFTS), temperature-programmed desorption of ammonia (NH 3 -TPD), H 2 temperature-programmed reduction (H 2 -TPR) and ammonia oxidation , the aging process leads to loss of surface area, redox properties, surface acidities and surface ceria concentration, especially for the hydrothermal aging. The NH 3 -NO/NO 2 SCR performances of sulfur aged catalysts are better than that of hydrothermal aged catalysts. Compared with CeTi catalyst, the addition of tungsten inhibits the crystallization of catalyst. So that more acid sites and active sites are retained. This is also the reason why tungsten addition improves the NH 3 -NO/NO 2 SCR performance of CeTi catalyst.
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2022
·Vol. 12
·期 5
·509
·
IF 4.501
Chi Li,Yongfu Lian,Qin Zhou
The degradation of a high concentration of organic pollutants has long been a challenge to water restoration, and the development of electro-Fenton catalysis offers a practical approach to solving this problem. In this study, a novel electro-Fenton catalyst, activated fullerene soot-loaded NiO-doped CeO2(0.4(0.4NiO-CeO2)-AFS) nanoparticles, was prepared through the impregnation of 0.4NiO-CeO2particles and activated fullerene soot (AFS). When applied for the degradation of 200 mg/L of tetracycline, this catalyst demonstrated a degradation rate as high as 99%. Even after 20 cycles, the degradation rate was more than 80%. Moreover, it was concluded that AFS could initiate the synergistic effect between Ni and Ce dual active centers in the degradation of tetracycline; this can be ascribed to the extremely large specific surface area of AFS.Keywords:fullerene soot;NiO-doped CeO2;tetracycline;degrading efficiency;electro-Fenton
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
·
2023
·
IF 3.9
Wanyi Tao,Bo Zhang,Luxia Yin,Xiao Teng,Zhang Wen,Zekai Zhang,Wensheng Ning
Fabrication of adsorbent can play an important role in the adsorption desulfurization technology as a most promising deeply desulfurization technology. Ag 2 O/CeO 2 /SiO 2 aerogel composites were synthesized, where the easy oxidation of Ce 3+ into Ce 4+ was realized by adding hydrogen peroxide, and were utilized to remove thiophenics from model fuels and aromatics. Compared with Ag 2 O/SiO 2 and CeO 2 /SiO 2 , the adsorption uptake and solvent washing regeneration performance of Ag 2 O/CeO 2 /SiO 2 for thiophene was obviously enhanced, and the adsorption selectivity for thiophene in the presence of aromatics was relatively close to CeO 2 /SiO 2 , attributed to that Ag 2 O/CeO 2 /SiO 2 adsorbed thiophenics via the π-Ag + complexation and S-Ce bonding, where the latter was main interaction. However, there was no synergistic interaction between Ag and Ce species acted as adsorption sites in the Ag 2 O/CeO 2 /SiO 2 , which could be supported by that the chemical state of Ag and Ce in Ag 2 O/CeO 2 /SiO 2 was consistent with corresponding one in Ag 2 O/SiO 2 and CeO 2 /SiO 2 , respectively. Among Ag 2 O/CeO 2 /SiO 2 aerogel composites with different molar ratios of Si/Ce, Ag 2 O/CeO 2 /SiO 2 -50 performed the best, its adsorption uptake for thiophene, benzothiophene and dibenzothiophene from model fuels arrived at 20.4, 21.8 and 27.2 mg-S/g ads , respectively. Langmuir and Freundlich adsorption isotherm models, the pseudo-second-order kinetic model could well describe the adsorption of thiophenics over Ag 2 O/CeO 2 /SiO 2 -50.
研究领域:
化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）