Fuel Cells
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2022
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IF 2.948
Yanqi Hao,Lin Ge,Siew Hwa Chan
Looking for non-noble metal catalysts with low cost, high activity, and high stability to replace platinum in oxygen reduction reaction (ORR) has aroused great concern. According to previous studies, Fe-N x /C material is one of the most promising non-noble metal catalysts for ORR. In this study, new Fe-N x /C material was synthesized by introducing CeO 2 and Fe 3 O 4 nanoparticles into a Fe-N x /C material derived from ZIF-8 as precursors. The new material was called CeO 2 -Fe 3 O 4 @Fe-N/C catalyst and the activity of the catalyst was found to be significantly improved in 0.1 mol L −1 KOH. The half-wave potential of CeO 2 -Fe 3 O 4 @Fe-N/C (0.892 V) is higher than that of Pt/C by 67 mV. In the stability test, the half-wave potential of CeO 2 -Fe 3 O 4 @Fe-N/C was only reduced by 4 mV after 5,000 cycles. The high performance is attributed to the introduction of CeO 2 and Fe 3 O 4 , which gives CeO 2 -Fe 3 O 4 @Fe-N/C enhanced electrocatalytic activity and long-term stability. This approach makes CeO 2 -Fe 3 O 4 @Fe-N/C a promising candidate for cathode catalysts in renewable energy conversion devices.
研究领域:
材料科学
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能源化学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2024
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IF 7.4
Hua Chai,Ze Zhang,Jie Sun,Mingjun Zhong,Mengxue Liu,Jing Li,Zihao Chen,Beini Gong,Qiaoling Xu,Zhujian Huang,Lihua Cui
This research investigates the synergistic enhancement of semiconductor catalysts through the incorporation of carbon quantum dots (CQDs) within CeO 2 -Fe 3 O 4 Type-II heterojunction photocatalysts. Subsequent to the successful synthesis of these modified photocatalysts, a thorough assessment of their catalytic performance is conducted. Notably, the introduction of CQDs results in a 21% increase in pollutant degradation capacity compared to unmodified heterojunctions, with a remarkable removal efficiency of 96% for the target pollutant TC. Comprehensive analyses employing electrochemical impedance spectroscopy (EIS), UV–vis spectroscopy, and photocatalytic experiments provide substantial evidence for the efficacy of CQDs in enhancing light absorption properties within the CeO 2 -Fe 3 O 4 heterojunction. This enhancement is attributed to a notable suppression of electron-hole pair recombination, facilitating the generation of reactive oxygen species (ROS) such as ·O 2 - and ·OH. This, in turn, the promotion of Ce 4+ /Ce 3+ and Fe 3+ /Fe 2+ cycles takes place, collectively enhancing the responsiveness of the photocatalyst to visible light. The photocatalysts demonstrate enduring catalytic and magnetic stability over five cycles, as indicated by the sustained high-performance retention. Detailed analysis using TOF-LC-MS has revealed two highly efficient degradation pathways for the for the target pollutant. The findings contribute valuable insights for advancing the performance of heterojunction photocatalysts.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Xiaoxue Yang,Kun Luo,Zhoujie Pi,Peng Shen,Puyu Zhou,Li He,Xiaoming Li,Qi Yang
A novel nanocomposite CeO 2 /Fe 3 O 4 /biochar (BC) was prepared using a straightforward, solvent-free mechanical ball milling method. Comparatively to the material prepared by chemical co-precipitation (77.14 %) and raw BC (33.64 %), CeO 2 /Fe 3 O 4 /BC prepared by ball milling achieved better tetracycline (TC) removal (94.35 %) under the optimal condition (TC concentration 10 mg·L -1 , catalyst dose 0.5 g·L -1 and pH 9.01). Ball milling not only reduced the particle size, but also increased the surface area of composite, which was favorable to the adsorption of TC on CeO 2 /Fe 3 O 4 /BC. Meanwhile, the number of oxygen-containing functional groups in as-prepared nanocomposite increased after ball milling, which could serve as the bridge of electron transfer to enhance TC degradation. Dissolved oxygen (DO) was activated by CeO 2 /Fe 3 O 4 /BC to produce reactive oxygen species (ROS) for the TC degradation. X-ray photoelectron spectroscopy (XPS) and electron spin resonance (ESR) characterization indicated that the enhanced oxygen activation should be attributed to the presence of Ce 4+ /Ce 3+ and Fe 3+ /Fe 2+ redox pairs and persistent free radicals (PFRs) in CeO 2 /Fe 3 O 4 /BC. Desorption experiments suggested that the adsorption and degradation induced by ball-milled CeO 2 /Fe 3 O 4 /BC were accounted for about 79.8 % and 20.2 % of total TC removal, respectively. This study revealed that the organic pollutants removal by BC-based nanocomposite is not alone contribution of the adsorption and the degradation behavior during this process should be concerned.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2025
·
IF 4.3
Zhuoqun Deng,Nianxi Wang,Yang Wang,Xujing Li,Haixiang Li,Dexun Zou,Yanping Liu
Due to the persistence and toxicity of PAHs, the accumulation of PAHs in soil causes environmental challenges. Utilizing nanoparticles to activate persulfate (PS) is an eco-friendly and cost-effective method for degrading PAHs. Herein, an advanced oxidation system with Fe 3 O 4 and CeO 2 loaded on BC as PS activators (Fe 3 O 4 -Ce@BC/PS) has been constructed, achieving a total removal of 89.34 % of PAHs from soil at 48 h of reaction at room temperature. Notably, High Resolution Transmission Electron Microscope analysis confirmed the presence of a CeO 2 -Fe 3 O 4 heterojunction, and Density functional theory calculations further revealed the key function of this structure. It reduced the adsorption energy of PS (−4.03 eV), thereby improving its utilization efficiency. In addition, during the reaction process, OH and SO 4 − as the main active species collaborated with 1 O 2 , O 2 − and electron transfer to degrade PAHs. In a word, the Fe 3 O 4 -Ce@BC/PS system developed in this study provided an effective solution to the problem of PAHs-contaminated soil.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Kamran Ashraf,Zebo Liu,Qamar uz Zaman,Muhammad Arshad,Waqas Qamar Zaman,Ali Shan,Junxiong Yu,Touseef ur Rehman,Yingping Zhuang,Meijin Guo,Ali Mohsin
Elicitation is a potent strategy to enhance secondary metabolite yield, and nanoparticle-mediated elicitation offers a compelling alternative to traditional methods. Carthamus tinctorius ( C. tinctorius ) is rich in bioactive chlorogenic acids (CGAs) within its suspension cells. However, the mechanism by which doped nanoparticles (NPs) stimulate the CGAs biosynthesis in the cells remains unclear. Therefore, this study first elucidated the synthesis and characterization of selenium (Se)-doped CeO 2 @Fe 3 O 4 NPs and then explored their regulatory effect and mechanism for the CGAs biosynthesis in C. tinctorius cells. Material characterization via TEM, XPS, XRD, and EDX analysis confirmed the successful synthesis of selenium-dopped CeO 2 @Fe 3 O 4 nanocomposite. Fe 3 O 4 , CeO 2 , Fe 3 O 4 @CeO 2 , and selenium-dopped CeO 2 @Fe 3 O 4 NP treatments all promoted the biosynthesis of CGAs in the cells. Notably, the group treated with 15 mg L -1 selenium-dopped CeO 2 @Fe 3 O 4 NPs showed best effect (37.04 mg g −1 , 1.92 times that of control). Finally, metabolome and transcriptome profiling revealed the differential alterations in the content of 45 primary metabolites and differential expression of 83 CGA biosynthesis-related genes. This suggested that selenium-doped CeO 2 @Fe 3 O 4 NPs up-regulated the expression of CGA biosynthesis-related genes, and consequently enhanced CGAs accumulation in the cells. This study provides the first evidence that selenium-doped CeO 2 @Fe 3 O 4 acts as nano-elicitors for the biosynthesis of CGAs.
研究领域:
植物学
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纳米生物学
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代谢组学
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转录组学
✓ 已验证
DOI
高影响因子
RENEWABLE ENERGY
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2021
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IF 8.001
Yanan Wei,Xin Li,Yunlei Zhang,Yongsheng Yan,Pengwei Huo,Huiqin Wang
Wide-light absorption performance and efficient carrier separation ability are the necessary conditions for excellent photocatalytic materials. In this research, g-C 3 N 4 QDs (CN QDs) and Au nano-particles (NPs) co-modified CeO 2 /Fe 3 O 4 micro-flowers (MFs) photocatalyst (CACeF) has been prepared. CO 2 photoreduction experiments showed that the composite had obviously enhanced photoreduction activity and photocatalytic stability. The yields of CO and CH 4 over it as catalyst in 4 h is about 5 and 8 times greater than that of pure CeO 2 . Photoelectrochemical tests showed that the heterojunction between CN QDs and Au NPs can greatly improve the carrier separation ability and the light-utilization efficiency of photocatalysts. Besides, the excellent electronic transmission performance of Au NPs provided a specific channel for the electron transmission, and the strong local surface plasmon resonance (LSPR) of Au NPs resulted in a lot of hot-electrons can directly take part in the CO 2 photoreduction. The synergistic effect between CN QDs and Au NPs can further enhance the photocatalytic activity of the photocatalyst. Fe 3 O 4 QDs can ensure the effective recovery and reuse of the composite without affecting the photocatalytic performance of composite. Finally, a potential photoreduction mechanism of CN QDs and Au NPs co-modified CeO 2 /Fe 3 O 4 MFs photocatalyst were discussed in total.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
KOREAN JOURNAL OF CHEMICAL ENGINEERING
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2025
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IF 3.2
Rao Qian,Li Hui-qiang,Yang Ping,Guo Ziou
Mo 2 C@Fe 3 O 4 and three kinds of MO 2 -doped Mo 2 C@Fe 3 O 4 were successfully fabricated as the Mo 2 C@TiO 2 @Fe 3 O 4 , Mo 2 C@MoO 2 @Fe 3 O 4 and Mo 2 C@CeO 2 @Fe 3 O 4 particles for the degradation of 2-methyl-4-isothiazolin-3-one and 1-hydroxy-1,1-diphosphonoethane in a three-dimensional electro-Fenton system. The catalyst particles showed an enhancement for the catalytic activity in the system. Furthermore, the Mo 2 C@CeO 2 @Fe 3 O 4 particles exhibited superior activity for 2-methyl-4-isothiazolin-3-one and 1-hydroxy-1,1-diphosphonoethane degradation compared to the other two particles. Based on the characterization of the synthesized particles, leaching concentration of Fe 2+ , generation of \({H}_{2}{O}_{2}\) , \(\bullet OH\) , \({O}_{2}^{\bullet -}\) , the reasons for the difference in pollutant degradation performance among the three type particles were comprehensively analyzed. At last, some important experimental parameters, such as particles dosage, current density and aeration intensity, which would obviously affect MIT and HEDP degradation performance were studied. Using the Mo 2 C@CeO 2 @Fe 3 O 4 as catalytic particles, optimal 2-methyl-4-isothiazolin-3-one and 1-hydroxy-1,1-diphosphonoethane degradation rates were 97.2% and 73.8% with 0.5 g of particle dosage, 97.22% and 73.75% with 300 mA of current density, and 97.28% and 73.71% with 0.1 L min −1 of aeration intensity.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
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2024
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IF 6.7
Sitong Liu,Shengli Niu,Hewei Yu,Kuihua Han,Sunwen Xia,Zihao Yang,Yue Zheng,Yujiao Zhang,Yanan Hao,Abulikemu Abulizi
The current transesterification for biodiesel is normally conducted with heat input and the resource is required to remove the contained water, which is complicated and costly. The novel magnetic catalyst of the bimetallic oxides of CeO 2 and Fe 3 O 4 supported on the hierarchical pore ZSM-5 was prepared and used for the biodiesel production through transesterification of palm oil with methanol under the electrolytic assistance. The prepared catalysts were characterized by SEM-EDS, TEM, FTIR, XRD, CO 2 /NH 3 -TPD, N 2 adsorption–desorption and VSM, etc. The loaded cerium stimulated the particles growth and abundant catalytic active sites were obtained due to the coral-like structure and they were beneficial for transesterification. The presence of both acidic and basic sites guaranteed the strong catalytic capability of the CeO 2 /ZSM-5@Fe 3 O 4 catalyst. Under the optimized transesterification condition of the catalyst dosage of 3 wt%, methanol to oil molar ratio of 18:1, reaction time of 2.5 h, electrolysis voltage of 40 V, presence of 2 % wt/wt of water added and reaction temperature of 25 ℃, the FAME yield of approximately 95 % was achieved. Also, the catalyst showed an acceptable reusability, where the FAME yield of 79 % was obtained after fourth reused cycle. In conclusion, the water in the resource promotes the electrolytic transesterification to occur efficiently at the room temperature.
研究领域:
化学工程
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可再生能源
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催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2021
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IF 7.963
Xiangcheng Shan,Yumeng Zhao,Shufeng Bo,Liyu Yang,Zuoyi Xiao,Qingda An,Shangru Zhai
Phosphorus (P) has brought a series of environmental problems while benefiting mankind. To reclaim phosphorus from wastewater efficiently and conveniently, a novel magnetic adsorbent with aminated lignin/CeO 2 /Fe 3 O 4 composites (AL-NH 2 @Fe 3 O 4 -Ce) possessing a high affinity to phosphate and easily separated from aqueous solutions was developed in this work. The characterization results revealed that Fe and Ce elements have been doped into the aminated lignin successfully. Batch experiment results convinced that the maximum phosphate adsorption capacity of AL-NH 2 @Fe 3 O 4 -Ce was 183.72 mg P/g at pH = 3, which was roughly 4.5 times greater than aminated lignin and 8.5 times greater than cerium oxide, respectively. The adsorption isotherm was fitted well by the Langmuir model, and the adsorption kinetics was in line with the pseudo-second-order model. The adsorption thermodynamics indicated the adsorption process was spontaneous and naturally exothermic. Additionally, AL-NH 2 @Fe 3 O 4 -Ce exhibited high selectivity towards phosphate over common coexisting anions (Cl − , NO 3 − , HCO 3 − , SO 4 2− and F − ). After five consecutive cycles, the adsorption performance of AL-NH 2 @Fe 3 O 4 -Ce decreased by only 16% compared with the fresh adsorbent, indicating that AL-NH 2 @Fe 3 O 4 -Ce exhibited excellent recycling ability. The results of XPS analysis and batch experiments showed that the possible mechanisms were electrostatic attraction and inner-sphere complexation. The tailored interfacial chemistry affinity to phosphate as well as endowed magnetic property reveled AL-NH 2 @Fe 3 O 4 -Ce could be adopted as an up and coming adsorbent in phosphate removal process.
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
CATALYSIS LETTERS
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2024
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IF 2.3
Ren Zongli,Zhao Zhongwei,Ma Xin,Zhang Weiwei
Construction of multi-interface contact step-scheme (S-scheme) photocatalyst is a promising pathway to achieve high-electron transfer efficiency for photodegradation estrone and congo red. In this paper, g-C 3 N 4 is chosen as the main photocatalyst, CeO 2 nanosheet with the unique Ce 4+ → Ce 3+ conversion performance and Fe 3 O 4 -Reduced graphene oxide are loaded onto the g-C 3 N 4 surface to bulid 2D-2D magnetic photocatalyst. The 2D–2D magnetic photocatalyst structure imparts reusability by magnetic retrieval and at the same time Fe 3 O 4 -Reduced graphene oxide acts as an efficient host for g-C 3 N 4 /CeO 2 composite photocatalyst. The photocatalytic performance is examined using etsrone and congo red. Photodegradation studies show the CeO 2 /g-C 3 N 4 / Fe 3 O 4 - Reduced graphene oxide a composite catalyst can degrade 71% of estrone, 92% of congo red and 89% phenanthrene, Free radical scavenger test shows superoxide and hydroxyl radical species play a major role in the degradation. Furthermore, it is demonstrated that the magnetic CeO 2 /g-C 3 N 4 / Fe 3 O 4 -Reduced graphene oxide possesses strong antibacterial properties against Proteus mirabilis and Escherichia coli. A three-factor-three-level Box–Behnken design (BBD) was selected to optimize three greatly influential parameters: light irradiation time (min), The quality of photocatalyst(mg) and pollution concentration(ppm) by response surface methodology. It is expected that CeO 2 /g-C 3 N 4 / Fe 3 O 4 - Reduced graphene oxide can be used as a 2D–2D magnetic photocatalyst for to achieve its valorization, which have very broad development prospects in the field of environmental remediation or catalysis. Graphical Abstract
研究领域:
环境科学
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材料科学
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化学工程
✓ 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）