APPLIED CATALYSIS B-ENVIRONMENTAL
·
2019
·
IF 14.229
Yibin Bu,Yafeng Chen,Guiming Jiang,Xinmei Hou,Shun Li,Zuotai Zhang
To design an efficient catalyst for HCHO oxidation, it requires good understanding of the correlation between structural properties of catalyst and the reaction mechanism. We investigated performance of commercial CeO 2 (CeO 2 -C) and nanorod CeO 2 (CeO 2 -R) and the corresponding Au/CeO 2 catalysts in HCHO oxidation. Reactivity tests showed that Au/CeO 2 -R is highly efficient and stable in HCHO oxidation at room temperature, which is attributed to the highly active Au-CeO 2 -R interface. The strong interaction between Au and CeO 2 -R greatly promotes the creation of oxygen vacancies and Au 3+ near the interface, which promotes the formation of formate. The conversion of formate can follow both a decomposition and a direct oxidation pathway, which is remarkably enhanced by the coexistence of Au 3+ and oxygen vacancies. In addition, formate accumulation and Au particles aggregation led to deactivation. The presence of humidity promotes the oxidation of formate, which improves the reactivity and stability of Au/CeO 2 in HCHO oxidation.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Dong Liu,Feiyang Hu,Yue Yan,Runping Ye,Xiaohan Chen,Bingying Han,Zhang-Hui Lu,Li Zhou,Gang Feng,Rongbin Zhang
CO oxidation is the primary approach for eliminating CO from incomplete combustion, and the catalytic performance is dependent on the structure of catalysts. Herein, to explore the structure promotion in the CO oxidation reaction, polymethyl methacrylate was synthesized as the hard template to fabricate the three-dimensional ordered microporous (3DOM) Au/CeO 2 and compared the catalytic performance with the Au/CeO 2 rod catalyst. The 3DOM Au/CeO 2 catalyst could realize complete CO oxidation at 90 °C while 110 °C for Au/CeO 2 rod catalyst. The 3DOM Au/CeO 2 catalyst also showed outstanding stability for 60 h reaction. The achieved high performance could be attributed to the pore structures and the better metal-support interaction that facilitates abundant oxygen vacancies . Additionally, the Au distribution and oxygen vacancies promoted by the macropores structures were discovered using a series of characterizations. This work highlights the promotion of oxygen vacancies and metal-support interaction by 3DOM structure in CO oxidation reaction.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2023
·
IF 2.8
Chen Yao,Li Shuyue,Li Yuchao,Zheng Yanxia,Zuo Cuncun,Ge Tingting,Xu Rui,Huang Haofei,An Jiutao
Nano-Au particles are commonly used as an active component in oxidation esterification reactions. To inhibit the agglomeration of nano-Au particles, a series of highly stable Au@CeO 2 /MnO x core–shell structured catalysts were synthesized using inverse microemulsion technology for the oxidative esterification to prepare methyl methacrylate (MMA). The core–shell structured catalysts were prepared by using two different surfactants (CTAB and CO-520) and adjusting the molar ratio of water to oil (ω). XRD, Raman, N 2 adsorption, ICP−MS, TEM, UV–vis, FT-IR, XPS, and H 2 -TPR were applied to characterize the samples. The nano-Au particles were encapsulated by CeO 2 , forming a core–shell structure confirmed with TEM. The Au@CeO 2 /MnO x -C-ω = 10 catalyst prepared with CTAB as the surfactant has the best activity. The Au@CeO 2 /MnO x -C-ω = 10 catalyst has the highest hydrogen consumption and Ce 3+ content, indicating that the catalyst has the strongest interaction among Ce, Au, and Mn and more active oxygen. Active oxygen is beneficial to methanol activation and hemiacetal dehydrogenation, accelerating the formation of esters. The active oxygen content, Ce 3+ content, and H 2 consumption were correlated with the catalytic performance positively. After the catalyst was reused 10 times, the activity remained unchanged and the Au nanoparticles did not agglomerate due to the core–shell structure. Graphical Abstract
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS COMMUNICATIONS
·
2019
·
IF 3.674
Bowen Lu,Fengjiao Quan,Zheng Sun,Falong Jia,Lizhi Zhang
Photothermal reverse-water-gas-shift is realized with high conversion rate and selectivity of CO in the case of Au/CeO 2 catalyst. Moreover, photothermal reaction rate is much higher (>10 times) than that performed under thermal condition. As indicated by the results of in-situ infrared spectroscopy and kinetic experiments, the special role of light is found to be related with the promotion of hydrogen-splitting step. The robust Au/CeO 2 catalyst exhibits stable activity and CO selectivity under long-term light irradiation. It is expected that the combination of catalysts and light may afford new perspectives for the CO 2 hydrogenation.
研究领域:
化学工程
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Nanoscale Horizons
·
2023
·Vol. 8
·期 6
·812-826
·
IF 9.7
Junqing Ye,Meizan Jing,Yu Liang,Wenjin Li,Wanting Zhao,Jianying Huang,Yuekun Lai,Weiyu Song,Jian Liu,Jian Sun
Exploring eco-friendly and cost-effective strategies for structure engineering at the nanoscale is important for boosting heterogeneous catalysis but still under a long-standing challenge. Herein, multifunctional polyphenol tannic acid, a low-cost natural biomass containing catechol and galloyl species, was employed as a green reducing agent, chelating agent, and stabilizer to prepare Au nanoparticles, which were dispersed on different-shaped CeO2 supports (e.g., rod, flower, cube, and octahedral). Systematic characterizations revealed that Au/CeO2-rod had the highest oxygen vacancy density and Ce(III) proportion, favoring the dispersion and stabilization of the metal active sites. Using isopropanol as a hydrogen-transfer reagent, deep insights into the structure–activity relationship of the Au/CeO2 catalysts with various morphologies of CeO2 in the catalytic nitrobenzene transfer hydrogenation reaction were gained. Notably, the catalytic performance followed the order: Au/CeO2-rod (110), (100), (111) > Au/CeO2-flower (100), (111) > Au/CeO2-cube (100) > Au/CeO2-octa (111). Au/CeO2-rod displayed the highest conversion of 100% nitrobenzene and excellent stability under optimal conditions. Moreover, DFT calculations indicated that nitrobenzene molecules had a suitable adsorption energy and better isopropanol dehydrogenation capacity on the Au/CeO2 (110) surface. A reaction pathway and the synergistic catalytic mechanism for catalytic nitrobenzene transfer hydrogenation are proposed based on the results. This work demonstrates that CeO2 structure engineering is an efficient strategy for fabricating advanced and environmentally benign materials for nitrobenzene hydrogenation.
研究领域:
催化化学
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2015
·Vol. 50
·期 19
·6339-6348
·
IF 2.371
He Beibei,Zhao Qingguo,Zeng Zhigang,Wang Xiaohong,Han Sheng
Au@CeO 2 core–shell nanostructure catalysts were synthesized by hydrothermal reaction method. The effect of hydrothermal reaction time and calcination temperature on the textural and morphological characteristics of the catalyst was investigated by TEM, SEM, XRD, XPS, ICP, UV–Vis, and N 2 adsorption–desorption techniques. The results proved that gold core and CeO 2 shell formed simultaneously at the beginning of the reaction. By extending the hydrothermal reaction time, both the grain size of Au core and CeO 2 shell increased. The crystallization degree of CeO 2 and the interaction between Au and CeO 2 were also enhanced. The 90 % CO conversion temperature (T 90 % ) of Au@CeO 2 declined from 187 to 142 °C with the hydrothermal reaction time extended from 6 to 20 h. After 70-h reaction, the catalytic activity was still maintained without any loss. The effect of the calcination temperature on the catalytic performance was also investigated and it turned out that high calcination temperature has a positive influence on the catalytic activity. The likely active sites are the interface between Au core and CeO 2 shell. Gold content, metal–support interaction (MSI), and oxygen vacancy are all related to the activity. The excellent performance of 20 h-600 °C-Au@CeO 2 in catalytic activity and stability results from the joint effects of these triple factors.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2020
·Vol. 20
·期 9
·5539-5545
·
IF 1.134
Yin Hao Yong,Zheng Yi Fan,Wang Ling
A convenient and simple phenol electrochemical sensor was constructed based on the Au/CeO2/ g-C3N4 nanocomposites, which were obtained by loading the gold–cerium oxide (Au/CeO2) nanoparticle on graphite-like carbon nitride (g-C3N4)
through precipitation–reduction methods. The microstructure and morphology of Au/CeO2/g-C3N4 nanocomposite were verified using different techniques such as XRD, TEM, and HRTEM. Voltammetry and amperometry methods were used to study the electrochemical
performance of the constructed phenol electrochemical sensors. The results demonstrated evidently that the combination of Au/CeO2 and g-C3N4 may improve sensing performances of phenol determination. The detection linear range of the sensor was 10–90 μM
under the optimum parameters. The Au/CeO2/g-C3N4 based electrochemical sensor also has low detection limits (2.33 μM) and high sensitivities (0.1080 mA/μM) for phenol detection. In addition, the sensor also had considerably favorable anti-interference
performance. As a consequence, the sensor demonstrated that the electrochemical system provided a promising effective strategy for detection of phenol.
研究领域:
分析化学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
Batteries-Basel
·
2024
·Vol. 10
·期 7
·235
·
IF 4.6
Tian Zhou,Jie Sun,Jigang Li,Shouping Wei,Fan Zhang,Jing Chen
In this study, a flower-like Au/CeO2supported catalyst composite anode was prepared to explore its impact on thermal runaway triggered by overcharging and flame. Through structural and performance characterization, it was found that the catalyst has a high specific surface area and good CO catalytic oxidation capability, with a CO removal rate higher than 99.97% at room temperature. Through electrical performance testing, it was discovered that, compared to batteries without the catalyst, batteries using the composite anode did not exhibit significant capacity degradation. In overcharge testing, the catalyst prolonged the voltage rise time and peak voltage occurrence time of the battery. In thermal runaway testing, the addition of the catalyst delayed the detection time of CO and significantly reduced the concentration of thermal runaway products, especially the peak concentration and integrated concentration of CO, demonstrating its effectiveness in reducing thermal runaway products. Therefore, this study provides a new approach for improving the safety of lithium-ion batteries. The catalyst exhibits good performance in reducing toxic gases generated after thermal runaway and delaying the occurrence of thermal runaway, providing strong support for the safe application of lithium-ion batteries.
研究领域:
材料科学
·
电化学
·
电池安全
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Zhiqing Cui,Weikang Wang,Cuijiao Zhao,Chun Chen,Miaomiao Han,Guozhong Wang,Yunxia Zhang,Haimin Zhang,Huijun Zhao
We present the self-assembly synthesis of core–shell structure Au/CeO2 composites with different Au loadings through a spontaneous chemical redox approach at an ambient temperature utilizing HAuCl4 and Ce(NO3)3 as reaction substrates in an alkaline environment. The results demonstrate that the as-synthesized Au/CeO2 composites exhibit spherical shape morphologies with porous structures, composed of Au nanoparticle (∼10 nm) cores and CeO2 nanoparticle shells with abundant oxygen vacancies. The introduction of Au nanoparticles in CeO2 not only effectively improves the visible light utilization efficiency but also provides rich surface catalytic active sites for highly efficient visible light photocatalysis. As visible light photocatalysts (λ > 400 nm), the as-synthesized Au/CeO2 composites with the Au loading amount ≥4.0 wt % exhibit high conversion and selectivity (∼100%) of benzyl alcohol to benzaldehyde under the given experimental conditions. Moreover, Au/CeO2 also shows a general applicability as a visible light photocatalyst for the selective oxidation of other alcohols to corresponding aldehydes or ketones. The photocatalytic mechanism studies indicate that the photoelectrons/holes produced from the photoexcited Au and the formed superoxide radicals in the oxygen vacancies of CeO2 synergistically contribute to the high performance of the selective photocatalytic oxidation of alcohols to aldehydes or ketones.
研究领域:
材料科学
·
光化学
·
催化科学
✓ 已验证
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2022
·Vol. 189
·期 12
·1-9
·
IF 6.408
Yuan Xiang,Zhang Huiling,Cao Huijuan,Mao Guojiang,Wei Lin
A visible and sensitive assay for the quantitative detection of β-glucosidase (β-glu) activity based on Au@CeO 2 core-shell nanoparticles (Au@CeO 2 NPs) is described. As a hydrolytic enzyme, β-glu can promote the hydrolysis of β-arbutin to hydroquinone (HQ), which can trigger the decomposition of the CeO 2 shell. With the single-particle enumeration (SPE) strategy coupled with dark field optical microscopy (DFM), an obvious color alteration of single Au@CeO 2 NPs during the etching process can be observed in real-time. By statistically calculating the number of the etched nanoparticles, the β-glu activity level can be quantified accurately. This assay displays a broad linear range from 0.5 to 50 mU⋅mL −1 and low detection limit of 0.12 mU⋅mL −1 . In addition, this method was successfully used to determine β-glu in real samples and acquires satisfactory recoveries in the range of 97.1-102.0%. This study provides a visualization analysis method for β-glu, which may be helpful for monitoring other targets in the future. Graphical Abstract
研究领域:
生物化学
·
纳米技术
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Tiancheng Li,Mengmeng Shu,Cheng Zhu,Yixin Li,Qicheng Liu,Zhiyu Zhu,Yangyang Jiang,Peng Mei,Yu Jin,Bing Fang,Lunguo Xia
In osteoarthritic chondrocytes, dysregulation of mitochondrial dynamics due to excessive intracellular reactive oxygen species (ROS) under inflammatory conditions is a significant contributory factor to poor treatment outcomes, because it leads to a reduced cell response to chondrogenic drugs during this state. The aim of this study was to develop a multifunctional Au@CeO 2 yolk-shell nanozyme (YSN) as a novel therapeutic nanomaterial and drug delivery system. Under photothermal conditions, Au@CeO 2 nanozymes neutralized excessive ROS, enhanced antioxidant capacity, and maintained mitochondrial homeostasis of osteoarthritic chondrocytes, thereby restoring cellular responsiveness to external stimuli. Furthermore, bioactive peptide CK2.1 loaded in YSNs (Au@CeO 2 -CK2.1) achieved ordered release under photothermal conditions, effectively promoting chondrocyte anabolic activity. In a mice osteoarthritis (OA) model, local Au@CeO 2 -CK2.1 photothermal therapy effectively enhanced cartilage repair and regeneration in vivo . Mechanically, our research uncovers that decreased chondrogenic drug response is associated with activation of extracellular regulated kinase-1 and -2 (ERK1/2) pathway, and Au@CeO 2 -CK2.1 YSNs regulates mitochondrial dynamics through inhibiting ERK1/2 and dynamin-1-like protein (DRP1) phosphorylation. The results of this study demonstrated an effective therapeutic strategy that rescued chondrogenic drug response in osteoarthritic chondrocytes, achieving anti-inflammation and cartilage regeneration.
研究领域:
纳米技术
·
生物材料
·
药物递送系统
·
再生医学
·
骨科
·
细胞生物学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Hao Tang,Zi Ang Chen,Muchen Wu,Shunbo Li,Ziran Ye,Mingjia Zhi
Tuning the size of Au nanoparticles is always an interesting task when constructing Au/semiconductor heterojunctions for surface plasmon resonance-enhanced photocatalysis. In particular, the size of Au nanoparticles in the newly emerging “plasmonic aerogel” photocatalyst concept could approach the size of the semiconductor phase. This work provides an alternative route to realize the size tuning of Au nanoparticles in Au-CeO 2 composite aerogels to some extent, within the framework of the well-established epoxide addition sol–gel method. The size tuning is achieved by exploiting the multi-functionalities of a mixed organic acid additive containing a thiol group in the gelation step. The obtained aerogel photocatalysts are composed of a porous backbone of interconnected CeO 2 nanoparticles and Au nanoparticles, and the size of Au nanoparticles ranges from ∼30 nm to sub-10 nm, while the size of CeO 2 remains at ∼15–10 nm. The surface plasmon resonance peak position and intensity contributed by the Au nanoparticles then vary accordingly. Photocatalytic CO 2 reduction at the gas–solid interface is chosen as a model reaction to study the effect of Au nanoparticle size on the photocatalytic activity of composite aerogel photocatalysts. The addition of Au nanoparticles undoubtedly enhances the overall activity of the CeO 2 aerogel photocatalyst, while the degree of enhancement (in terms of total charge consumption) and product selectivity (CH 4 or CO) are different and correlated with the size of the Au nanoparticles. The best performance can be achieved in a composite in which the Au sizes are the smallest.
研究领域:
材料科学
·
化学工程
·
环境科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）