Catalysts
·
2018
·Vol. 9
·期 1
·2
·
IF 3.465
Bingxu Chen,Bangfen Wang,Yuhai Sun,Xueqin Wang,Mingli Fu,Junliang Wu,Limin Chen,Yufei Tan,Daiqi Ye
The performance of plasma-modified Pt/CeO2for toluene catalytic oxidation was investigated. Pt/CeO2nanorods were prepared by wet impregnation and were modified by thermal (PC-T), plasma (PC-P), and combined (PC-TP and PC-PT) treatments. The modified catalysts were characterized by TEM (transmission electron microscope), BET (Brunauer-Emmett-Teller), H2-TPR, O2-TPD, XPS, UV-Raman, and OSC tests. The significant variation of the surface morphologies and surface oxygen defects could have contributed to the modification of the Pt/CeO2catalysts via the plasma treatment. It was found that plasma could promote the surface interaction between Pt and CeO2, resulting in the thermal stability of the catalyst. The Pt-Ce interaction was also conducive to an increase in the number of oxygen vacancies. Furthermore, PC-PT and PC-TP showed a significant difference in oxygen vacancy concentrations and catalytic activities, which illustrated that the treatment sequence (plasma and thermal treatment) affected the performance of Pt/CeO2. The PC-PT sample showed the highest catalytic activity with T100at 205 °C. This work thus demonstrates that plasma in combined treatment sequences could assist surface interactions of catalysts for enhanced toluene catalytic oxidation.Keywords:non-thermal plasma;Pt/CeO2;oxygen vacancies;treatment Sequence
研究领域:
催化化学
·
环境科学
✓ 已验证
DOI
高影响因子
ACS Catalysis
·
2025
·
IF 13.1
Zhitong Zhou,Weixiang Guan,Xiaoli Pan,Aiqin Wang,Tao Zhang
One-pot amination coupling of vicinal diols toward the synthesis of pyrazines provides an efficient and economically viable route to access N-heterocycles from biomass, yet the current methodology relies on a fragile homogeneous catalyst system, which limits the sustainability of the chemistry. In this work, we developed a highly efficient heterogeneous catalyst 0.8Pt/13CeO2/Al2O3 which afforded diverse substituted pyrazines from readily available vicinal diols and ammonia with a yield up to 94% under mild reaction conditions and could be reused at least 6 times without obvious activity decay. Compared to the Pt/Al2O3 catalyst, the 0.8Pt/13CeO2/Al2O3 catalyst exhibited a 30-fold faster conversion rate of diols and an increased pyrazine selectivity from 48% to 79%. Characterizations revealed that doped CeO2 improved the dispersion of Pt, increased the electron density on the Pt sites, optimized the acid/basic property of the catalyst, and enhanced the adsorption strength and dehydrogenation ability of diols. All these features contributed to the increased activity and selectivity.
研究领域:
化学工程
·
催化化学
·
生物质利用
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Fuyuan Qi,Weiping Yang,Lan-Lan Lou,Shuangxi Liu,Kai Yu
Oxygen vacancies play an important role in the oxidation of biomass-derived alcohols and aldehydes using ceria-based catalysts. In this study, a highly oxygen vacancy-defective Pt/H-CeO 2 catalyst was synthesized by a straightforward strategy that involved the control of the addition of ascorbic acid and nitric acid. The addition of ascorbic acid, which acted as a pore-forming agent, promoted the hydrolysis, crystallization, and subsequent growth of Ce precursor salt, resulting in the synthesis of H-CeO 2 with abundant oxygen vacancy defects and a porous thin sheet-like morphology. However, the addition of nitric acid significantly inhibited the generation of oxygen vacancy defects. The obtained H-CeO 2 exhibited significantly increased oxygen vacancy content, active oxygen species, and specific surface area compared with CeO 2 with lower oxygen vacancy defects (L-CeO 2 ). These remarkable features led to enhanced catalytic activity of Pt/H-CeO 2 for the oxidation of 5-hydroxymethylfurfural (HMF) compared with Pt/L-CeO 2 . This can be mainly attributed to the enhanced adsorption and activation of O 2 molecules by abundant oxygen vacancies, allowing more active oxygen species to participate in the dehydrogenation of HMF. This work provides an example of oxygen defect engineering for ceria-based catalysts to boost the catalytic selective oxidation performance.
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
ACS Catalysis
·
2018
·
IF 11.384
Yan Long,Shuyan Song,Jian Li,Lanlan Wu,Qishun Wang,Yu Liu,Rongchao Jin,Hongjie Zhang
Designing metal–organic framework (MOF)-encapsulated hybrid catalysts is considered as an effective way to realize catalytic selectivity because of advantages related to the unique channels of MOF. Here, a sodium polystyrenesulfonate (PSS)-induced, microwave-assisted route was developed to controllably construct Pt/CeO2@MOF core@shell hybrids. Using PSS as a modifying agent and followed by microwave assistance, MOFs could be continuously grown in an oriented manner on Pt/CeO2 nanospheres. The obtained Pt-CeO2@UIO-66-NH2 exhibited high conversion (99.3%) with high selectivity (>99%) for selective hydrogenation of furfural to furfuryl alcohol. It showed that the CeO2 would promote the catalytic activity, whereas the size confinement effect of the UIO-66-NH2 channels can enhance the catalytic selectivity. This work highlights a useful strategy toward the universal synthesis of highly active, stable, and selective catalysts for further utilization.
研究领域:
催化
·
材料科学
·
化学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2024
·
IF 3.9
Mingzhen Huang,Jinxin He,Kaiji Xu,Dongren Cai,Guowu Zhan
The supported Pt/CeO 2 catalysts are widely used for the catalytic oxidation of CO at ambient conditions. Herein, we reported a new strategy for modifying the interaction between Pt and CeO 2 support via pulsed steam treatment, which significantly optimized the catalytic performance of Pt/CeO 2 for CO oxidation. Specifically, the hollow CeO 2 nanospheres were prepared by using carbon spheres as sacrificial templates and then subjected to pulsed steam treatment at 150 °C for different times to obtain the CeO 2 -xH support (x means the time of pulsed steam treatment, min). It was found that the complete oxidation of CO can be achieved at 90 °C over the Pt/CeO 2 –50H sample, which was much lower than that (130 °C) on Pt/CeO 2 without pulsed steam treatment. The XPS and in-situ DRIFTS characterizations were conducted to reveal the high performance of the Pt/CeO 2 –50H catalyst for CO oxidation. It was found that the valence state of Pt significantly controlled by pulsed steam treatment was critical to the catalytic activity, whereby the presence of two types of active sites (Pt 0 -CO and Pt δ+ -CO) over Pt/CeO 2 –50H greatly promoted the combination of adsorbed CO and O 2 to generate CO 2 . Accordingly, this study provides a facile method to regulate the Pt valence state by pulsed steam treatment for CeO 2 support, which is critical to the CO oxidation activity.
研究领域:
催化化学
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ChemCatChem
·
2022
·Vol. 14
·期 16
·e202200509
·
IF 5.497
Jiefei Li,Zhenyu Li,Zexuan Zheng,Xueqiong Zhang,Hao Zhang,Hang Wei,Haibin Chu
Graphical Biomass conversion : Electro-oxidation of glycerol over the Pt/CNT catalyst suffers from the poor activity, low glyceric acid (GLYA) selectivity, and high cost of the noble metal. The incorporation of CeO 2 into Pt/CNT achieves much enhanced yield of GLYA with even half dosage of Pt. Electrocatalytic oxidation of glycerol is a highly efficient way for upgrading glycerol toward fine chemicals. Currently, electro-oxidation of glycerol into the high value-added C3 products remains a big challenge because of the poor catalytic activity, low selectivity, and high cost of the noble metal catalysts, especially in the alkaline medium. Here, we report that the Pt−CeO 2 /CNT (CNT=carbon nanotubes) catalyst remarkably promotes the conversion (86.5 % vs. 37.6 %) and recycling stability for glycerol electro-oxidation reaction, as compared with Pt/CNT. However, the improved catalytic activity of Pt−CeO 2 /CNT is accompanied by the further oxidation of C3 products including glyceric acid (GLYA). By tuning the product distribution by the ratio of CeO 2 and CNT, applied potential, and the Pt loading amount, the high selectivities of C3 products (95 %) and GLYA (59 %) are achieved together with the high glycerol conversion (86 %), leading to the impressive yields of C3 products (81 %) and GLYA (50 %). The unique contributions of CeO 2 includes not only the enhanced catalytic activity and recycling stability, but also the suppressed further oxidation of GLYA. Moreover, higher yield of GLYA is reached over Pt−CeO 2 /CNT even with half loading of Pt, as compared with Pt/CNT.
研究领域:
化学工程
·
催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2017
·
IF 6.065
Shunxing Li,Jiabai Cai,Xueqing Wu,Biwen Liu,Qiaoying Chen,Yuehai Li,Fengying Zheng
An solar-light-driven and bifunctional photocatalyst was designed for photo-reduction of Cr(VI) and selective photo-oxidation of benzyl alcohol into benzaldehyde in the presence of water under ambient conditions. Double-shelled and sandwiched TiO 2 @Pt@CeO 2 hollow spheres were prepared by using functionalized polystyrene spheres, sol-gel, hydrothermal reaction, and calcination. The Pt nanoparticles (NPs) were controllably loaded between the TiO 2 shell and CeO 2 shell. Under solar-light irradiation, the photo-reduction rate of Cr(VI) (μmol h −1 ) was in the order of TiO 2 @Pt@CeO 2 (1.901) > TiO 2 @CeO 2 (1.424) > TiO 2 (1.040) > CeO 2 (0.992). Among the above-mentioned photocatalysts, the conversion rate of benzyl alcohol for TiO 2 @Pt@CeO 2 was also the best. These results were attributed to the combination of TiO 2 and CeO 2 as photocatalyst and oxygen buffer, the double-shelled and sandwiched nanostructure, and the addition of Pt NPs as cocatalyst and electron trap site, which could store and shuttle photo-generated electrons, reduce the recombination of the electron-hole, and then enhance photo-generation of active radicals. This conclusion was verified by the electron paramagnetic resonance (EPR) spectroscopy. Considering the versatile combination of photocatalyst, oxygen buffer and cocatalyst, this work could provide new insights into the design of high-performance bifunctional photocatalysts for heavy metal removal and selective synthesis.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Huihui Shi,Peixin Yang,Lu Huang,Yali Wu,Duohuan Yu,Hangfei Wu,Yunhuai Zhang,Peng Xiao
The design and manufacture of high activity and thermal stability catalysts with minimal precious metal loading is essential for deep degradation of volatile organic compounds (VOCs). In this paper, a novel single-atom Pt-CeO 2 /Co 3 O 4 catalyst with ultra-low Pt loading capacity (0.06 wt%, denoted as 0.06Pt-SA) was fabricated via one-step co-precipitation method. The 0.06Pt-SA exhibited excellent toluene degradation activity of T 90 = 169 °C, matched with the nanoparticle Pt-supported CeO 2 /Co 3 O 4 catalyst with more than six times higher Pt loading (0.41 wt%, denoted as 0.41Pt-NP). Moreover, the ultra-long durability (toluene conversion remains 99% after 120 h stability test) and excellent toluene degradation ability in a wide space speed range of 0.06Pt-SA were superior to that of 0.41Pt-NP catalyst. The excellent performance was derived from the strong metal-support interaction (SMSI) between the single atomic Pt and the carrier, which induced more Pt 0 and Ce 3+ for oxygen activation and more Co 3+ for toluene removal. The in situ diffuse reflectance infrared spectroscopy (DRIFTS) experiments confirmed that the conversion of intermediates was accelerated in the reaction process, thereby promoting the toluene degradation. Our results should inspire the exploitation of noble single-atomic modification strategy for developing the low cost and high performance VOCs catalyst.
研究领域:
催化化学
·
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF RARE EARTHS
·
2022
·
IF 4.632
Luyao Zhang,Fuli Tian,Huan Li,Jiangman Meng,Qi Liu,Xiaoqian Guo,Yun Qiu,Jun Zhang,Changyan Li
A series of non-enzymatic graphene functionalized biosensors was developed via deposition precipitation method for lactic acid (LA) detection, which were characterized by transmission electron microscopy (TEM), Raman spectroscopy , X-ray photoelectron spectroscopy (XPS), gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry, and proton nuclear magnetic resonance ( 1 H NMR). The electrochemical performances of the non-enzymatic biosensors were measured by means of the electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) method. The comprehensive analysis of structures shows that Pt, CeO 2 , and GO components interact with each other. During the storing and releasing oxygen, the valence ratio of Ce 3+ /Ce 4+ and the number of oxygen vacancies in CeO 2 change accordingly, which can be conducive to increasing electronic transmission capacity and finally leads to the improvement of electrocatalytic performance. Among them, the Pt/CeO 2 /GO biosensor containing 0.47 at% platinum exhibits an excellent electrochemical detection performance with high sensitivity of 12.3 µA·L/ (mmol·cm 2 ) and a low limit of detection (LOD) of 5.12 μmol/L in a wide linear range from 10 to 900 μmol/L. In addition, the proposed biosensor possesses a promising anti-interference capability, as well as high stability and good reproducibility, which was assessed by testing the cyclic voltammogram in 0.1 mol/L lactic acid one year later. The underlying mechanism was proposed for electrochemical oxidation of LA to carbon dioxide and acetic acid with the synergistic effect among Pt, CeO 2 , and GO. Furthermore, the results of the standard addition method in real samples (human serum and urine samples) reveal that the lactic acid detection of the non-enzymatic Pt/CeO 2 /GO biosensor is accompanied by high reliability. Thus, it will be a valuable biosensor for in vitro detection of lactic acid level in clinical samples.
研究领域:
生物医学工程
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
Science China-Chemistry
·
2022
·Vol. 65
·期 10
·2038-2044
·
IF 10.138
Wang Yanan,Pei Chunlei,Zhao Zhi-Jian,Gong Jinlong
Rational design and performance promotion are eternal topics and ultimate goals in catalyst preparation. In contrast, trial—and—error is still the common method people take. Therefore, it is important to develop methods to intrinsically enhance the performance of catalysts. The most effective solutions are the one from a kinetic perspective based on clear knowledge of the reaction mechanism. This paper describes rate-determining step cognition and modulation to promote CO oxidation on highly dispersed Pt on CeO 2 . The different degrees of metal—support interactions due to variation of hydroxyl density of support could alter the structure of active species and the ability of oxygen activation apparently, further shift the rate-determining step from oxygen activation to oxygen reverse spillover kinetically. The transformation of rate-determining step could enhance the intrinsic activity significantly, and decrease the T 50 approximately 140 °C. The findings of this research exemplify the universal and effective method of performance elevation by rate-determining step modulation, which is promising for application in different systems.
研究领域:
催化
·
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Inorganic and Organometallic Polymers and Materials
·
2019
·Vol. 30
·期 5
·1589-1599
·
IF 1.637
Zhao Peng,Zhang Jinteng,Jiang Jingjing,Wang Hongtao,Xie Tengfeng,Lin Yanhong
A novel Pt/CeO 2 /ZnO ternary composite is synthesized via two simple procedures of hydrothermal and photoreduction. The crystal structure, morphology, and composition of as-prepared samples are characterized by XRD, SEM, HRTEM, XPS and UV–Vis DRS. Because both ZnO and CeO 2 are good photocatalytic semiconductors, photocatalytic activities of the samples are evaluated by the degradation of phenol aqueous solution (25 mg/L). Under the strong interaction among the Pt, CeO 2 and ZnO, the maximum photocatalytic activity is observed in the Pt/CeO 2 /ZnO ternary composites and 91% phenol can be degraded in 60 min under UV light irradiation. The probable photocatalytic mechanism is discussed by active species trapping experiments along with SPV, TPV, PL and PA measurements. The enhanced photocatalytic activity is attributed to the redox cycle of Ce 4+ ↔ Ce 3+ , the effective interface between ZnO and CeO 2 as well as the electron transfer action of Pt nanoparticles. The photocatalytic activity almost unchanged after four cycles and proves excellent reusable photocatalysts. This work shows the synergistic effect of rare earth elements and noble metals in the photocatalytic process, which facilitates their practical application in toxic pollution abatement.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2021
·
IF 4.126
Liwei Wang,Rongrong Han,Yanfu Ma,Melis S. Duyar,Wei Liu,Jian Liu
More than 25% of chemical transformations involve at least one hydrogenation step. Selective hydrogenation of unsaturated aldehydes is an essential process in the industrial production of pesticides and pharmaceutical synthesis. Since C═C hydrogenation with lower bond energy is thermodynamically favored over C═O hydrogenation, the selective hydrogenation of cinnamaldehyde (CAL) to cinnamyl alcohol (COL) is relatively challenging. Herein, we report a series of Pt-CeO2 nanoreactors with different spatial locations and microenvironments of Pt nanoparticles (NPs) on hollow CeO2 that are active for the selective hydrogenation of CAL to COL. We show the effects of active metal spatial location, microenvironment, metal–support interactions, and Fe doping on the activity and selectivity within Pt-CeO2 nanoreactors. Pt@Fe-CeO2 shows excellent catalytic performance with an 88.9% selectivity for COL at a CAL conversion of 97.2%. The variations of the electronic and crystal structure after Fe doping, simultaneously, and the linear adsorption of CAL on the CeO2 hollow structure contribute to the high performance of selective hydrogenation to COL. Our findings might shed light on the rational design of the nanoreactors for catalytic organic transformations with desired selectivity.
研究领域:
催化化学
·
材料科学
·
有机合成
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）