Chemistry-An Asian Journal
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2020
·Vol. 16
·期 2
·165-173
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IF 4.056
Ying Duan,Yangyang Ma,Yanfu Xie,Dongmi Li,Dongsheng Deng,Chi Zhang,Yanliang Yang
The reasonable control of the dispersion of noble metals is an important topic for heterogeneous catalysts. In this manuscript, PdCu/C, AuCu/C and PdAuCu/C were prepared by the galvanic reduction method to ensure that Pd and Au follow the distribution of Cu nanoparticles. The catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy-dispersive spectrometer elemental mappings and lines scans. Both the Pd and Au had very high dispersion no matter whether they were introduced individually or simultaneously. The Pd and Au were distributed mainly on the Cu nanoparticles as evidenced by the energy-dispersive spectrometer elemental mappings and lines scans. The reduction of 4-nitrophenol was used as a model reaction for the prepared catalysts. PdCu/C and AuCu/C showed high activity for this reaction compared to the literature, and the activity could be further increased by the introduction of Pd and Au in an appropriate ratio at the same time. The normalized reaction rate reached 2.005 s −1 mM −1 for the PdAuCu/C-2.0, in which the mole ratio of Pd to Au was 2.0.
研究领域:
材料科学
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催化化学
✓ 已验证
DOI
高影响因子
Molecular Catalysis
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2024
·
IF 3.9
Zhenzhen Wang,Encheng Liu,Zhonghua Sun,Zhihui Zhang,Mingyang He,Qun Chen,Junfeng Qian
Formic acid (FA) is of great significance given its extensive applications in various industrial fields. At present, methanol carbonylation is the main industrial production process of FA. However, this process uses two kinds of raw materials from fossil fuels and emits a large amount of CO 2 . Alternatively, converting CO 2 into FA can not only achieve the production of value-added chemicals but also effectively address environmental issues caused by CO 2 emission. To improve the low reactivity of CO 2 , homogeneous and heterogeneous catalytic systems have been widely evaluated, among which heterogeneous catalytic systems are attracting ever-increasing attention owing to their great industrialization prospects. However, some of these heterogeneous catalysts suffer from low catalytic performance. Herein, PdAu alloy nanoparticles anchored on amine-functionalized hierarchical porous carbon (PdAu/HPC-AP) were constructed to drive efficient converting of CO 2 into FA. Characterization and testing results demonstrated that the introduced Au atoms caused lattice distortion and charge redistribution on the surface of the bimetallic catalyst, facilitating the adsorption and activation of reaction molecules. Furthermore, the modification of HPC with an appropriate amount of amine ligands was found important to the chemical adsorption of CO 2 and the dispersion of PdAu NPs. The Pd 60 Au 40 /HPC-AP catalyst with the optimum synergy of alloy and ligand demonstrated excellent activity for the target reaction with a TOF value of 486 h –1 at 100 °C. Moreover, it can even catalyze the reaction at room temperature with a TOF value of 13 h –1 .
研究领域:
催化化学
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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
International Journal of Electrochemical Science
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2024
·
IF 1.3
Yuning Qu,Ying Sun,Ming Song,Hao Wang,Ningru Xiao
An efficacious strategy to enhance the activity and stability of electrocatalysts for alcohol oxidation reactions is the formation of alloys of palladium with oxygenophilic metals. In this study, Palladium nano chains with an average diameter of approximately 4.4 nm were synthesized via a one-step hydrothermal approach, employing creatine as the structural guide. The one-dimensional structure yielded a huge electrochemically active area (84.5 m 2 g −1 ) and good electrical conductivity. the mass activity of Pd 87 Au 13 NCs for alkaline ethanol oxidation reaction was 4050 mA mg Pd+Au −1 , which is 7.32 times higher thancommercial Pd/C, and also maintains a high residual current density after 20000 s stability test. In addition, the excellent performance of the material was demonstrated during the oxidation of ethylene glycol and glycerol. The improved catalytic performance is owed to the interconnected chain shape providing fast electron transport channels, and the Au doping not only optimizes the electronic structure of Pd but also has a bifunctional effect, which effectively removes the carbon-containing intermediates generated by Pd during alcohol oxidation, thus improving its resistance to poisoning and stability.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2019
·
IF 0
Zhao Jiang,Shuyi Guo,Tao Fang
The design and development of catalysts for dodecahydro-N-ethylcarbazole (12H-NECZ) dehydrogenation restrict the achievement of the cyclic hydrogenation/dehydrogenation process. In this work, the M/SiO2 (M = Pt, Pd, Ru, Rh, Au) and bimetallic PdAu/SiO2 catalysts are prepared, and their catalytic performances are measured. By XRD, XPS, HRTEM, and CO pulse chemisorption, we find that the alloy structure is not generated and the average particle size increases with the improvement of the Au amount in the bimetallic catalysts. Besides, the catalytic performance can be enhanced dramatically with introducing a small amount Au. Pd3Au1/SiO2 exhibits the best catalytic performance with the complete conversion, 94.9 selectivity to NECZ, and 5.7 wt % hydrogen release amount. The TOF values are up to 240.7 min–1, 2.26 times higher than that of Pd/SiO2. The qualitative and quantitative analyses indicate that 4H-NECZ dehydrogenation is the rate-limiting step. It can be proposed that controlling the particle size and dispersion of the PdAu/SiO2 bimetallic catalysts will bring a significant enhancement of catalytic performance.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
ChemElectroChem
·
2018
·Vol. 5
·期 5
·778-784
·
IF 4.446
Yan Wei,Zhenlu Zhao,Ping Yang
Graphical Tip of the iceberg : Pd-tipped Au nanorods (NRs) are prepared in the presence of CTAB and 5-BrSA for the electrocatalytic hydrogen evolution reaction in the visible and near-infrared region. The tipped NRs exhibit a lower onset overpotential (40 mV) and higher exchange current density (1.585 mA/cm 2 ) than fully covered ones, which is ascribed to synergetic photothermal and photoelectric effects. Plasmonic bimetallic structures have been wildly used in photocatalysis, owing to their tunable optical properties and desirable catalytic activities. However, it is still a challenge to realize the enhanced electrocatalytic hydrogen evolution reaction (HER) using these structures with electric, photo-, and thermal effects. Herein, we report that Pd-tipped Au nanorods (NRs) were prepared for electrochemical water splitting in the visible and near-infrared region. The NRs exhibited a lower onset overpotential (40 mV) and high exchange current density (1.585 mA/cm 2 ), which was largely ascribed to the increased carrier density in Pd induced by photo-excited Au NRs, and further enhancement of Pd catalytic activity resulted from the photothermal effect of Au NRs. As the hot electron transport channel was hindered by excess Pd nanoparticles, it was found that the HER performance of tipped NRs was much higher than that of fully covered ones. This study extends enhanced electrocatalytic HER activity with plasmonic bimetallic structures by taking full advantage of the synergy between photoelectric and photothermal effects.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
·
IF 9.136
Yanju Chen,Chao Feng,Wenhong Wang,Zhi Liu,Junxi Li,Chenguang Liu,Yuan Pan,Yunqi Liu
Regulating the electronic structure of Pd catalyst for promoting electrocatalytic hydrodechlorination is promising but still challenging. Herein, we propose an electronic structure engineering for accelerating the hydrodechlorination process by desigining bimetallic Pd-Au alloy nanoparticles (ANs) with electron-rich Pd as high-efficiency electrocatalysts. The Pd 7 Au 3 ANs exhibits the highest electrocatalytic hydrodechlorination activity, the 4-chlorophenol hydrodechlorination efficiency reaches 98.35 % within 4 h, and the mass activity is 0.47 h −1 mg Pd −1 , which is 7.83 times as high as that of pure Pd nanoparticles. The experimental characterization and theoretical calculation reveal that Pd atoms “obtain” electrons and gold atoms “lose” electrons in Pd-Au ANs, resulting in the formation of electron-rich Pd, which promotes the desorption of the dechlorination product phenol and accelerates the renewal of active sites. This work provides an electronic structure engineering strategy of Pd-based electrocatalysts for electrocatalytic hydrodechlorination, which opens a new opportunity for rational design and construction of high-performance hydrodechlorination catalysts.
研究领域:
材料科学
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环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2022
·
IF 13.7
Shuchao Jiang,Junxia Yang,Shengliang Zhai,Ling Zhang,Rui Tu,Tie Yu,Dong Zhai,Lei Sun,Weiqiao Deng,Guoqing Ren
Formic acid (FA)/formate as a promising liquid organic hydrogen carrier exhibits great potential for future energy supplies. However, FA/formate-based hydrogen storage and release, which can be operated under ambient conditions, is challenging but attractive. Here, we report an ambient hydrogen storage and release process that uses the acidity and alkalinity of the reaction solution to control hydrogen production or consumption via an l-arginine-functionalized active carbon-supported PdAu alloy catalyst (PdAu/AC-LA). By regulating the LA loading and Pd/Au ratio, we obtain the optimal catalytic activity with turnover frequency (TOF) of 1760 h–1 for FA dehydrogenation under acidic conditions and 138 h–1 for CO2 hydrogenation under alkaline conditions. Comprehensive characterizations, including X-ray photoelectron spectroscopy (XPS), CO2 temperature-programmed desorption (CO2-TPD), and HCOO– adsorption experiments, reveal that the synergistic effect between PdAu alloy and strongly basic l-arginine enhances catalytic activity by regulating the adsorption of reactants. Our work, as a successful example of FA/formate-based hydrogen storage and release under ambient conditions, may aid putting the safe and energy-saving use of hydrogen into practice.
研究领域:
化学工程
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催化科学
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能源技术
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
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2019
·
IF 8.456
Yicheng Zhong,Yuelin Mao,Shunli Shi,Mingming Wan,Chong Ma,Shuhua Wang,Chao Chen,Dan Zhao,Ning Zhang
MNPs@MOF catalysts obtained by encapsulating metal nanoparticles (NPs) into metal–organic frameworks (MOFs) show fascinating performance in heterogeneous catalysis. The improvement of catalytic activity and reusability of MNPs@MOF catalysts has been a great challenge for a long time. Herein, we demonstrate well-designed Pd/MOFs, featuring hollow double-shell structure and magnetic property, exhibiting high reusability, efficient catalytic activity, and size selectivity for hydrogenation reaction. The as-synthesized Pd/MOF, denoted as Void nFe3O4@Pd/ZIF-8@ZIF-8, possesses diverse functional structural features. The hollow cavity can improve mass transfer; superparamagnetic Fe3O4 NPs embedded in the inner MOF shell can enhance the separation and recyclability; Pd NPs are highly dispersed in the matrix of the inner MOF shell, and the outer MOF shell acts as a protector to prevent the leaching of Pd NPs and a sieve to achieve size selectivity. As a proof of concept, the Void nFe3O4@Pd/ZIF-8@ZIF-8 catalyst exhibited excellent performance for the hydrogenation of styrene at room temperature. The activity only reduced 10% after 20 cycles for the higher conversions (>90%), and the lower conversion only decreased 3.6% (from 32.5 to 28.9% conversion) after twenty consecutive cycles, indicating the good and intrinsic reusability of the catalyst. The proposed structure in this work provides a strategy to effectively improve the reusability of MNPs@MOF catalysts, which would increase their practical applications.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED ELECTROCHEMISTRY
·
2016
·Vol. 46
·期 11
·1147-1155
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IF 2.223
Jin Biyao,Zhang Yanyu,Zhao Lianhua
Abstract PdAu 3:1/C-1 and PdAu 3:1/C-2 nanoparticles were prepared in methylene chloride and water, respectively. The syntheses featured the use of tetrabutylammonium hydroxide as a phase-transfer agent and stabilizer. Electrochemical characterization showed that compared with PdAu 3:1/C-2, PdAu 3:1/C-1 had superior ethanol oxidation reaction (EOR) activity in alkaline media. The results of X-ray powder diffraction indicated that PdAu 3:1/C-1 was an alloy, whereas PdAu 3:1/C-2 was a heterogeneous mixture of the two metals. Moreover, transmission electron microscope analyses revealed that the PdAu 3:1/C-1 nanoparticles dispersed homogeneously on the carbon carrier without evident aggregation. Further, the X-ray photoelectron spectroscopy results demonstrated that the hydroxyl content was higher on the surface of PdAu 3:1/C-1 than that of PdAu 3:1/C-2. The increase of adsorptive hydroxyl on the surface of PdAu 3:1/C-1 could facilitate the adsorption and oxidation of CO on the catalyst surface, thus improving EOR activity and catalyst stability. Graphical Abstract
研究领域:
化学
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材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2022
·
IF 24.319
Hongjing Wang,Wenxin Wang,Hongjie Yu,Qiqi Mao,You Xu,Xiaonian Li,Ziqiang Wang,Liang Wang
Engineering the interface between two-dimensional materials and polymers is of great importance to improve their catalytic performance for oxygen reduction reaction (ORR). Hence, polyaniline (PANI)-functionalized porous Pd metallene (Pd@PANI metallene) is prepared via a two-step strategy. Due to the ultrathin porous nanosheets and interfacial structure, the Pd@PANI metallene possesses sufficient active sites and optimized electronic structure, which exhibits superior oxygen reduction performance in alkaline electrolyte. The mass and specific activities for Pd@PANI metallene are measured to 1.79 A mg Pd −1 and 2.96 mA cm −2 , which are 11.9 and 9.30 times those of Pt/C (0.15 A mg Pd −1 and 0.32 mA cm −2 ), respectively. Additionally, the ORR performance and morphology of Pd@PANI metallene can be maintained after long-term stability testing, making it an excellent ORR catalyst. This work provides an effective interface engineering strategy to construct efficient two-dimensional ORR electrocatalysts to improve the performance.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Nano
·
2021
·
IF 15.881
Shaoda Huang,Shuanglong Lu,Shun Gong,Qiuju Zhang,Fang Duan,Han Zhu,Hongwei Gu,Weifu Dong,Mingliang Du
Engineering the morphology and electronic properties simultaneously of emerging metallene materials is an effective strategy for enhancing their performance as oxygen reduction reaction (ORR) electrocatalysts. Herein, a highly efficient and stable ORR electrocatalyst, Fe-doped ultrathin porous Pd metallene (Fe–Pd UPM) composed of a few layers of 2D atomic metallene layers, was synthesized using a simple one pot wet-chemical method and characterized. Fe–Pd UPM was measured to have enhanced ORR activity compared to undoped Pd metallene. Fe–Pd UPM exhibits a mass activity of 0.736 A mgPd–1 with a loss of mass activity of only 5.1% after 10 000 cycles at 0.9 V versus the reversible hydrogen electrode (vs RHE) in 0.1 M KOH solution. Density functional theory (DFT) calculations reveal that the stable Fe dopant in the inner atomic layers of Fe–Pd UPM delivers a much smaller overpotential during O* hydrogenation into OH*. The morphology, porous structure, and Fe doping were verified to have enhanced ORR activity. We believe that the rational design of metallene materials with porous structures and interlayer doping is promising for the development of efficient and stable electrocatalysts.
研究领域:
材料科学
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电化学
·
理论计算
✓ 已验证
DOI
PubMed
高影响因子
Nanoscale
·
2020
·Vol. 12
·期 21
·11659-11671
·
IF 6.895
Bowei Pan,Fuyi Chen,Bo Kou,Junpeng Wang,Quan Tang,Longfei Guo,Qiao Wang,Zhen Li,Weiqi Bian,Jiali Wang
High-performance Pd-based nanocatalysts for alkaline methanol and formate fuel cells have stimulated widespread attention. Hence, a series of ternary Pd–Au–Ag nanoalloys have been synthesized on carbon nanotubes, which demonstrate promising activity and unexpectedly high stability for the formate oxidation reaction (FOR) in alkaline medium. The ternary Pd3Au3Ag1 nanoalloy catalyst showed an initial mass activity of 4.51 A mgPd−1 and a retained mass activity of 1.32 A mgPd−1 after chronoamperometric measurement for 3600 s, which are superior to the best values for all FOR catalysts reported so far. The Pd3Au3Ag1 catalyst also showed a good specific activity of 4.32 mA cm−2 for the methanol oxidation reaction. Furthermore, surface reconstruction of the Pd3Au3Ag1 nanoalloy was observed during FOR, where the activity of Pd3Au3Ag1 catalysts increased up to 33% and the cycling durability retained 55% after cyclic voltammetry with the upper potential of 1.7 V. The FOR enhancement is attributed to the formation of mixed oxidation-state Ag sites and the increase in the Pd surface coverage, and provides a new prospect for the design of ternary nanoalloy electrocatalysts for various fuel oxidation reactions.
研究领域:
材料科学
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电化学
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能源科学
✓ 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）