ELECTROCHIMICA ACTA
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2020
·
IF 6.215
Hui Jiang,Lin Liu,Kai Zhao,Zhen Liu,Xinsheng Zhang,Shuozhen Hu
Nitrogen doping was widely used to increase the electronic density of carbon materials and to enhance the adsorption of the supported metal catalysts . However, the exact interaction between various doped nitrogen species and palladium (Pd) have rarely been reported for formic acid electrooxidation (FAO). In this study, the effect of the doped pyridinic-N and pyrrolic-N on the electronic structure and the electrochemical activity of Pd toward FAO are investigated. The oxidation state of Pd is reduced and more metallic Pd is formed when Pd nanoparticles supported on pyridinic-N and pyrrolic-N doped carbon materials . Density functional theory (DFT) calculations simulate that the adsorption energy of HCOO* and *COOH on Pd/pyrrolic-N are lower than those on Pd/pyridinic-N. Both DFT and electrochemical measurements suggest that the FAO activity of Pd is more correlated with the pyrrolic-N than pyridinic-N. The catalyst contains more pyrrolic-N species exhibits higher electrochemical activity and faster kinetics for FAO reaction. Moreover, Pd 2+ -N complexes are formed in all the nitrogen doped catalysts and display good activity for FAO. In this study, Pd supported on urea treated carbon (Pd/UR) owns the highest content of pyrrolic-N and exhibits the best activity for FAO.
研究领域:
材料科学
·
电化学
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高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2019
·
IF 2.781
Xiaofang Wan,Xinying Wang,Guangxue Chen,Congbao Guo,Bowen Zhang
Covalent organic frameworks (COFs) have attracted much attention due to their high porosity and highly ordered crystalline structure. However, the insoluble and unprocessable features of bulk COF powder limit their applications. To overcome these limitations, COF-TpPa film was prepared based on amine-group functionalized nanofibrillated cellulose (NFC) by Schiff base reaction for the first time. The obtained COF-TpPa/NFC membrane had high specific surface area (BET, 357 m 2 /g) and uniform pore size of 2–20 nm with the thickness of 250 nm. Via a simple post-treatment, a Pd-containing Pd@COF/NFC composite membrane , was accordingly synthesized, which showed excellent catalytic activity in catalyzing dechlorination of o -dichlorobenzene ( o -DCB) with high activity (the apparent reaction rate was 0.0235 min −1 ).We expect that our approach will further boost research on designing and employing functional COF film for catalysis.
研究领域:
材料科学
·
环境科学
·
催化化学
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高影响因子
NEW JOURNAL OF CHEMISTRY
·
2018
·Vol. 42
·期 20
·16694-16702
·
IF 3.201
Yongshen Ren,Yanxin Wang,Xun Li,Zehui Zhang,Quan Chi
In this study, we have developed a sustainable method for the hydrogenation of quinolines to 1,2,3,4-tetrahydroquinolines under mild conditions over a nitrogen-doped carbon-supported Pd catalyst with abundant porous structures (abbreviated as Pd/CN). The mesoporous structure of the nitrogen-doped carbon support was prepared by the pyrolysis of glucose and melamine using eutectic salts of KCl and ZnCl2 as the porogen. Due to the high nitrogen content in the support, Pd nanoparticles were homogeneously dispersed on the surface of nitrogen-doped carbon materials with an ultra-small size of 1.9 nm in a narrow size distribution. The as-prepared Pd/CN catalyst showed high catalytic activity towards the hydrogenation of quinolines at 50 °C and 20 bar H2, affording the corresponding 1,2,3,4-tetrahydroquinolines with yields in the range of 86.6–97.8%. More importantly, the Pd/CN catalyst was highly stable without the loss of its catalytic activity during the recycling experiments. The use of renewable resources to prepare the catalyst makes this method promising for the sustainable 1,2,3,4-tetrahydroquinolines from the hydrogenation of quinolines.
研究领域:
催化化学
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绿色化学
·
材料科学
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高影响因子
Journal of Biobased Materials and Bioenergy
·
2017
·Vol. 11
·期 5
·477-482
·
IF 0.975
Xu Jianxiong,Xie Shaowen,Li Changyun,Xu Lijian
Hierarchically nanoporous silicon hydrogen compound particles were synthesized by dissolving template method, and the hierarchically nanoporous Pd–HSiO1.5 were further prepared by in-situ synthesis method. The microstructure and morphology of the nanoparticles
were characterized by the transmission electron microscopy (TEM). In addition, the hierarchically nanoporous Pd–HSiO1.5/Ni–Co composite electrode was fabricated by the method of nanocomposite electrodeposition, in which hierarchically nanoporous Pd–HSiO1.5
particles were used as composite nanoparticles on the Ni–Co electroplating bath. The surface morphology was characterized by the scanning electron microscopy (SEM). Finally, the sensor was used to detect the tetracycline antibiotics with different classes. Results showed that the hierarchically
nanoporous silicon hydrogen compound particles were with hollow spherical structure. The size of the hollow spheres was about 70 nm, and the thickness of the spherical shell was about 10 nm. The Pd nanoparticles were successfully loaded on the inside and surface of the hierarchically nanoporous
silicon hydrogen compound. The size of the inside Pd nanoparticles was about 3 nm, and the size of surface Pd nanoparticles was 10–30 nm. In addition, the SEM image showed that the hierarchically nanoporous Pd–HSiO1.5 particles were uniformly inlaid on the surface of
the hierarchically nanoporous Pd–HSiO1.5/Ni–Co composite electrode. The composite electrode had high electrocatalytic activity and showed high electrochemical sensitivity in the detection of the oxytetracycline and deoxytetracycline in alkaline medium. The obtained detection
limits were 1.0 × 10–8 M and 5.0 × 10–8 M for oxytetracycline and deoxytetracycline, respectively.
研究领域:
分析化学
·
生物医学工程
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高影响因子
Catalysts
·
2023
·Vol. 13
·期 4
·651
·
IF 3.9
Jiaqi Du,Yidan Peng,Xu Guo,Guoliang Zhang,Fengbao Zhang,Xiaobin Fan,Wenchao Peng,Yang Li
Researchers studying heterogeneous catalysis are intrigued by single-atom catalysts (SACs) due to their ultrahigh atomic utilization. However, only a few reports on SAC-catalyzed classical organic transformations are available. In this work, atomically dispersed Pd sites are confined to a ZrO2hybridized N-doped carbon skeleton with a smart design. UiO-66-NH2is used to anchor Pd atoms by the coordination of the donor atoms including lone pairs of electrons and metal atoms. Subsequently, the in situ introduction of ZrO2doping is achieved using pyrolysis, which helps improve the catalytic performance by modulating the electronic state. The Pd@ZrO2/N–C catalyst obtained from the unique design exhibits a high yield (99%) in eco-friendly media with an extremely low noble metal dosage (0.03 mol% Pd) for the Suzuki reaction. Moreover, Pd@ZrO2/N–C remains highly active after being reused several times and possesses versatility in a variety of substrates. This strategy offers a feasible alternative to designing SACs with atomically dispersed noble metals for heterogeneous reactions.Keywords:palladium;heterogeneous catalyst;Suzuki reaction;ZrO2doping;N-doped carbon
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ACS Applied Nano Materials
·
2023
·
IF 5.9
Lulu Kong,DeZhu Chen,Xiaolong Zhang,Lin Zhou,Yongming Deng,Shaohua Wei
The growth of oxides on the surface of noble metals and the introduction of alloys are effective methods to enhance the catalytic activity of noble metals. However, the fabrication of noble metal oxides always involves harsh experimental conditions and the oxidation degree could not be controlled. Herein, a simple, fast, and controlled Pd oxidation method by mixing Hg2+ and Pd nanosheets (PdNSs) under mild conditions to form PdxHgy(PdO)z (PHOs) was reported, which consists of the Pd–Hg alloy and PdO. The density functional theory (DFT) calculation and experiment results proved that the Hg atom incorporation promotes the nearby Pd–Pd bond breaking, initiating a cascade of PdO generation. More precisely, 1 Hg atom incorporation induced ∼8 Pd atom oxidation, ensuring that the oxidation degree of Pd could be easily controlled by adjusting the ratio of Hg2+ and PdNS. As a peroxidase-mimicking nanozyme, the PHO affinity for its substrate could be 21.7- and 123.6-fold greater than that of the PdNS and the natural peroxidase (HRP), respectively. For the colorimetric immunoassay of carcinoembryonic antigen (CEA) detection, PHO has an ultralow detection limit of 1.33 pg mL–1, which is ∼8.6 and ∼282 times lower than that of the PdNS and the natural HRP, respectively.
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AICHE JOURNAL
·
2023
·Vol. 69
·期 7
·e18085
·
IF 3.7
Wei Wang,Baian Pu,Chi Ma,Chengxiang Shi,Lun Pan,Xiangwen Zhang,Ji-Jun Zou
Cyclopropane derivates are appealing to synthesis of high-energy-density fuels because of the high strained energy of the three-numbered ring. The catalytic cyclopropanation of olefin with diazomethane is very effective to construct the carbocycle. The majority of the catalysts employed are nonrecyclable homogeneous compounds. Herein, we report cyclopropanation of polycyclic olefins catalyzed by heterogeneous Pd/C. The optimal cyclopropanation conditions were explored utilizing dicyclopentadiene as model substrate and a series of polycyclic olefins were cyclopropanated with high yield. Additionally, the catalyst has good recyclability and stability, as shown by characterizations as well as the fact that no inactivation happens after cyclopropanation. The synthesized cyclopropane derivates exhibit good fuel characteristics like high density (1.006–1.087 g/cm 3 ), high volumetric net heat of combustion (42.58–46.45 kJ/cm 3 ), good low-temperature and combustion performance. This work shows industrial potential for cyclopropanation of polycyclic olefins with diazomethane.
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ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Wenxia Fan,Ani Wang,Lei Wang,Xin Jiang,Zhenzhen Xue,Jinhua Li,Guoming Wang
Delicate design and bottom-up synthesis of hollow nanostructures for oxygen evolution electrocatalysts is a promising way to accelerate the reaction kinetics of overall water splitting. Herein, an efficient and versatile strategy for the controllable preparation of Pd–Cu alloy nanoparticles encapsulated in carbon nanopillar arrays (PD–Cu@HPCN) is developed. Core–shell structured MOF@imidazolium-based ionic polymers (ImIPs) have been prepared and adopted as a template, along with the decomposition of the inner Cu–MOFs when an anion exchange occurs between sodium tetrachloropalladate in solution and bromides in the external ImIP shell. Pd nanoparticles will be highly dispersed in the resulting Pd–Cu@HO-ImIP array, and subsequent topotactic transformation generates Pd–Cu@HNPC. No hazardous reagents or tedious steps are used to remove the inner Cu–MOF templates in contrast to the traditional top-down methods. Remarkably, the Pd–Cu@HPCN catalyst possesses outstanding oxygen evolution reaction (OER) activity, including small overpotential with 10 mA cm–2 at an overpotential of 188 mV, a large double layer capacitance (73.8 mF cm–2), and high stability (20 h). This simple, green, and efficient synthesis methodology represents a new way to design metal alloys for OER electrocatalysts or other electrocatalytic devices.
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PubMed
高影响因子
Catalysts
·
2023
·Vol. 13
·期 4
·643
·
IF 3.9
Minming Bao,Yuxi Liu,Jiguang Deng,Lin Jing,Zhiquan Hou,Zhiwei Wang,Lu Wei,Xiaohui Yu,Hongxing Dai
The development of efficient and stable catalysts is of great importance for the elimination of volatile organic pollutants (VOCs). In this work, AuPdxnanoparticles (NPs) were loaded on TiO2through the electrostatic adsorption approach to generate theyAuPdx/TiO2(i.e., 0.35AuPd0.46/TiO2, 0.34AuPd2.09/TiO2, and 0.37AuPd2.72/TiO2;xandyare Pd/Au molar ratio and AuPdxloading, respectively;x= 0.46–2.72; andy= 0.34–0.37 wt%) catalysts, and their catalytic activities for the oxidation of ethyl acetate were determined. The results showed that the 0.37AuPd2.72/TiO2sample exhibited the best activity (T50%= 217 °C andT90%= 239 °C at SV = 40,000 mL/(g h),Ea= 37 kJ/mol, specific reaction rate at 220 °C = 113.8 µmol/(gPds), and turnover frequency (TOFNoble metal) at 220 °C = 109.7 × 10−3s−1). The high catalytic performance of the 0.37AuPd2.72/TiO2sample was attributed to the good dispersion of AuPd2.72NPs, the strong redox ability, the large ethyl acetate adsorption capacity, and the strong interaction between AuPdxand TiO2. Acetaldehyde, ethanol, and acetic acid are the main intermediates in the oxidation of ethyl acetate, and the loading of AuPdxNPs effectively reduces the formation of the toxic by-product acetaldehyde. The oxidation of ethyl acetate over the 0.34AuPd2.09/TiO2sample might occur via the pathway of ethyl acetate → ethanol → acetic acid → acetate → CO2and H2O. We believe that the obtained results may provide a useful idea for the design of bimetallic catalysts under industrial conditions and for understanding the VOCs oxidation mechanisms.Keywords:supported Au–Pd nanocatalyst;ethyl acetate oxidation;strong electrostatic adsorption;sulfur dioxide resistance;reaction mechanism
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Advanced Science
·
2023
·
IF 15.1
Saijun Wang,Zaigang Zhou,Rui Hu,Mingyue Dong,Xiaobo Zhou,Siyan Ren,Yi Zhang,Chengxun Chen,Ruoyuan Huang,Man Zhu,Wanying Xie,Ling Han,Jianliang Shen,Congying Xie
At present, radiotherapy (RT) still acquires limited success in clinical due to the lessened DNA damage under hypoxia and acquired immune tolerance owing to the amplified programmed death ligand-1 (PD-L1) expression. Incredibly, intracellular PD-L1 expression depression is proven to better sensitize RT by inhibiting DNA damage repair. However, the disability of the clinically used antibodies in disrupting the extracellular PD-L1function still limits the effectiveness of radio-immunotherapy. Therefore, better PD-L1 regulation strategies are still urgently needed to better sensitize radio-immunotherapy. Hence, for this purpose, TPP-LND is synthesized by linking mitochondrial-targeted triphenylphosphine cations (TPP + ) to the antineoplastic agent lonidamine (LND), which significantly reduces the dose needed for LND to induce effective oxidative phosphorylation inhibition (2 vs 300 µ M ). Then, TPP-LND is wrapped with liposomes to form TPP-LND@Lip nanoparticles. By doing this, TPP-LND@Lip nanoparticles can sensitize RT by reversing the hypoxic microenvironment of tumors to generate more DNA damage and reducing the expression of PD-L1 via enhancing the adenosine 5′-monophosphate-activated protein kinase activation. As expected, these well-designed economical TPP-LND@Lip nanoparticles are more effective than conventional anti-PD-L1 antibodies to some extent.
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PubMed
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2023
·
IF 4.7
Qiqi Lu,Xiu-Zhi Wei,Haiyong Wang,Qi zhang,Xinghua Zhang,Lungang Chen,Jianguo Liu,Longlong Ma
The selective hydrogenation of nitrile represents an atom-economical and reliable method to synthesize primary amine, a privileged compound in chemistry, biology, and medicine. However, this approach often displays severe selectivity issues, and additives or reducing agents are generally required to solve this problem. In this work, we aim to synthesize primary amine on a green catalytic system and probe into the catalytic mechanism of Pd-Ni interaction using benzonitrile (BN) as a model compound. The nitrile hydrogenation reaction was catalyzed by bimetallic Pd-Ni oxide nanospecies confined in Silicalite‑1 (S-1) zeolite using H 2 as hydrogen donor without any additive which was environmentally friendly and economic. A 92% yield of benzylamine (BA) was achieved on the [email protected] catalyst with a turnover number (TON) of 1667, and such BA yield was still maintained in upscaling experiment. Detailed characterizations shed light on the mechanism of the extraordinary performance of Pd-Ni oxide nanospecies on base-free nitrile hydrogenation.
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高影响因子
ChemistrySelect
·
2023
·Vol. 8
·期 13
·e202202681
·
IF 2.1
Qing-Qing Pang,Xi-Zheng Fan
Graphical The ultra-fine Pd nanoparticles (NPs) are constructed by strong electrostatic adsorption strategy to ensure ample active sites, further enhance the light absorption intensity and optimize the separation efficiency of electron and hole, contributing to dramatically promote the performance of photocatalytic CO 2 reduction and stability in the gas-solid phase system. The photocatalytic CO 2 converted into the value-added products is regarded as a green strategy for the conversion and utilization of energy. Herein, we develop a commodious SEA (strong electrostatic adsorption) strategy to synthesize Pd-based photocatalysts with ultra-fine Pd NPs (Pd/TiO 2 −S−B). As verified by experiments and characterizations, the ultra-fine Pd NPs can inexorably heighten the reaction activity of catalyst, because it can provide several functions consist of improving the carrier separation efficiency, light absorption and CO 2 molecules adsorption. Meanwhile, the interaction of Pd and substrate can prevent the agglomeration of Pd NPs in reaction process. The designed Pd/TiO 2 −S−B contributes excellent performance in a gas-solid system. The yields of CO (105.1 μmol/g-cat) and CH 4 (254.3 μmol/g-cat) detected, are about 5.25 and 6.24-fold higher than those of pristine TiO 2 . Pd/TiO 2 −S−B also exhibits the forceful stability with acceptable decline of catalytic activity after three cycles. This opens the door for the preparation of high-performance and steady photocatalysts by reliable and effortless strategies toward CO 2 reduction.
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