RSC Advances
·
2016
·Vol. 6
·期 27
·22908-22916
·
IF 3.289
Jianwen Tian,Xiaohui He,Jingyin Liu,Xiaodan Deng,Defu Chen
Palladium(II) and copper(II) chloride complexes bearing bulky 9,10-dihydro-9,10-ethanoanthracene-11,12-diimine ligands were synthesized and sufficiently characterized by elemental and spectroscopic analysis along with X-ray diffraction analysis. The X-ray diffraction demonstrated that palladium(II) complexes (C1–C2) and copper(II) complexes (C3–C4) were four-coordinated. All these complexes displayed catalytic activities up to 105 gpolymer molMt−1 h−1 for norbornene vinyl-addition polymerization on treatment with excess methylaluminoxane (MAO). The parameters of the reaction conditions, the type of metals and steric effects of coordinative ligands had influences on the catalytic properties. C2 was selected as a catalyst precursor for the copolymerization of norbornene (NB) with 2-butyloxymethylene norbornene (BN), which exhibited catalytic activities up to 1.1 × 105 gpolymer molPd−1 h−1 and produced copolymers with relatively high molecular weights. The fraction of BN in the copolymer could reach up to 9.8–62.1% by controlling the monomer feed ratio range from 10–80%. The achieved vinyl-addition type poly(NB-co-BN) displayed high thermal stability and was soluble in common organic solvents, such as CHCl3 and THF.
研究领域:
高分子化学
·
配位化学
·
催化化学
·
有机金属化学
·
功能高分子材料
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2023
·Vol. 30
·期 11
·1-10
·
IF 2.8
Yuan Ming,Wang Huan,Huang Dayun,Zhang Hao,Chen Jing
In this paper, the polymerization of butyl acrylate (BA) in the presence of palladium nanoparticles (Pd NPs) has been investigated. A series of organic halides such as carbon tetrachloride (CCl 4 ), ethyl 2-bromopropionate (EBP), ethyl 2-chloropropionate (ECP) and ethyl α-bromophenylacetate (α-EBP) were employed to initiate the polymerization of BA in the presence of Pd NPs. An ultrahigh molecular weight poly(butyl acrylate) (PBA) with a number average molecular weight ( M n ) up to 1.86 × 10 6 Da and polydispersity index (PDI) of 2.38 was synthesized by using α-EBP as an initiator in the presence of 10.5 ppm of Pd NPs at 60 ºC. The orders of polymerization with respect to α-EBP, Pd NPs and BA were determined to be 0.48, 0.86, and 0.95 respectively according to the kinetic investigation. A mechanistic investigation revealed that the reaction of α-EBP and Pd NPs resulted in a generation of α-EBP residue radical to initiate the polymerization of BA around the surface of Pd NPs.
研究领域:
高分子化学
·
纳米技术
·
材料科学
·
有机化学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2021
·
IF 6.901
Jun-Ren Qu,Zi-Rui Yang,Jing Wang,Zi-Li Liu,Chang-Wei Xu
Designing appropriate support for noble metal-based catalyst has consistently been an effective strategy to improve the catalytic activity of ethanol electrooxidation reaction (EOR). Here, a novel heteroatom-doped carbon (HDC) material has been prepared by calcination of Schiff base metal complex precursor. The HDC-750 prepared at the optimum temperature (750 °C) has a three-dimensional structure with large specific surface area and unique pores. When the HDC-750 is used as a support for palladium nanoparticles , it can improve the conductivity of catalysts, the permeability of electrolyte and intermediates, and increase the number of anchoring points of palladium nanoparticles . Due to its unique three-dimensional structure and the synergistic enhancement effect of strong metal support interaction between Pd and HDC-750, the Pd/HDC-750 catalyst exhibits high electrochemical active surface area (23.94 m 2 g Pd −1 ) and excellent EOR activity (146.3 mA cm −2 ), which is as high as 2.1 and 3.0 times of that for the Pd/C. After 3600 s durability test, the Pd/HDC-750 shows a high current density of 9.9 mA cm −2 , while Pd/C shows only 1.3 mA cm − 2 .
研究领域:
材料科学
·
催化化学
·
电化学
✓ 已验证
DOI
高影响因子
Frontiers of Materials Science
·
2022
·Vol. 16
·期 4
·1-9
·
IF 2.612
Zhu Chaoqi,Li Xiang,Wang Xiaoxia,Su Huiyu,Ma Chaofan,Guo Xiang,Xie Changsheng,Zeng Dawen
Efficient chemical warfare agents (CWAs) detection is required to protect people from the CWAs in war and terrorism. In this work, a Pd-doped SnO 2 nanoparticles-based gas sensor was developed to detect a nerve agent simulant named methyl salicylate. The sensing measurements of methyl salicylate under different Pd doping amounts found that the 0.5 at.% Pd-doped SnO 2 exhibited a significant improvement in the detection of methyl salicylate at the ppb (1 ppb = 10 −9 ) level, and the response value to 160 ppb methyl salicylate is 0.72 at 250 °C. Compared with the pure SnO 2 , the response value is increased by 4.5 times, which could be attributed to the influence of the noble metal Pd on the oxygen state and its catalytic effect. In addition, the 0.5 at.% Pd-doped SnO 2 sensor still has an obvious response to 16 ppb methyl salicylate with a response value of 0.13, indicating the lower detection limit of the sensor.
研究领域:
材料科学
·
化学传感器
·
纳米技术
·
环境监测
✓ 已验证
DOI
高影响因子
ACS Nano
·
2014
·
IF 12.033
Liuyi Li,Huaixia Zhao,Jinyun Wang,Ruihu Wang
Two click-based porous organic polymers (CPP-1 and CPP-2) are readily synthesized through a click reaction. Using CPP-1 and CPP-2 as supports, palladium nanoparticles (NPs) with uniform and dual distributions were prepared through H2 and NaBH4 reduction routes, respectively. Ultrafine palladium NPs are effectively immobilized in the interior cavities of polymers. The coordination of 1,2,3-triazolyl to palladium and the confinement effect of polymers on palladium NPs are verified by solid-state 13C NMR and IR spectra, XPS analyses, EDX mapping, and computational calculation. The steric and electronic properties of polymers have a considerable influence on the interaction between polymers and palladium NPs, as well as the catalytic performances of NPs. The ultrafine palladium NPs with uniform distribution exhibit superior stability and recyclability over palladium NPs with dual distributions and palladium on charcoal in the hydrogenation of nitroarenes, and no obvious agglomeration and loss of catalytic activity were observed after recycling several times. The excellent performances mainly result from synergetic effects between palladium NPs and polymers.
研究领域:
材料化学
·
纳米催化
·
有机合成
·
高分子科学
·
物理化学
✓ 已验证
DOI
高影响因子
ChemSusChem
·
2018
·Vol. 11
·期 15
·2593-2603
·
IF 7.411
Jingwei Li,Bo Wei,Xing Yue,Zhe Lü
The low performance and insufficient catalytic activity of perovskite anodes hinder their further application in intermediate-temperature solid-oxide fuel cells (IT-SOFCs). A novel La 0.8 Sr 0.2 Fe 0.9 Nb 0.1 Pd 0.04 O 3− δ (LSFNP) anode material has been developed with Fe–Pd co-exsolutions for IT-SOFCs. Fe 0 and Pd 0 metallic nanoparticles are confirmed to exsolve on the surface of the perovskite anode during operation under a hydrogen atmosphere. The introduced Pd exsolutions promote the charge-transfer process slightly and the H 2 -adsorption ability of the La 0.8 Sr 0.2 Fe 0.9 Nb 0.1 O 3− δ (LSFN) parent anode significantly, as metallic Pd is a conductor with excellent catalytic activity and an absorber of hydrogen that can absorb a large amount of H 2 by forming unstable chemical bonds. A single cell with the LSFNP anode exhibits high output performance (maximum power density of 287.6 mW cm −2 at T =800 °C by using humidified H 2 as the fuel), excellent redox stability, and considerable coking and sulfur tolerances. After the introduction of Pd exsolutions, the increase in the electrochemical performance is more significant under low H 2 concentrations and at low temperatures with a maximum power density ratio of the LSFNP anode cell/LSFN anode cell reaching 18 under 5 % H 2 /argon at T =650 °C. Pd-decorated LSFNP is a high-performance, redox-stable, coking-tolerant, and sulfur-tolerant anode material for IT-SOFCs, making Pd exsolution a reliable nanodecoration strategy to improve the low kinetics of perovskite anodes. Graphical Ex marks the spot : The La 0.8 Sr 0.2 Fe 0.9 Nb 0.1 Pd 0.04 O 3− δ (LSFNP) anode material with Fe–Pd co-exsolutions for intermediate-temperature solid-oxide fuel cells is prepared. The exsolved Fe 0 and Pd 0 co-exsolutions promote the charge-transfer process and H 2 -adsorption ability of the La 0.8 Sr 0.2 Fe 0.9 Nb 0.1 Pd 0.04 O 3-δ (LSFNP) anode. LSFNP anode exhibits high performance, good redox-stability, good coking and sulfur tolerance. A maximum power density of 287.6 mW cm −2 is obtained at 800 °C using humidified H 2 as the fuel. SDC=Sm 0.2 Ce 0.8 O 2− δ .
研究领域:
材料科学
·
能源化学
·
电化学
·
功能材料
·
催化化学
✓ 已验证
DOI
高影响因子
Science China-Materials
·
2023
·Vol. 66
·期 5
·1810-1819
·
IF 8.1
Xiao Hongbin,Qian Qingkai,Zang Zhigang
Recently, all-inorganic cesium lead halide (CsPbX 3 (X = Cl, Br, and I) perovskite nanocrystals (NCs) have been extensively investigated for photocatalytic carbon dioxide (CO 2 ) reduction reaction (CO 2 RR). However, because the pristine CsPbX 3 NCs suffer from severe radiative recombination, it is imperative to elaborately design heterostructures to separate electron-hole pairs for achieving efficient CO 2 RR. Herein, palladium (Pd) nanoparticles (NPs) are anchored on CsPbBr 3 NCs by a photo-assisted approach for the first time. The as-prepared CsPbBr 3 @Pd NCs not only build Schottky junctions at the CsPbBr 3 /Pd interfaces that promote the carrier separation and suppress the radiative recombination, but also exhibit lower energy barriers for photocatalytic CO 2 RR than pristine CsPbBr 3 NCs according to the density functional theory calculations. The electron consumption rate reaches a striking peak of 46.2 µmol g −1 h −1 by using CsPbBr 3 @Pd NCs as photocatalysts for CO 2 RR, which is 4.8-fold of the counterpart of pristine CsPbBr 3 NCs. This work not only presents a photo-assisted strategy for anchoring Pd NPs on CsPbBr 3 NCs, but also demonstrates the great potential of using CsPbBr 3 @Pd NCs for photocatalytic CO 2 RR.
研究领域:
材料化学
·
光催化
·
纳米材料
·
环境化学
·
能源化学
·
半导体物理
·
催化化学
✓ 已验证
DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2011
·Vol. 212
·期 21
·2378-2388
·
IF 2.437
Bin Yuan,Xiaohui He,Yiwang Chen,Kaiti Wang
Covalently immobilized silica-supported acetylacetonate dichloride palladium(II) precatalyst is prepared by the reaction of silica particles grafted acetylacetonate ligand further exchange with [Et 4 N] 2 PdCl 4 . The silica-supported catalyst is used in slurry polymerizations of norbornene (NB) to afford a highly productive NB addition polymerization system in combination with B(C 6 F 5 ) 3 cocatalyst. It exhibits productivity of 84 kg of PNB (mol Pd) −1 h −1 at the initial activity, and the catalyst deactivation kinetics in the early stage of polymerization are fitted well by the first-order deactivation kinetics. The obtained vinyl-type polynorbornene is confirmed to be nanosilica hybrid PNB nanocomposite by SEM, TEM with an energy dispersive spectrometer, TGA, and XRD.
研究领域:
高分子化学
·
纳米复合材料
·
催化化学
·
有机金属化学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2023
·
IF 3.6
Zi-Heng Zhang,Li-Jun Han,Shuang-Shuang Ma,Yi-Ran Du,Zheng-Kun Yu,Jin-Qing Lin,Bao-Hua Xu
The Pd(cod)Cl2-catalyzed alkoxycarbonylation of conjugated dienes to β,γ-unsaturated esters was approached by both intramolecular phosphinesulfonate L1 and intermolecular PPh3/PTSA in this study. However, the poor solubility of the Pd/L1 complex and the labile monodentate Pd/PPh3 structure restricts the system efficiency, especially for the scale-up application. By contrast, the stable and well-soluble bidentate Xantphos system allows for the quantitative formation of 3-pentenoate (96%) on a gram scale within 6 h in weakly alkaline N-methylpyrrolidone (NMP), which also functions as a basic site to promote the rate-limiting alcoholysis step while reducing the dosage of ligand to a theoretical value.
研究领域:
有机化学
·
催化
·
合成化学
✓ 已验证
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2021
·
IF 8.198
Ran Zhang,Liye Zhu,Xuan Liu,Jiayin Zhu,Yan Zhao
Owing to the increasing energy demands, direct small-molecule fuel cells, such as ethanol and formate fuel cells, have attracted great attention. During the operation of the fuel cell, noble metal catalysts are widely used to accelerate the reaction kinetics by alloying with other materials. However, there are a few facile methods for improving elemental metal catalytic activity. In this work, the defect-rich palladium (Pd) aerogels are acquired by laser ablating technology, which can significantly improve the intrinsic activity of Pd elementary catalysts through introducing defects and lattice strain. The electrochemical results show that the mass and specific activities of the obtained Pd aerogel for the formate oxidation reaction are 2.26 and 1.99 times higher than those of the commercial Pd/C. The excellent activity and stability of the Pd aerogel for ethanol oxidation reaction have also been demonstrated. The effect of the compressive strain is further investigated by density functional theory (DFT) calculations. It has been found that the compressive strain weakens the adsorption strength of the intermediates, which can facilitate the desorption of toxic specifics. The laser-assisted synthesis of defect-rich aerogel paves a way in optimizing the structure of the elemental metal catalysts and improving their intrinsic catalytic activity.
研究领域:
材料科学
·
电化学
·
催化
·
燃料电池
✓ 已验证
DOI
高影响因子
ChemCatChem
·
2019
·Vol. 11
·期 20
·5098-5107
·
IF 4.495
Ning Xiang,Yaqin Hou,Xiaojin Han,Yulin Li,Yaoping Guo,Yongjin Liu,Zhanggen Huang
Room temperature HCHO catalytic oxidation over inert support loaded Pd catalysts remains a significant challenge. Herein, a series of alkali Na (1–4 wt.%) modified 1Pd/SBA-15 catalysts were prepared by a co-impregnation method and used for HCHO catalytic oxidation at room temperature. Results showed that alkali Na significantly improved the HCHO oxidation performance of 1Pd/SBA-15 and the optimal Na loading was 2 wt.%. BET, XRD, STEM, XPS, H 2 -TPR, O 2 -TPD and in situ DRIFTS were performed to reveal the promotion role of alkali Na. As a consequence, alkali Na addition could stabilize well dispersed Pd particles which then facilitated the O 2 activation and accelerated the decomposition of formate intermediates species, thus a superior HCHO catalytic oxidation performance was obtained. This study first clearly illustrated the promotion mechanism of alkali Na without the implication of active support and provides an efficient and facile way to achieve high dispersion of Pd particles on inert support and tremendously expands the selected range of supports for room temperature HCHO catalytic oxidation. Graphical Alkali promoted : A series of Na alkali-promoted 1Pd/SBA15 catalysts were prepared by a co-impregnation method and tested for HCHO catalytic oxidation at room temperature. Addition of alkali Na stabilized well-dispersed Pd particles which facilitated O 2 activation and accelerated formate species decomposition rate, leading to superior HCHO catalytic oxidation performance of 2Na-1Pd/SBA-15.
研究领域:
催化化学
·
环境科学
·
材料化学
·
表面科学
·
大气污染控制
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2018
·Vol. 43
·期 45
·20712-20720
·
IF 4.229
Biyao Jin,Yiqi Li,Lianhua Zhao
Bimetallic PdV/C nanoparticles have been synthesized by phase-transfer method for catalyzing the oxygen reduction reaction (ORR) in alkaline electrolytes . PdV/C nanoparticles with different V contents are spherical with a mean diameter of 3–4 nm, and the addition of V expands the lattice parameter of Pd as shown by XRD . XPS analysis indicated the binding energy of Pd 0 3d peak increased by ca. 1 eV. Density functional theory (DFT) calculations results shows d-band center of Pd down-shift after V-doping. Based on the electrocatalytic results, introducing V can improve the catalytic activity for ORR, methanol crossover tolerance and stability. Especially, Pd 4 V/C shows higher initial potential (E onset = 1.027 V), excellent methanol crossover tolerance (98.03% retained) and long-term stability (81.30% retained), which are comparable with Pt/C JM . This work provides a new method of synthesizing PdV/C nanoparticles , which have the potential to be used as the cathode electrocatalysts for fuel cells.
研究领域:
材料科学
·
电化学
·
纳米催化
·
能源材料
·
燃料电池
·
物理化学
·
表面科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）