DYES AND PIGMENTS
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2017
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IF 3.473
Tiantian Chen,Tingwen Wei,Zhijie Zhang,Yahui Chen,Jian Qiang,Fang Wang,Xiaoqiang Chen
Highly sensitive and selective fluorescent probes 1 and 2 for detection of palladium ions (Pd 2+ ) were synthesized based on excited-state intramolecular proton transfer process (ESIPT) using 2-(2′-hydroxy-)benzothiazole moiety. Different metal ions were used to optimize their sensitivity and selectivity but best results were obtained with Pd 2+ . Probe 1 produced green fluorescence with Stokes shift of about 163 nm upon addition of Pd 2+ , whereas probe 2 displayed red fluorescence with a large Stokes shift of about 217 nm under similar conditions. The detection limits of 1 and 2 to Pd 2+ were found to be 285 nM and 14.6 nM, respectively. Mechanistic aspects of probes 1 and 2 were discussed to account for the optical changes leading to the strong ESIPT fluorescence in very short duration. Furthermore, the portable test strips were also prepared by direct deposition of the probe molecules onto the filter paper to detect the lowest possible ppm levels of Pd 2+ .
研究领域:
分析化学
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材料科学
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DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Ji Wen,Chang Yu,Lin Ni,Qianbing Wei,Xiuchao Yao,Jieshan Qiu
The supported noble metal-based catalysts, which are promising and deliver a high activity for the industrial synthesis of fine chemicals, still face the various issues such as complex preparation steps and migrating or leaching of the metal. Herein, we demonstrate an integrated Pickering emulsion system stabilized by carbon nanotubes (CNTs) after acid treatment to achieve in-situ reduction of Pd 2+ coupling with benzyl alcohol (BA) oxidation. Kinetic analysis confirms the reduction of Pd 2+ to Pd 0 with BA as reductant and the selective oxidation of BA catalyzed by Pd 0 occur simultaneously at the oil–water interface in more details. The homogeneous immobilization of Pd particles on the defects of CNTs and efficient reduction of Pd 2+ in the Pickering interfacial catalysis (PIC) system are also decoupled. Moreover, the in-situ diffuse reflectance infrared-fourier transform spectra (DRIFTS) reveal that the interaction between BA and Pd/CNTs-PIC with water can be enhanced. Benefiting from the enlarged biphasic interface, the Pickering emulsion system achieves a higher efficiency, with a turnover frequency (TOF) of 424 h −1 , representing a 9.5-fold increase compared to the conventional single-toluene system (TOF, 44 h −1 ). The general applicability of the integrated system is also demonstrated over different precursors and supports.
研究领域:
化学工程
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材料科学
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催化反应
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DOI
高影响因子
Catalysis Science & Technology
·
2022
·Vol. 12
·期 12
·3874-3885
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IF 6.177
Ling Zhang,Jikai Sun,Shuchao Jiang,Huijie He,Guoqing Ren,Dong Zhai,Rui Tu,Shengliang Zhai,Tie Yu
This work reported an efficient PdIr/activated carbon (PdIr/AC) catalyst and its application during direct ethane dehydrogenation (EDH) into ethane. The XRD and HADDF-STEM results revealed Pd/Ir nano-particles and atomically dispersed Pd2+ and Ir4+ species simultaneously. The activity tests demonstrated that Ir species showed higher C2H4 selectivity than Pd species and the co-presence of Pd/Ir could further improve the catalytic stability and inhibit carbon deposition over the bimetallic Pd/Ir catalyst. Nevertheless, raising the reaction temperature from 500 °C to 600 °C boosted coking including carbon nanotubes (CNTs) and carbon particles. XPS results of Pd7Ir2/AC-B after Ar or H2 pretreatment proved that the active sites are Pd2+/Ir4+ species. The simulation results exposed the reaction pathway over Ir4+/Pd2+ species, and ethane dehydrogenation was the rate-determining step over the PdIr/AC sample; meanwhile, the synergetic effect between Pd2+ and Ir4+ increased their TOF (C2H4). Finally, a deactivation mechanism was also proposed to examine the coking over various metal species.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
Molecular Catalysis
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2024
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IF 3.9
Jin Zhao,Tianjun Hu,Jinjin Wang,Ying Wang,Junming Zhang,Baoliang Lv,Wanqing Zhang,Jianfeng Jia
Reactive metal-support interaction (RMSI) is an effective means of inducing surface strain and charge transfer in catalysts, which further enhances electrochemical activity and modulates reaction pathways. Nevertheless, the precise synthesis of nanomaterials with tunable strain and unique morphology remains a challenge. In this work, we have synthesized Pd nanoparticles decorated Pd 2+ - doped Co 3 O 4 nanosheets (Pd 7.4% /Co 3 O 4 ) by a NaBH 4 reduction method, which exhibit excellent performance for ethanol oxidation reaction (EOR) and oxygen reduction reaction (ORR). The introduction of the Pd into the Co 3 O 4 by the means of elemental doping and nanoparticle decoration, and the resulting lattice strain and electron redistribution are responsible for the improved performance. Meanwhile, Pd 7.4% /Co 3 O 4 has a relatively low d-band center that reduces the adsorption energy of reaction intermediates to improve reaction selectivity and eliminate EOR toxic intermediates, ultimately promoting reaction kinetics. This work demonstrates a simple and effective strategy to manipulate lattice strain and electronic coupling and provides a novel and advanced way for the development of low-cost and high-quality direct ethanol fuel cells (DEFCs) catalysts.
研究领域:
材料科学
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电化学
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催化反应
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DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2020
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IF 3.232
Wenjun Zhou,Qiang Gao,Darui Liu,Chen Li,Shu Liu,Kaisheng Xia,Bo Han,Chenggang Zhou
A novel salicylaldehyde bis-Schiff-base probe decorated with imidazolium ionic liquid moieties at both ends (SAS-IMIs) was designed and facilely synthesized as a colorimetric/ratiometric sensor to visually detect Cu 2+ and Pd 2+ in pure aqueous media. Due to the positively charged characters of its head and tail, the SAS-IMIs exhibited high water solubility with a potential advantage in minimizing the self-aggregation. More importantly, simply by varying the solution pH, colorimetric/ratiometric sensing detection of individual metal ion (Cu 2+ or Pd 2+ ) was realized without any mutual interference. Subsequently, sensitive, selective, and differential detections for Cu 2+ (LOD: 0.080 μM) and Pd 2+ (LOD: 0.076 μM) in 100% aqueous solutions were achieved, which proved to be applicable for real water samples. Results from density functional theory (DFT) calculations unveiled the Cu 2+ /Pd 2+ -binding properties of SAS-IMIs, which were in accordance with the experimental observations. Furthermore, a SAS-IMIs-based solid phase sensor was fabricated, which manifested satisfactory detection abilities for Cu 2+ and Pd 2+ .
研究领域:
分析化学
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环境科学
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2023
·
IF 4.7
Xin Song,Fangjun Shao,Zijiang Zhao,Xiaonian Li,Zhongzhe Wei,Jianguo Wang
Precise regulation of reaction selectivity at high conversions is the key to non-terminated alkyne semi-hydrogenation. Herein, a support modification strategy was employed to incorporate trace amounts of Mg elements into alumina support. The modified support loaded Pd catalyst optimized the activity and selectivity of the non-terminated alkyne semi-hydrogenation reaction. The TEM and XRD characterization of the catalysts demonstrated the entry of Mg elements into the Al 2 O 3 lattice to achieve the modification of the support. For the 2-butyne-1-ol semi-hydrogenation reaction, the Pd 0.5 /Mg 1 @Al 2 O 3 catalyst showed 99 % conversion and 97 % selectivity of the cis product at hydrogen pressure of 0.1 MPa and 25 °C. The introduced Mg element changed the electronic structure of Pd nanoparticles in the catalyst. The precise regulation of the 2-butyne-1-ol semi-hydrogenation reaction was achieved by adjusting the ratio of Pd 0 to Pd 2+ using the synergistic effect of Pd 0 and Pd 2+ .
研究领域:
催化化学
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材料科学
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2014
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IF 3.84
Qi Huang,Yanmei Zhou,Qingyou Zhang,Enze Wang,Yinghao Min,Han Qiao,Junli Zhang,Tongsen Ma
Based on spirolactam ring-opening reaction, a chromogenic and “off–on” fluorescent sensor for determination of palladium (II) was developed in this paper. The novel sensor was easily synthesized from rhodamine B hydrazide and diacetyl monoxime named RBM. The structure of the sensor has been characterized by ESI-MS and NMR. EDTA-adding experiment indicated that the binding of chemosensor RBM and Pd 2+ was chemically reversible. The fluorescence intensity and absorbance of the sensor showed a good linearity with the concentration of Pd 2+ in the range of 0–15 μM and 0–17 μM, respectively, with detection limits of 0.015 μM and 0.200 μM. Moreover, it has been successfully applied to detect Pd 2+ in palladium-containing catalyst, natural water samples and imaging of Pd 2+ in living cells with satisfying results. The study indicated that this novel sensor could be an attractive approach to detect Pd 2+ in environmental systems and biological systems.
研究领域:
分析化学
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环境科学
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生物无机化学
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分子影像
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化学生物学
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DOI
高影响因子
OPTICAL MATERIALS
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2023
·
IF 3.9
Shuocheng Gao,Hao Zhang,Haiyan Li,Yuansheng Pei
In this work, humic acid-based sulfur-chlorine-doped carbon quantum dots (L-CQDs) were synthesized by using a polyethylene glycol (PEG)-assisted hydrothermal technique using landfill leachate concentrate (LLC) as a carbon source. The prepared L-CQDs contain many oxygen-containing functional groups on the surface with a small average particle size of 4–6 nm, resulting in excellent hydrophilicity and dispensability. The three-dimensional fluorescence spectrum shows that the characteristic peak for humic acid for LLC is redshifted after adding PEG as an inactivator, indicating that L-CQDs are synthesized by PEG encapsulation and linkage. The optimum condition for preparing L-CQDs involves the addition of 0.5 g PEG (MW = 2000) into 20 mL LLC and reaction at 200 °C for 5 h, with the optimal L-CQD quantum yield reaching 5.32%. L-CQDs were used to prepare fluorescent nanoprobes for the detection of palladium ions (Pd 2+ ). The obtained nanoprobe shows admirable performance in detecting Pd 2+ , with high selectivity , excellent water solubility and stability. The fluorescence intensity of the nanoprobe is selectively quenched through static quenching by Pd 2+ in the concentration range of 5–40 μmol L −1 . This work provides a simple, easy, and fast detection method for Pd 2+ and opens up a way for the resource utilization of LLC.
研究领域:
环境科学
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材料科学
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分析化学
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DOI
高影响因子
Catalysis Science & Technology
·
2026
·
IF 4
Yuzhen Hu,Ruiying Xiong,Xin Qu,Taras Nagornyy,Zhenlong Song,Xingye Zeng,Ning Li,Qi Zhang,Longlong Ma
Selective C-C bond cleavage in lignin is a pivotal step toward its efficient utilization, enabling the production of diverse and valuable chemicals from this abundant and renewable resource. Among the catalysts reported for oxidative cleavage of C-C bond in lignin β-O-4 ketones, CeO₂-supported Pd catalysts have demonstrated outstanding activity. However, the exact nature of the active Pd sites responsible for C-C bond cleavage remains poorly understood, limiting mechanistic insights into this transformation. In this study, CeO₂ supports with four distinct morphologies including rods (R), spheres (S), cubes (C), and polyhedrons (P) were synthesized to investigate their influence on the catalytic activity of Pd/CeO₂ catalysts in the oxidative cleavage of β-O-4 ketones. The catalytic performance was found to depend strongly on the morphology of CeO₂, with Pd/CeO₂-P exhibiting the highest activity for C-C bond cleavage. This catalyst possessed the lowest Pd⁴⁺ content and the highest Pd⁰/Pd²⁺ ratio among the series. By systematically tuning this ratio, a volcano-type relationship between Pd⁰/Pd²⁺ ratio and catalytic activity was established, indicating a dual-site mechanism in which Pd⁰ facilitates the formation of reactive oxygen species, while Pd²⁺ serves as the active center for C-C bond cleavage.
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DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2022
·
IF 4.831
Mingyue Chang,Moru Zhang,Haihong Hu,Shucai Liang
A novel polyethyleneimine (PEI)-based polymeric nanosensor (named PEIMP) was developed for specific fluorescence enhanced sensing of Pt 4+ ion in aqueous media. The sensor was fabricated via “one-pot” three-component reaction using ortho -phthalaldehyde (OPA), PEI and mercaptopurine as raw materials, by which the formation of isoindole fluorophore and its chemical grafting onto PEI chain were achieved simultaneously. The morphology, size and structure of PEIMP have been characterized by various techniques. In buffered aqueous solution (pH 7.0), PEIMP had the ability to specifically bind with Pt 4+ producing notable increase in fluorescence emission at 463 nm (excited at 395 nm). Based on investigations on the sensing mechanism, the fluorescence turn-on response towards Pt 4+ was attributed to the binding of Pt 4+ with purine group in PEIMP resulting in the inhibition of photoinduced electron transfer from purine to isoindole fluorophore. Under the optimal conditions (pH 7.0, incubated at 37 ℃ for 20 min) the detection of Pt 4+ could be achieved with the linear range of 0.1–10 μM and the detection limit of 80 nM. The sensor had the advantages of low-cost raw materials, simple and environmental-friendly synthesis and analytical detection procedures. What's more, it could selectively and sensitively detect Pt 4+ without the effects from common transition metal ions (Pb 2+ , Fe 3+ , Cr 3+ , Al 3+ , Ag + , Co 2+ , Hg 2+ , Cd 2+ , Cu 2+ , Mg 2+ , Ni 2+ , Mn 2+ , Zn 2+ ), especially precious metal ions of Pt 2+ and Pd 2+ . The proposed method had been successfully applied to quantify Pt 4+ in wastewater and urine samples, and also proved to be potential for monitoring Pt 4+ in biological systems.
研究领域:
分析化学
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生物医学工程
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DOI
PubMed
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 70
·43175-43186
·
IF 3.119
Jinqiang Tan,Huamei Zhu,Shasha Cao,Sisi Chen,Yuanfu Tian,Dachuan Ding,Xuan Zheng,Chuanqun Hu,Tao Hu,Chonggang Wu
A poly(methyl methacrylate)-supported Pd0 nanocatalyst was successfully prepared from solution reaction of Pd(CH3COO)2 with a copolymer acid, poly(methyl methacrylate-ran-methacrylic acid) (MMA–MAA). The reaction was carried out in a benzene/methanol mixed solvent in the dark at room temperature (∼25 °C) in the absence of a typical chemical reductant. There was coordination between the Pd0 nanoclusters and MMA–MAA, resulting in Pd0 nanoclusters being stably and uniformly dispersed in the MMA–MAA matrix, with an average particle size of ∼2.5 ± 0.5 nm. Mechanistically, it can tentatively be proposed that PMMA-ionomerization of the Pd2+ ions produces intramolecular –2COO−–Pd2+ aggregate cross-links in the solution. On swelling of the chain-segments that are covalently bound via multiple C–C bonds, the resultant elastic forces cause instantaneous dissociation at the O–Pd coordination bonds to give transient bare (i.e., uncoordinated), highly-oxidative Pd2+ ions and H+-associative carboxylate groups, both of which rapidly scavenge electrons and protons, respectively, of the active α-H atoms abstracted from the methanol molecules of the solvent to make Pd0 nanoclusters supported by the re-formed MMA–MAA. The MMA–MAA acid copolymer, without itself undergoing any permanent chemical change, serves as a mechanical activator or catalyst for the mechanochemical reduction of Pd(CH3COO)2 under mild conditions. Compared with traditional Pd/C catalysts, this Pd0 nanocatalyst exhibited more excellent catalytic efficiency and reusability in the Heck reaction between iodobenzene and styrene, and it could be easily separated. The supported Pd0 nanocatalyst prepared using this novel and simple preparation method may display high-efficiency catalytic properties for other cross coupling reactions.
研究领域:
材料科学
·
催化化学
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产品关联
DOI
PubMed
高影响因子
Molecular Catalysis
·
2024
·
IF 3.9
Xiaoying Zhou,Shiyu Fang,Zihao Hu,Zuliang Wu,Jing Li,Wei Wang,Jiali Zhu,Shuiliang Yao,Erhao Gao
This study introduces a novel catalyst system comprising Pd nanoparticles loaded onto Mn-doped NiO for the efficient oxidation of methane (CH 4 ) at low temperatures. The loading of Pd nanoparticles onto the Mn-doped support has yielded a catalyst with exceptional activity and stability, as evidenced by the lowest T 50 temperature of 276 °C and a CH 4 conversion reaching 97% at 325 °C. The catalyst demonstrates optimized reaction kinetics with the lowest activation energy of 69.2 kJ mol –1 . The catalyst's superior performance is attributed to the synergistic effects of the Pd/Mn-NiO composite, which include a higher Pd 2+ /Pd 4+ ratio, increased adsorptive oxygen concentration (O ads /O total ), and a reduced Ni 3+ /Ni 2+ ratio. These characteristics collectively enhance the catalytic activity for CH 4 oxidation. The Mars-van Krevelen mechanism underpins the oxidation process, with Pd 2+ identified as the principal active site for CH 4 adsorption and dissociation. Diffuse reflectance infrared Fourier transform spectroscopy coupled with mass spectrometry elucidates the pathway of surface reactive oxygen species in the formation of key intermediates, such as formates, and underscores the accelerated decomposition of carbonate facilitated by the Pd modification on the Mn-NiO surface. The findings signify a significant advancement in the development of catalysts for environmental and energy-related applications, particularly in the mitigation of CH 4 emissions.
研究领域:
催化
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环境科学
·
能源
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）