Catalysts
·
2016
·Vol. 6
·期 2
·19
·
IF 2.964
Guozhu Liu,Yunxia Zhao,Jinhua Guo
High selectively catalytic conversion of lignin-based phenols (m-cresol,p-cresol, and guaiacol) intopara-/m-xylene was performed over Pt/HZSM-5 through hydrodeoxygenation andin situmethylation with methanol. It is found that thep-/m-xylene selectivity is uniformly higher than 21%, and even increase up to 33.5% form-cresol (with phenols/methanol molar ratio of 1/8). The improvedp-/m-xylene selectivity in presence of methanol is attributed to the combined reaction pathways: methylation ofm-cresol into xylenols followed by HDO intop-/m-xylene, and HDO ofm-cresol into toluene followed by methylation intop-/m-xylene. Comparison of the product distribution over a series of catalysts indicates that both metals and supporters have distinct effect on thep-/m-xylene selectivity.Keywords:m-cresol;hydrodeoxygenation;methanol;p-/m-xylene;methylation
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2016
·Vol. 8
·期 25
·12812-12818
·
IF 7.76
Zhuoqing Lin,Wenlong Chen,Ying Jiang,Ting Bian,Hui Zhang,Jianbo Wu,Yong Wang,Deren Yang
PtRu bimetallic particles are well-known commercial catalysts with promising performance for methanol oxidation. However, shape-controlled synthesis of PtRu bimetallic nanocrystals, especially for the platonic structures with {100} (e.g., cubes) or {111} facets (e.g., icosahedra) exposed towards catalysis, has met only limited success due to the different crystal structures of Pt and Ru. Here we report a facile approach to the synthesis of Ru decorated Pt bimetallic cubes and icosahedra in a mixed solvent. We found that the cubes were formed in the solvent containing N,N-dimethylmethanamide (DMF) and oleylamine (OAm) possibly due to the selective adsorption of CO on Pt{100} arising from the decomposition of DMF catalyzed by a Ru salt precursor. When hexadecane was added into the aforementioned solvent, the synthesis became a two-phase interfacial reaction due to the large difference in solvent polarity, thereby retarding the reaction kinetics and promoting the formation of the icosahedra with the composition similar to the cubes. When evaluated as catalysts towards methanol oxidation, the Ru decorated Pt icosahedra showed much better performance in terms of specific and mass activity relative to the corresponding cubes. Specifically, the Ru decorated Pt bimetallic icosahedra achieved a specific activity of 0.76 mA cm−2 and mass activity of 74.43 mA mgPt−1, which is ∼6.7 and 2.2 times as high as those of the carbon supported Pt7Ru nanoparticles, respectively. This enhancement can be attributed to a combination of twin-induced strain and facet effects.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 79
·75384-75389
·
IF 3.289
Liang-Liang Wu,Li-Ying Wang,Zheng-Jun Xie,Feng Xue,Chi-Fang Peng
This paper reported that the peroxidase-like activity of DNA–Ag/Pt nanoclusters (NCs) can be inhibited selectively by Hg2+. The interaction between Hg2+ and the DNA–Ag/Pt NCs was discussed through characterization by TEM, DLS and XPS, etc. It was found that the integration of both Hg0 and Hg2+ to the DNA–Ag/Pt NCs resulted in the DNA–Ag/Pt NCs aggregation and the decrease of Pt2+ content on the DNA–Ag/Pt NCs surface, which finally impaired their catalytic activity. Based on the above mechanism, a colorimetric detection for Hg2+ was developed with a detection limit (LOD) of 5.0 nM and a linear range from 10 nM to 200 nM. The method was highly selective toward Hg2+ over other common metal ions, low-cost and simple, which facilitated the application of detecting Hg2+ in tap water.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2016
·Vol. 4
·期 32
·12630-12637
·
IF 8.262
Jianjun Ding,Xiangyang Li,Lin Chen,Xian Zhang,Song Sun,Jun Bao,Chen Gao,Xingyou Tian
Au–Pt/CaIn2S4 composites were synthesized for the first time using the photoreduction method by which bimetallic Au–Pt alloy nanoparticles were in situ site-selectively photoreduced on the edges of monoclinic CaIn2S4 nanosteps. The Au–Pt alloy nanoparticles as cocatalysts can spatially separate the oxidation and reduction sites and effectively enhance the photocatalytic hydrogen activity of CaIn2S4 under visible light irradiation. When introducing 0.5 wt% Au–Pt alloy nanoparticles, the rate of hydrogen production could reach 107.6 μmol h−1, which was higher than that of CaIn2S4, Au/CaIn2S4 and Pt/CaIn2S4 by a factor of 18.3, 2.37 and 2.4, respectively. The enhanced photocatalytic activity for hydrogen production could be attributed to the low recombination efficiency of the photogenerated charges and surface-plasmon-resonance-induced effect of Au nanoparticles.
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2017
·Vol. 184
·期 7
·2031-2038
·
IF 4.58
Shao Fengying,Jiao Lei,Wei Qin,Li He
The interference by dissolved oxygen is an obstacle in electrochemical immunoassays. The authors are reporting here on a method that employs a working potential that is below the reduction potential for oxygen and hence is not interfered by oxygen/air. Ternary Pt-Co-Cu nanodendrites were prepared by a one-pot reaction. They were placed on a glassy carbon electrode (GCE) modified with gold nanoparticles (AuNPs) where they showed excellent catalytic activity toward the reduction of hydrogen peroxide at a reduction potential of −0.015 V (vs. SCE). Dissolved oxygen, in contrast, is not reduced at this potential. In order to obtain a sandwich-type of voltammetric immunosensor, antibody against insulin (Ab 1 ) immobilized on the AuNPs on the GCE. The secondary antibody (Ab 2 ) was labeled with Pt-Co-Cu nanodendrites as signal marker for signal amplification. After adding hydrogen peroxide, its catalytic oxidation by the immunosensor depends on its loading with insulin. Hence, insulin can be quantified due to the positive correlation that exists between current and the concentration of ternary Pt-Co-Cu nanodendrites on the electrode. The sensor has a linear response in the 0.2 pM to 2 nM insulin concentration range, with a 0.08 pM detection limit. The assay is well reproducible, acceptably selective, and the sensor is fairly stable over time.
One-pot synthesis of ternary Pt-Co-Cu nanodendrites for oxygen interference-free electrochemical detection of insulin. GCE (glassy carbon electrode). Pt-Co-Cu NP (Pt-Co-Cu nanoparticles). BSA (bovine serum albumin). Ab 1 (coating antibody). Ab 2 (labeling antibody). The sandwich-type electrochemical immunosensor has been used for detecting insulin with high sensitivity, which is based on Au nanoparticles for biomolecular immobilization and the one-pot synthesis of ternary Pt-Co-Cu nanodendrites as label enhancer.
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Rongrong Yang,Jun Zhou,Yuanqing Shi,Yafeng Xiao,Lei Wu,Rock Keey Liew,Mu Naushad,Su Shiung Lam
The reconstruction of local electronic states in Pt-O x is an effective strategy for balancing charge distribution and enhancing the intrinsic activity of noble metals. This study presents the use of highly porous and oxygen-rich activated bluecoke powders as a desirable carbon support, and regulates Pt-O x bonds by incorporating the Fe as transition metal, leading to the development of an efficient bluecoke-based electrocatalyst characterized (Fe/Pt–O@MKABC) by exceptionally low Pt loading. The loading amount of Pt in Fe/Pt–O@MKABC is only 0.98 wt%, which is less than the 5% reported for commercial Pt/C catalyst, yet its hydrogen evolution performance is comparable. The developed catalyst presents exciting catalytic ability with overpotential of only 17 mV at 10 mA/cm 2 , a high mass activity of 8.3 A/(cm 2 ·mg pt ) at 50 mV, a large turnover frequency of 8.29 H 2 /s, and outstanding durability with a mere increase of 5 mV over 10000 cycles in acidic electrolyte. Detailed spectroscopic analysis and theoretical calculation results demonstrate that the abundant oxygen on activated bluecoke powders provides an opportunity for the construction of Fe-O y and Pt-O x . The introduction of Fe leads to electron rearrangement in Fe/Pt–O@MKABC, promoting electron transfer and reducing the adsorption free energy of H*, and the interaction between Fe-O y and Pt-O x enhances the hydrogen evolution reaction (HER) performance.
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2024
·
IF 2.7
Shou-Jiang Han,Xue Wang,Bin Zhang,Hong Yuan,Hai Liu,Yi-Hu Ke
In heterogeneous catalytic reactions, the optimization of surface synergy by adjusting noble metal–support interaction remains a significant challenge. In glycerol oxidation reaction (GOR), introducing oxygen vacancies (Ov) through defect engineering to promote electron transfer, and thus, improve catalytic activity is one of the effective methods. In this work, a series of MZrOx solid solution supports (M = Cu, Mn, Fe, Co, Ni, Zn) were prepared by the co-precipitation method. Then Pt nanoparticles (Pt NPs) were loaded onto the MZrOx support by colloidal-deposition method. The supported Pt/MZrOx catalysts were evaluated for GOR under base-free conditions. The results showed that the Pt/CuZrOx catalyst has optimal catalytic performance. The conversion rate of glycerol and the selectivity of glyceric acid reached 90.5% and 71.4%, respectively. Multi-characterization techniques were employed to analyze the physicochemical properties of the catalysts. It was revealed that the incorporation of a certain amount of M-doping could optimize the abundance of oxygen vacancies, Ptδ+ species, redox properties, and surface acid-basic properties of the supported catalysts, while promoting the formation of strong metal–support interactions (SMSIs), thereby synergistically optimizing the performance of catalysts. These results may offer improved insights and methodologies for the rational design of Pt-based catalysts for GOR under base-free conditions.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry B
·
2017
·Vol. 5
·期 48
·9546-9557
·
IF 4.543
Shao-Lu Li,Yaoyi Wang,Jingfang Zhang,Wei Wei,Hua Lu
We describe here a novel targeting polyion complex (Tg-PIC) system for the delivery and intracellular release of cisplatin. Briefly, a guanidinium-pendant Pt(IV)-backboned poly-prodrug termed P(DSP-Gu) is prepared with excellent aqueous solubility, high drug-loading and high potency. To enable prolonged circulation and selective cellular internalization, P(DSP-Gu) is complexed with anisamide-end-capped poly(ethylene glycol)-block-poly(L-phosphotyrosine)-block-poly(L-leucine) (AA-PEG-PpY-PLeu) to yield Tg-PIC via electrostatic coacervation. Tg-PIC is stabilized by hydrogen bonding between phosphate and guanidinium, the PEG corona, and the helical poly(L-leucine) segment forming the hydrophobic core. The anisamide group, a high affinity ligand recognizing the sigma (σ) receptors that are overexpressed on many human malignancies including prostate cancer, is incorporated at the surface of the Tg-PIC for active targeting and efficient internalization. In vitro, the Tg-PICs show targeted and efficient internalization into sigma receptor-positive PC3 cells, and can release toxic Pt(II) species due to the degradation of P(DSP-Gu) under the intracellular reducing conditions. In vivo, the Tg-PICs exhibit superior antitumor efficacy with reduced toxicity. Thus, the system holds considerable promise towards more effective and safe nanomedicine.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 43
·26943-26951
·
IF 3.108
Huajun Zheng,Ping Niu,Zhefei Zhao
Carbon quantum dot sensitized Pt@Bi2WO6/FTO electrodes (simplified as CQDs-Pt@Bi2WO6/FTO) were successfully prepared by loading platinum particles onto Bi2WO6 nanoplates via a photo-deposition method and sensitized carbon quantum dots (CQDs) via a dip-coating method. The photoelectro-catalytic properties of the Pt@Bi2WO6/FTO and CQDs-Pt@Bi2WO6/FTO electrodes for methanol oxidation were investigated. The results indicated that the CQDs-Pt@Bi2WO6/FTO electrode shows higher photoelectro-catalytic activity and better stability than that of the Pt@Bi2WO6/FTO electrode. The higher photoelectro-catalytic performance for methanol oxidation was attributed due to the special synergetic effects between the photocatalytic and electrocatalytic process under solar light irradiation. More importantly, the introduction of CQDs broaden the photoresponse range of the Bi2WO6 material and improves the mobility of the photocarriers. Meanwhile, the doped CQDs act as preferential adsorption sites for the intermediate carbonaceous species during methanol oxidation. This not only alleviates CO poisoning towards the Pt particles, but also improves the efficiency of methanol oxidation by constructing a new type of CQDs-Pt electrocatalyst. The composite material, which combines the dual function of photocatalysis and electrocatalysis will be a promising candidate for new photoelectro-catalytic fuel cells.
✓ 已验证
产品关联
DOI
高影响因子
Polymer Chemistry
·
2017
·Vol. 8
·期 15
·2410-2422
·
IF 5.375
Zihao Zhang,Yongjing Li,Jiaxun Wan,Peihua Long,Jia Guo,Guosong Chen,Changchun Wang
Cisplatin is a widely-used chemotherapeutic drug in the clinic against a range of cancers. However, its anti-cancer efficacy and bioavailability are severely affected by systemic toxicity as well as drug resistance, which are mainly due to indiscriminate body distribution, low tumor accumulation and glutathione (GSH)-related drug detoxification. In this study, we prepared for the first time a new kind of Pt(IV)-crosslinked polymer nanoparticle with small, uniform size and high loading of cisplatin (60.8%). Such a kind of polymer nanodrug could keep its structural integrity during blood circulation to afford higher tumor accumulation via the EPR effect and receptor-mediated targeting effect, yet rapidly self-disintegrate to release drugs in response to tumor intracellular bio-reducing molecules, such as glutathione (GSH), resulting in efficient cancer cell inhibition and reduced systemic toxicity in vivo. Meanwhile, some of the cellular GSH molecules are depleted and transformed into an oxidized GSSG form to decrease their chelating interaction with platinum drugs, which attenuate their detoxifying effect on the Pt(II) species and may have an advantage for overcoming the tumor resistance to cisplatin induced by GSH. Moreover, the maximum tolerated dose of drug could be greatly enhanced (>3 fold), which improved the bioavailability of the nanodrug at relatively high doses. The present work provides a novel drug self-crosslinked design tactic and might open a new window for clinical cancer treatment.
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2024
·
IF 20.2
Ming-Kun Ke,Yuan Min,Shu-Chuan Mei,Hou-Wei Zeng,Zhao-Hua Wang,Tian-Wei Hua,Jie-Jie Chen,Gui-Xiang Huang,Han-Qing Yu
5-Hydroxymethyl-2-furancarboxylic acid (HMFCA) is an important feedstock in chemical and pharmaceutical industries . Its production through aerobic conversion of 5-hydroxymethylfurfural (5-HMF) has promising prospects but is challenged by the over-oxidation. In this work, we develop a refined Pt-Ag co-catalytic strategy to tailor the selectivity of 5-HMF’s aerobic oxidation. By simple in situ addition of AgNO 3 to the thermal catalytic system of Pt nanoparticles , the main products of 5-HMF oxidation could be shifted from 2,5-furandicarboxylic acid (FDCA) to HMFCA with an ultrahigh selectivity of over 99 %. Density functional theory calculations demonstrate that such strategy could alter the HMFCA adsorption sites from Pt to Ag sites and prevent the oxidation of hydroxymethyl group . In addition, this strategy can be extended to other Ag species, such as AgCl, Ag 2 O and AgO. This work provides insights into the Pt-Ag synergistic catalysis and opens up a simple avenue to control the product selectivity for biomass refinement.
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2024
·
IF 4.4
Yumeng Xu,Rongzhou Chen,Hailian Tang,Lu Yan,Fei Huang,Ming Tian,Kaibao Wu,Yanliang Zhou,Jian Lin,Ying Zheng,Xiaodong Wang
Promoting the thermal stability of supported noble metal catalysts under harsh conditions remains challenging for the modern chemistry industry. Herein, Fe-substituted hexaaluminate supported Pt catalysts (Pt/BaFeAl11O19) were synthesized and treated with high temperature at 800 °C under different atmospheres. The Pt particles showed severe sintering under an oxidative atmosphere but high stability under reductive conditions. Interestingly, Pt/BaFeAl11O19 pre-reduced at high temperature possessed improved anti-sintering ablility during oxidative annealing. The characterization results demonstrate that oxygen vacancies were facilely formed under an H2 atmosphere to favor the formation of coating layers on Pt nanoparticles. This structure helps retain oxygen vacancies during subsequent oxidative calcination, contributing to promoted stability. The high thermal stability of Pt particles coupled with the easy generation of Fe2+ sites in Pt/BaFeAl11O19 resulted in excellent catalytic performance for CO and C3H8 oxidation after cycling hydrothermal aging at 800 °C.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）