RENEWABLE ENERGY
·
2022
·
IF 8.634
Tong Li,Hao Li,Chunli Li
Catalytic removal of oxygen from biomass by hydrodeoxygenation (HDO) as a promising process has been pursued for efficient utilization of biomass resources . Here we report a self-support semi-hollow carbon nanospheres (SHCN) supported palladium (Pd) catalyst for vanillin HDO under mild conditions. The shell-void-core structure of carbon nanospheres originates from the modulation of growth kinetics of resorcinol/formaldehyde resin precursors by a given volume of acetone . Notably, 0.5%Pd/SHCN-60 (acetone of 60 mL) catalyst exhibits >99.9% of vanillin conversion and creosol selectivity under 25 °C and 0.1 MPa of H 2 . The good catalytic results can derive from the self-support hollow carbon support and active metallic Pd. Raman results show that 0.5%Pd/SHCN-60 possesses the most abundant defect carbon (A D1 /A G = 2.02), which leads to the small particle size (mean size of 2.9 nm) and well dispersion (29.5%) of Pd. Higher H 2 -desorption temperature (∼440 °C) of 0.5%Pd/SHCN-60 by H 2 -TPD demonstrates the strong interaction of Pd-defect carbon. The strong interaction favors the hydrogen storage and activation of substrates under low pressure of H 2 and reaction temperature, which improves the hydrogenation and hydrogenolysis . Additionally, the contribution of unique core structure to support the shell to enhance mechanical stability leads to intact morphology of catalyst and stable catalytic performance after reused six times. This investigation can provide a design idea of carbon-based catalysts for mild HDO.
研究领域:
催化化学
·
材料科学
·
可再生资源利用
✓ 已验证
DOI
高影响因子
CHEMICAL PHYSICS LETTERS
·
2018
·
IF 1.686
Fangchen Zhen,Maofei Ran,Wei Chu,Chengfa Jiang,Wenjing Sun
Pd-Fe 3 O 4 hybrid nanostructures were prepared using a simple one-pot hydrothermal method. The prepared materials were characterized by Fourier transform-infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, inductively coupled plasma, N 2 adsorption-desorption, and vibrating sample magnetometry. This self-assembled nanosystem acted as an efficient magnetically recyclable noble metal-based multi-functional nanocatalyst. It showed excellent catalytic activity and stability for the Heck reaction of iodobenzene and styrene under mild conditions. The methods used to prepare the Pd-Fe 3 O 4 catalysts were simple and low-cost, which will be useful for the large-scale development and application of a magnetically recoverable Pd catalyst.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
NANOTECHNOLOGY
·
2022
·Vol. 33
·期 45
·455401
·
IF 3.953
Hongjing Wang,Hongyong Chen,Shuli Yin,Qiqi Mao,Chunjie Li,You Xu,Xiaonian Li,Ziqiang Wang,Liang Wang
Nonmetal doping is a promising strategy to improve electrocatalytic performance of noble metal based catalysts for oxygen reduction reaction (ORR). Herein, we report a facile method to fabricate PdCuBP nanothorn assemblies (PdCuBP NTAs) by co-doping B and P into pre-synthesized PdCu NTAs using NaBH4 and NaH2PO2 as B source and P source, respectively. The metal-nonmetal structure and multi-branched morphology can optimize oxygen adsorption energy and avoid catalyst migration, agglomeration and Ostwald ripening. As such, the obtained PdCuBP NTAs exhibit efficient activity and excellent long-term stability for ORR. This research offers an excellent strategy for co-doping nonmetal elements into metal nanocrystals with controllable composition and structure to improve electrocatalytic ORR performance.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2014
·
IF 4.086
Shaojie Li,Daojian Cheng,Xiangguo Qiu,Dapeng Cao
A core-shell Cu@Pd nanowire with enhanced activity and stability for formic acid oxidation (FAO) was prepared by decorating Pd shell on the surface of Cu nanowire. Detailed characterization (XRD, TEM and HAADF-STEM) results confirm that the prepared nanowires are of Cu@Pd core-shell structure with enlarged surface areas. The catalytic activity of Cu@Pd/C (2197.88 mA/mg at 0.257 V) toward FAO is about 4 times higher than that of the commercial Pd/C (547 mA/mg at 0.257 V). The enhanced activity of the catalyst may mainly result from the synergetic effect of Cu and Pd, which was confirmed by density-functional theory (DFT) calculations.
研究领域:
材料科学
·
电化学
·
理论计算
✓ 已验证
DOI
高影响因子
ACTA PHYSICO-CHIMICA SINICA
·
2023
·
IF 10.9
Haoyu Sun,Dun Li,Yuanyuan Min,Yingying Wang,Yanyun Ma,Yiqun Zheng,Hongwen Huang
In recent years, Cu-based multi-metallic nanocrystals with controlled elemental distributions have been extensively studied for potential applications as electrocatalysts for CO 2 reduction reaction (CO 2 RR). Modifying Cu electrocatalysts with secondary or additional metals offers a viable approach to manipulate the overall d -band structure which would cause the shift in the d -band center. Such manipulation can affect the surface affinity of Cu towards key intermediates and thus the following catalytic pathway. Apart from endeavors to adjust the electronic structure, morphological engineering provides effective avenues to enhance the electrocatalytic performance of CO 2 RR. In contrast to quasi-spherical particles with irregular shapes, a 3D-assembled porous structure utilizing 2D nanosheets as building blocks offers advantages such as maximizing surface atom exposure and creating numerous diffusion channels and reactive sites for intermediates formed during catalysis. Yet, it is technique challenging to construct such type of nanoarchitecture via a rationally-design synthetic routes and traditional stepwise self-assembling strategy is time-consuming and lack of versatile control over the structural parameters of resulting products. Therefore, it holds significant value to develop a synthesis method capable of yielding high-purity formations of unique nanostructures. These structures should possess accurately controlled elemental compositions and electronic configurations, and establish a potential correlation between structural benefits and enhanced electrochemical performance in CO 2 RR. Herein, we report the controlled synthesis of palladium-copper-silver (Pd-Cu-Ag) nanocrystals with rationally-designed two-dimensional (2D)-three-dimensional (3D) hybrid architectures and validated with the promising use for electrochemical CO 2 reduction (CO 2 RR). The synthetic procedure includes the conversion of Au@Cu x O nanospheres into CuAg hierarchical nanoflowers (HNFs), as directed by the capping agent octadecyltrimethyl ammonium chloride. Interestingly, the nanosheets are formed in situ as the building block. Following galvanic replacement reaction between CuAg HNFs and Na 2 PdCl 4 removes Ag and Cu, introduces zero-valent Pd, and creates abundant pores on the nanosheets. These CuAg-based products are tested as CO 2 RR electrocatalysts, in which the Pd 0.7 Cu 40.0 Ag 59.7 PHNFs displayed the optimized performance in terms of C 2+ products selectivity (69.5%) and C 2+ partial current density (−349.1 mA·cm −2 ). As revealed by density functional theory (DFT) simulations, PdAgCu surface has distinct electronic property, which lower the reaction barrier for C-C coupling, protruding the exceptional advantage of the Pd doping towards CuAg electrocatalysts for CO 2 reduction. The present study offers a straightforward approach to fabricate hierarchical multi-metallic nanostructures with the porous nanosheet as building block, and validates its structural advantage in electrocatalysis, shedding light on the rational design of efficient CO 2 RR catalyst. Download: Download high-res image (72KB) Download: Download full-size image
研究领域:
材料科学
·
电化学
·
催化科学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Zhe Su,Shunyan Ning,Zengyuan Li,Shichang Zhang
A silica-polymer-based adsorbent ( iso Pentyl-BTBP/SiO 2 -P) was prepared via a vacuum impregnation method for efficient and continuous separation of palladium from complex systems. The results revealed that the distribution coefficient ( K d ) value of iso Pentyl-BTBP/SiO 2 -P toward Pd in 3 M HNO 3 solution was 5226 mL/g, with a maximum adsorption capacity of 31.7 mg/g. Besides, iso Pentyl-BTBP/SiO 2 -P exhibited a superior adsorption selectivity toward Pd to the other 14 coexisting interfering fission product ions, with the separation factor SF Pd/M value over 433 in 0.1–6 M HNO 3 solution. Moreover, column experiments results demonstrated that iso Pentyl-BTBP/SiO 2 -P can efficiently separate Pd with approximately 100% recovery, from simulated high level liquid waste (HLLW) solutions with multiple competing ions. Finally, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy analysis results revealed strong interactions between nitrogen-containing functional groups (C-N C) and Pd throughout the adsorption process , wherein the NO 3 − acting as the counterions to balance the charge. In conclusion, iso Pentyl-BTBP/SiO 2 -P has shown promising applications for effectively separating Pd from multi-component and highly acidic environments.
研究领域:
化学工程
·
核化学与放射化学
✓ 已验证
DOI
高影响因子
NANOTECHNOLOGY
·
2018
·Vol. 29
·期 33
·335402
·
IF 3.404
Yiqun Jiang,Man Chen,Yifan Yang,Xuanlin Zhang,Xuezhang Xiao,Xiulin Fan,Chuntao Wang,Lixin Chen
Safe and efficient hydrogen storage is one of the key technologies for the widespread utilization of hydrogen energy. Formic acid (FA) is regarded as a safe and convenient chemical hydrogen storage material. However, the lack of highly efficient heterogeneous catalysts hinders its practical application. Herein, we presented a facile wet-impregnated deposition method to synthesize ultrafine AuPd alloy nanoparticles anchored on TiO2 nanosheets (AuPd/TiO2 nanosheets) which were used as high efficient catalysts for the dehydrogenation of FA. TiO2 nanosheets were calcined at different temperatures to modify the catalytic activity of catalyst. AuPd/TiO2 nanosheets-400 exhibits the superior activity for catalyzing the FA to release 96% of overall hydrogen content with an initial turnover frequency value of 592 mol H2 mol−1 metal h−1 at 25 °C and low activation energy of 11.8 kJ mol−1. Detailed characterizations show that the superior catalytic performance can be ascribed to the alloy structure of AuPd centers, the phase and crystallinity of TiO2 nanosheets, and the strong electron transfer interaction between AuPd nanoparticles and TiO2 nanosheets substrate.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
Chemistry-An Asian Journal
·
2021
·Vol. 16
·期 9
·1130-1137
·
IF 4.568
Ling Shen,Jie Ying,Ge Tian,Mingpu Jia,Xiao-Yu Yang
Graphical A facile solvothermal method is presented to synthesize ultralong PtPd alloyed nanowires anchored on graphene as highly effective MOR catalysts. The rational synthesis of Pt-based alloyed nanowires still remains a great challenge because of the different reduction potentials between Pt and another metal and the intrinsic feature of isotropic growth in face-centered cubic (fcc) structured Pt. In this work, PtPd alloyed nanowires with ultrahigh aspect ratio anchored on graphene (PtPd NWs/graphene) were synthesized by a facile solvothermal method without the use of any templates or surfactants. Due to the integration of ultralong PtPd nanowires and stable graphene support, PtPd NWs/graphene exhibited outstanding electrochemical activity toward methanol oxidation reaction (MOR) in comparison with pure Pt NWs/graphene and commercial Pt/C catalysts. Meanwhile, PtPd NWs/graphene had a much higher current density than Pt NWs/graphene and commercial Pt/C catalysts at a constant potential for 7200s in alkaline methanol solution. Moreover, after 1000 cycles of durability testing, PtPd NWs/graphene retained 89.2% of its initial mass activity, much superior to the 63.7% retained for commercial Pt/C.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2021
·Vol. 39
·期 10
·2745-2754
·
IF 6
Yinbing Tian,Zijie Tang,Yu Ru,Yuanyuan Wang,Liyi Dai
Main observation and conclusion Three diamines (1,8-diaminooctane/ p -phenylenediamine/biphenylenediamine) with different alkyl groups were used to synthesize the functionalized graphene networks. Pd as the common metal catalyst was used to explore the effects of alkyl types of diamines on anti-stacking, metal anchoring ability of functional graphene and hence the catalytic performance. The results were discussed by characterization of the material and its catalytic properties. All catalysts showed excellent catalytic performance on the Suzuki cross-coupling reaction with a high yield of up to 100%. The p -phenylenediamine and biphenylenediamine functionalized graphene with larger specific surface area was beneficial to improve the stability of the graphene catalyst and maintain good catalytic activity after 5 cycles. The Pd nanoparticles in 1,8-octanediamine materials have smaller size and a smaller loading with the same or even better catalytic performance than p -phenylenediamine, biphenylenediamine materials, due to the stronger electron donating ability of N of octanediamine than that of p -phenylenediamine.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
ChemCatChem
·
2019
·Vol. 12
·期 5
·1376-1384
·
IF 4.495
Wen-Di Guo,Lei Liu,Shu-Qing Yang,Xiao-Chao Chen,Yong Lu,Giang VO-Thanh,Ye Liu
Graphical Synergetic catalysis : The one-pot tandem bis-alkoxycarbonylation of alkynes was accomplished over the bi-functional catalytic system containing Xantphos-modified Pd-complex and Lewis super-acid of Al(OTf) 3 . Via the synergetic catalysis, the involved Xantphos-modified Pd-complex was responsible for the activation of CO and the alkynes through coordination to Pd-center while Al(OTf) 3 was in charge of the activation of the alcohol to facilitate the formation of [Pd−H] + active species. Tandem bis-alkoxycarbonylation of alkynes allows for the preparation of 2-substituted succinates from alkynes and nucleophile alcohol via two successive alkoxycarbonylation with advantages of 100 % atomic economy and simplified one-pot operation. Herein, the one-pot tandem bis-alkoxycarbonylation of alkynes was accomplished over the bi-functional catalytic system containing Xantphos-modified Pd-complex and Lewis super-acid of Al(OTf) 3 . It was found that, via the synergetic catalysis, the involved Xantphos-modified Pd-complex was responsible for the activation of CO and the alkynes through coordination to Pd-center while Al(OTf) 3 was in charge of the activation of the alcohol to facilitate the formation of [Pd−H] + active species. The in situ high-pressure FT-IR analysis, coupled with 1 H/ 13 C NMR spectral characterizations, confirmed that the introduced Al(OTf) 3 with intensive oxophilicity (via acid-base pair interaction) was able to activate nucleophilic MeOH to be a reliable proton-donor ( i. e . hydride-source) to warrant the formation and stability of [Pd−H] + species upon the oxidation of Pd 0 by H + (Pd 0 +H + →[Pd II −H] + ). Over the developed bi-functional catalytic system, the yields of the target diesters were obtained in the range of 36∼86 % in this sequence with the wide substrate scope.
研究领域:
有机化学
·
催化化学
✓ 已验证
DOI
高影响因子
MONATSHEFTE FUR CHEMIE
·
2023
·Vol. 154
·期 2
·215-222
·
IF 1.8
Guo Lin,Yang Shu-Qing,Zhao Kai-Chun,Chen Xiao-Chao,Lu Yong,Liu Ye
The structures of 2,5-diaryl-1,3,4-oxadiazoles with good stability have attract great attention for development of new and safe therapeutic agents with functions in antimicrobial, anti-inflammatory, antitumor, and antiviral (for treatment of HIV infection), etc. In the present work, over the developed Pd-catalytic system with involvement of the 3-thiophenyl-benzimidazolyl-based mono-phosphine, the one-pot carbonylation-dehydration tandem reaction of aryl iodides with acylhydrazines for synthesis of 2,5-diaryl-1,3,4-oxadiazoles was reported for the first time with advantages of simplified manipulations, high efficiency (yields of 62–93%), as well as high safety of applied organic substrates. The relatively high reaction temperature of 140–160 ℃ was required for this tandem reaction, wherein the good stability of the involved phosphine with suitable stereo-electronic property guaranteed the fulfilment of this sequence. It was demonstrated that the first-step carbonylation of aryl iodides with acylhydrazine toward N , N′- diarylhydrazides was the rate-determine step in the overall process. Subsequently, the formed N , N' -dibenzoylhydrazides irreversible dehydrated into 2,5-diaryl-1,3,4-oxadiazoles with the presence of dehydrating agent like DCC. Graphical abstract
研究领域:
有机化学
·
药物化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Ding Wang,Jialin Yang,Liping Bao,Yu Cheng,Liang Tian,Qingxiang Ma,Jingcheng Xu,Hui-Jun Li,Xianying Wang
Hydrogen (H 2 ) molecules are easy to leak during production, storage, transportation and usage. Because of their flammability and explosive nature, quick and reliable dectection of H 2 molecule is of great significance. Herein, an excellent H 2 gas sensor has been realized based on Pd nanocrystal sensitized two-dimensional (2D) porous TiO 2 (Pd/TiO 2 ). The formation of 2D porous TiO 2 with the removal of graphene oxide template has been monitored by an in-situ transmission electron microscope. It is found that the size of the GO template can be almost completely replicated by 2D TiO 2 . The Pd/TiO 2 sensor exhibited an instantaneous response and a satisfactory low detection limit for H 2 detection. These excellent gas-sensing performances (good selectivity, unique linearity response and high stability) can be attributed to the unique 2D porous structure and the synergistic effect between oxidized Pd and TiO 2 , including the unique adsorption properties of O 2 or/and H 2 on Pd/TiO 2 , the reaction between PdO and H 2 gas, and the regulated depletion layer arising from p-type PdO to n -type TiO 2 . This work demonstrates a rational design and synthesis of highly efficient H 2 sensitive materials for energy and manufacturing security.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）