RSC Advances
·
2021
·Vol. 11
·期 16
·9450-9458
·
IF 3.361
Rui Zhang,Zheng Wang,Lin Zhu,Weixin Lv,Wei Wang
For the electrochemical reduction of oxygen the development of heteroatom-doped carbon-based transition metal catalysts has become a recognized strategy to replace traditional noble metal catalysts. In this work a catalyst consisting of CoFe nanoparticles encapsulated in N-doped carbon-based materials (NC) supported by carbon nanotubes (CNTs), i.e. Fe3Co1@NC/CNTs, was modified via treatment with a phosphate salt to synthesize a P-Fe3Co1@NC/CNTs catalyst. The P-Fe3Co1@NC/CNTs exhibits with 5.29 mA cm−2 an enhanced current density which is comparable to a Pt/C catalyst. In addition, a stability and methanol resistance better than the Pt/C catalyst were observed which is ascribed to the carbon encapsulation and the synergies between the two transition metals. Finally, the reaction mechanism of P-doping was studied and discussed. These results provide possible directions for carbon-based catalysts and doping with heteroatoms for the improvement of catalytic activity. Moreover, the zinc–air battery assembled with P-Fe3Co1@NC/CNTs as the air-cathode exhibited a high-power density of 73 mW cm−2, which is comparable to that of Pt/C (71 mW cm−2) and a specific capacity of 763 mA h g−1. The prepared catalyst could potentially serve to take the place of precious metal catalysts in rechargeable Zn–air batteries.
研究领域:
电催化
·
材料化学
·
能源化学
·
纳米材料
·
电化学能源存储
·
燃料电池
·
金属-空气电池
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2022
·Vol. 43
·期 9
·2443-2452
·
IF 12.92
Yaojia Cheng,Haoqiang Song,Jingkun Yu,Jiangwei Chang,Geoffrey I.N. Waterhouse,Zhiyong Tang,Bai Yang,Siyu Lu
The sluggish kinetics of oxygen reduction reaction (ORR) hinders the commercialization of Zn-air batteries (ZABs). Manipulating the electronic structure of electrocatalysts to optimize the adsorption energy of oxygen-containing intermediates during the 4e − ORR offers a practical route toward improving ORR kinetics. Herein, we designed a novel ORR electrocatalyst containing Co single atoms and nanoparticles supported by carbon dots-derived carbon nanoflowers (Co SAs/NPs CNF). Co SAs/NPs CNF possessed a very high ORR activity ( E 1/2 of the Co SAs/NPs CNF catalyst is 0.83 V ( vs. RHE)), and outstanding catalytic performance and stability when used as the air-electrode catalyst in rechargeable ZABs (152.32 mW cm −2 , 1000.58 mWh g Zn −1 , and over 1300 cycles at a current density of 5 mA cm −2 ). The Co SAs and Co NPs cooperated to improve electron and proton transfer processes during ORR. Theoretical calculations revealed that the presence of adjacent Co NPs optimized the electronic structure of the isolated Co-N 4 sites, significantly lowering the energy barriers for the rate-determining step in ORR (adsorption of *OOH) and thereby delivering outstanding ORR performance. This work reveals that the combination of supported single-atom sites and metal nanoparticles can be highly beneficial for ORR electrocatalysis , outperforming catalysts containing only Co SAs or Co NPs.
研究领域:
电化学
·
纳米材料科学
·
能源化学
·
催化化学
·
先进电池技术
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2013
·Vol. 1
·期 35
·10184-10192
·
IF 0
Jie Shao,Xuezhang Xiao,Lixin Chen,Xiulin Fan,Leyuan Han,Shouquan Li,Hongwei Ge,Qidong Wang
A system of 2LiH–MgB2 and its hydrogenated 2LiBH4–MgH2 is an attractive candidate for hydrogen storage. However, its hydriding–dehydriding kinetics have to be further improved for practical application. In the present work, three kinds of Ni–B nanoparticles with different crystalline states and particle sizes were prepared by wet-chemical reduction and mechanochemical methods, and then introduced into a 2LiH–MgB2 composite for catalytic enhancement. The catalytic roles of Ni–B nanoparticles on the hydriding–dehydriding properties were investigated systematically. The results show that all of the Ni–B nanoparticles can significantly enhance the hydriding–dehydriding kinetics of the 2LiH–MgB2 composite, resulting in no incubation period for the formation of MgB2 during dehydrogenation. The more disordered the amorphous structure and the smaller sized the Ni–B particles are, the better the catalytic effect that is obtained. Microstructure analyses clearly reveal the formation of the MgNi3B2 phase in the dehydriding process, which acts as the nucleation agent for MgB2 formation determined by an edge-to-edge model. Directly doping with Ni–B nanoparticles in the 2LiH–MgB2 system shows a higher hydrogen desorption capacity of 9.4 wt% and obtains a better catalytic efficiency than doping with NiCl2.
研究领域:
材料科学
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储能材料
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无机化学
·
纳米催化
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氢储存
✓ 已验证
DOI
Science China-Materials
·
2021
·Vol. 65
·期 3
·721-731
·
IF 8.273
Xu Hui,Jin Meng,Geng Jing,Zhang Shengbo,Zhang Haimin
The decentralized production of H 2 O 2 via a two-electron oxygen reduction reaction (2e − ORR) has emerged as a promising alternative to the energy-intensive anthraquinone (AQ) process. However, its practical application requires 2e − ORR electrocatalysts with high activity and selectivity. Herein, we report the synthesis of metallic Ni nanoparticles anchored on bacterial cellulose-derived carbon fibers (Ni-NPs/BCCF) via a facile impregnation-pyrolysis method as efficient electrocatalysts for 2e − ORR to H 2 O 2 . By tuning the amount of Ni precursor, the best electrocatalytic performance toward 2e − ORR was achieved for Ni-NPs/BCCF-20.7, affording a high H 2 O 2 selectivity of ∼90% and an onset potential of 0.75 V vs. reversible hydrogen electrode (RHE) in an alkaline electrolyte. Ni-NPs/BCCF-20.7 achieved the largest H 2 O 2 yield rate of 162.7 ± 13.7 mmol g cat −1 h −1 and the highest Faradaic efficiency of 93.9% ± 4.2% at 0.2 and 0.5 V vs. RHE from the bulk ORR system, respectively. Theoretical calculations revealed the more favorable “end-on” adsorption configuration of molecular oxygen on the exposed Ni(111) plane, which can effectively suppress the O-O bond dissociation, resulting in high selectivity for H 2 O 2 generation.
研究领域:
材料化学
·
电化学
·
纳米催化
·
能源科学
·
环境工程
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
·
2018
·
IF 2.207
Hongyu Shi,Na Li,Zhixia Sun,Tianqi Wang,Lin Xu
TiO 2 nanoparticles are commonly used as versatile precursors to make functional nanocomposite materials. However, the surface defects at grain boundaries of TiO 2 nanoparticles significantly affect the photoelectric properties of TiO 2 nanomaterials . In this work, we firstly prepared nanocomposites of TiO 2 and polyoxometalates (POMs) in which different POMs, including titanium-substituted POMs K 5 [PW 11 TiO 40 ] and K 7 [PW 10 Ti 2 O 40 ], are incorporated with TiO 2 nanoparticles so as to make an interface modification on grain boundaries of TiO 2 nanoparticles. Then the photoconductivities of the TiO 2 /POM nanocomposites were investigated through measurement of photocurrent responses, current-voltage curves, Mott-Schottky plots and surface photocurrent spectra. Compared with pure TiO 2 nanoparticles, TiO 2 /POM nanocomposites exhibit superior photoelectric properties, benefitting from the interface modification from different POMs. The gas sensing performance for acetone was also explored by use of the as-prepared photoconductive devices, and TiO 2 /PW 11 Ti exhibited a high gas sensing performance.
研究领域:
材料科学
·
纳米科技
·
半导体物理
·
传感器技术
·
光电子学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2018
·Vol. 135
·期 26
·46416
·
IF 1.901
Xiang Lin,Kai Zhang,Ke Li,Dongyun Ren
Carbonaceous nanoparticles (CNPs), including carbon black, carbon nanotubes, and graphene nanopiece, were selected as nanoadditives for investigating the rheological behavior dependence of their polymer-based composites on morphological and interfacial structure. Polypropylene (PP) was adopted as matrix and a series of contents of CNPs were used for sample compounding. With identical concentration, the morphological structure of CNPs was emphasized as the dominant effect affecting the shear viscosity and the compressibility of PP/CNPs melts. The viscosity dependence on the CNPs contents and physical structure, such as particle size, aspect ratio, and specific area, was fully discussed in this work. The newly-introduced inner voids, induced around the interface region between matrix and CNPs during physical mixing, were contributive to the rheological deviation, which was further reflected from the melt compressibility. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46416.
研究领域:
高分子科学
·
复合材料学
·
流变学
·
纳米材料科学
·
聚合物加工
✓ 已验证
DOI
高影响因子
Small
·
2018
·Vol. 14
·期 31
·1801680
·
IF 9.598
Jiangjiang Zhang,Wenshu Zheng,Xingyu Jiang
Chemical regulation of enzyme-mimic activity of nanomaterials is challenging because it requires a precise understanding of the surface chemistry and mechanism, and rationally designed applications. Herein, Ag + -gated peroxidase activity is demonstrated by successfully modulating surface chemistry of cetyltrimethylammonium bromide-capped gold nanoparticles (CTAB-AuNPs). A surface blocking effect of long-chain molecules on surfaces of AuNPs that inhibit peroxidase activity of AuNPs is found. Ag + ions can selectively bind on the surfaces of AuNPs and competitively destroy CTAB membrane forming Ag + @CTAB-AuNPs complexes to result in enhanced peroxidase activity. Ag + @CTAB-AuNPs show the highest peroxidase activity compared to similar-sized citrate-capped and ascorbic acid-capped AuNPs. Ag + @CTAB-AuNPs can potentially develop into analyte-responsive systems and exhibit advantages in the optical sensing field. For example, the Ag + @CTAB-AuNPs system shows an enhanced sensitivity and selectivity for acetylcholinesterase activity sensing compared to other methods.
研究领域:
纳米生物技术
·
分析化学
·
酶学
·
生物传感器
·
分子诊断
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转化医学
·
药物代谢
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2013
·Vol. 34
·期 12
·2161-2166
·
IF 1.304
Mingming Zhang,Manman Jiang,Changhai Liang
A basic anion exchange resin , Amberlite IRA-900, was loaded with Pd(C 3 H 5 )(C 5 H 5 ) by an easy metal-organic chemical vapor deposition (MOCVD) approach to give Pd@IRA-900 catalyst after reduction at room temperature . Ultraviolet-Visible spectroscopy results showed a red shift of the absorption peak of Pd 2+ after the Pd precursor was loaded on the resin, indicating that a chemical reaction occurred between the precursor and the support. Pd nanoparticles with 2.6 nm of average size were well dispersed on the support. The Pd@IRA-900 catalyst showed high activity for different kinds of aryl halides in Suzuki-Miyaura coupling reactions under mild and aerobic conditions. Excellent recyclability of Pd@IRA-900 catalyst was also observed in the Suzuki-Miyaura coupling reaction of iodobenzene and phenylboronic acid . A bifunctional catalyst Pd@IRA-900(OH) was synthesized by pretreating the ion exchange resin support with NaOH before Pd loading, which successfully catalyzed the Suzuki-Miyaura reaction of iodobenzene and phenylboronic acid without base under aerobic conditions.
研究领域:
催化化学
·
有机合成
·
材料化学
·
绿色化学
·
纳米催化
✓ 已验证
DOI
高影响因子
PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION
·
2018
·Vol. 36
·期 1
·1800077
·
IF 4.384
Yiqi Zhuang,Linlin Liu,Xiaoyan Wu,Yu Tian,Xuehong Zhou,Shuping Xu,Zengqi Xie,Yuguang Ma
The “far-field” surface plasmon resonance (FSPR) of metal nanoparticles, which have built a facile way to emission enhancement of red, green, blue, and white with nice reproducibility, has big potential application in solution-processed organic light-emitting diodes (OLEDs). According to the theory of the “far-field” effect, the reflectivity of the metal surface and the phase shift at the reflection play an important role in enhancing ratio, which strongly relate to the size and shape of nanoparticles. In this work, gold nanospheres with different sizes and nanorods are synthesized in order to determine the size and shape effect of FSPR. The results demonstrate that the one with higher reflectivity in a certain range induces a better emission enhancement in the luminous efficiency and the maximum brightness. The nanoparticles with bigger sizes and shape of rods have higher reflectivity, which is consistent with the simulation based on FSPR effect. The phase shifts of different nanoparticles are optimized by the distance between gold nanoparticles and emitters. The metal NPs with a high reflectivity and the applicable phase shift will have big potential for the emission enhancement in OLEDs.
研究领域:
纳米光学
·
材料科学
·
光电子学
·
表面等离子体学
·
有机光电子器件
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Hongyuan Qin,Jiawei Huang,Xueli Zhang,Ling Yu,Yang Yu
In this study, lanthanum hydroxide adsorbent was synthesized through a simple hydrothermal method and applied for removing phosphate from water. The optimal adsorbent was obtained at the La/OH molar ratio of 4:1. The adsorbent showed rapid adsorption of phosphate within the first 4 h in which approximately 84% of the equilibrium adsorption capacity can be achieved. The phosphate uptake was highly dependent on solution pH. The better fit of the Langmuir isotherm model to experimental data indicated that the monolayer adsorption occurred and the maximum adsorption capacity of 193.9 mg/g was accomplished at pH 7.0. The presence of fluoride could significantly retard the uptake of phosphate. X-ray photoelectron spectroscopy analysis indicated that hydroxyl groups on the adsorbent surface played the most key role in the adsorption. The phosphate ions were adsorbed on the adsorbent through the formation of inner-sphere complexes.
研究领域:
环境化学
·
纳米材料科学
·
水污染控制
·
表面化学
·
吸附科学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2012
·Vol. 39
·期 4
·3915-3919
·
IF 1.751
Junxia Wang,Hengchang Nie,Chunfeng Lan,Genshui Wang,Xianlin Dong,Xuefeng Chen,Fei Cao,Hongliang He
Porous Pb (Zr 0.95 Ti 0.05 ) O 3 / x MgO (PZT/MgO, x =0, 0.1, 0.2, 0.5 and 1.0 wt%) ferroelectric ceramics were prepared with MgO nanoparticles as reinforcing phase. The effects of MgO nanoparticles on the phase, microstructure, electrical and mechanical properties of as-prepared ceramics were investigated. The results show that the grain size is reduced obviously when increasing the amount of MgO. Compared with pure porous PZT, T C of MgO-added PZT ceramics shifts to higher temperature. Moreover, dielectric, ferroelectric and piezoelectric properties show no much degradation. Further, PZT/MgO ceramics possess enhanced mechanical properties compared to pure porous PZT ceramics, the largest increment of the fracture toughness and hardness being 31.3% and 19.8%, respectively. The optimal electrical and mechanical properties are obtained with the addition of less than 0.5 wt% MgO nanoparticles.
研究领域:
材料科学
·
无机非金属材料
·
功能陶瓷
·
电子材料
·
固态物理
·
纳米复合材料
✓ 已验证
DOI
高影响因子
CRYSTENGCOMM
·
2014
·Vol. 16
·期 37
·8910-8916
·
IF 3.858
Feng Ye,Hui Liu,Wenlai Huang,Jun Yang
Controlling the morphology of noble metal nanoparticles can be an effective way to produce nanomaterials with favourable properties. Herein, we report our study on the effects of diffusion rate and reaction kinetics on the morphology of a number of noble metal (Au, Ag, Pd, and Pt) nanoparticles. A glass reactor based on electrochemical reduction or photo-reduction has been designed to achieve control of diffusion and chemical reduction of the different noble metal precursors. The results show that the noble metal nanoparticles with flower-like, core–shell, or wheel-like morphologies could be obtained at a relatively high diffusion rate due to the presence of additional growth of metal precursors on the preformed metal nuclei, while at relatively low diffusion, the as-prepared noble metal nanoparticles are small and quasi-spherical due to the relatively fast reduction of metal precursors. The experimental observations are also confirmed qualitatively by kinetic Monte Carlo (kMC) simulations. Since diffusion and reaction kinetics are universal and key factors in the synthesis of nanomaterials, the findings in this work might provide an effective way to manipulate the morphology of nanomaterials for a given application.
研究领域:
纳米材料科学
·
物理化学
·
材料合成
·
胶体与界面化学
·
计算材料学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）