JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
·
2018
·
IF 3.046
Ting Wang,Qing Ma,S.-H. Song
Pure and Ba-Zr co-doped multiferroic BiFeO 3 nanopowders are synthesized via sol-gel method. X-ray diffraction demonstrates the transformation of crystal structure (from R3c to R3c + P4mm) and the absence of impurity phase. Scanning electron microscopy and transmission electron microscopy indicate that the co-doping leads to a decrease in particle size and the Bi 0.85 Ba 0.15 Fe 0.95 Zr 0.05 sample has a particle size of 30–60 nm. Surprisingly, the room-temperature magnetization hysteresis loops change to be soft ferromagnetic with co-doping. The maximum and remnant magnetizations of the as-prepared nanopowders first increase and then decrease with increasing dopant concentration with the Bi 0.85 Ba 0.15 Fe 0.95 Zr 0.05 sample having the best magnetic properties. The enhanced magnetization is due to the crystal lattice distortion caused by the ionic-radius difference between the substituent and host elements and the suppression of the antiferromagnetic spiral spin structure induced by the size effect of the nanopowders.
研究领域:
材料科学
·
纳米科技
·
多铁性材料
·
固态化学
·
磁学
✓ 已验证
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2024
·
IF 6.3
Junchi Wang,Hui Li,Ndzondelelo Bingwa,Hao Yu,Guoning Li,Qiangqiang Xiao,Shijie Li,Min Guo,Xiaoling Ma
In this study, UiO-66(Zr) and its derivative (UiO-66-C) are employed as supports to prepare shape stabilized PCM (U/SA-X and UC /SA-X) for resolving the melting leakage and poor thermal conductivity of stearic acid (SA). Thermal storage performance, including phase change enthalpy, supercooling degree, phase change temperature, thermal conductivity, and shape stability of U/SA-X and UC/SA-X, are compared. Preliminary characterization reveals that the physicochemical property evolution of the support impacts the thermal storage performance of SA . UiO-66 with microporous structure is unfavorable to enhance the shape stability of SA. U/SA-X exhibits low thermal storage efficiency and high supercooling degree owing to nanoconfinement and hydrogen bonding. By contrast, UiO-66-C possesses mesopores and graphitic structure that allows for a remarkable thermal storage performance of UC/SA-X. In detail, UC/SA-50 exhibits an ideal thermal storage performance, where the thermal conductivity (0.531 W/(m·K)) increases by 141 % in comparison to SA with a high phase change enthalpy of 93.6 J/g and low supercooling degree of 0.24 °C. It also shows satisfying thermal reliability that the thermal property of UC/SA-50 maintains stability even after 100 thermal cycles. In addition, the photothermal conversion efficiency of UC/SA-50 is up to 83.06 %.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2024
·Vol. 192
·期 1
·1-11
·
IF 5.3
Tian Siyu,Wang Jiahui,Jie Yu,Ding Zhu,Wang Xiao,Wang Jijiang,Hou Xiangyang
A novel nanobiosensor was constructed by in situ locating nanometer MnO 2 particles with controllable size and morphology in a Zr-MOF substrate to serve as an electrochemical probe. The synergistic effect of the two components, Zr-MOFs with high specific surface area and compatibility as a carrier for MnO 2 , resulted in improved electrochemical activity and excellent electrochemical identification performance for the MnO 2 @Zr-MOF/GCE biosensor. Under optimized experimental conditions and using CV and DPV technology, the biosensor showed a wide linear detection range (2–200 μM), a low detection limit (2.577 × 10 −8 M), a recovery range (106.26–115.01%), and maximum relative standard deviation (5.155) for tetracycline (TC) identification. The recognition mechanism of the sensor was investigated adopting Laviron adsorption theory. The applicability of the sensor was verified through practical measurements. Overall, the MnO 2 @Zr-MOF/GCE sensor possesses the advantages of fast analysis speed, high sensitivity, high selectivity, and simple operation, making it suitable for detecting trace amounts of TC in food. Graphical abstract
研究领域:
分析化学
·
食品安全
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Jiaxin Qu,Xueqian Wang,Langlang Wang,Bowen Xu,Ping Ning,Yixing Ma,Yibing Xie,Rui Cao,Qiang Ma
A nonmetallic N-doped Zr/Ti-based catalyst was prepared to investigate the effect of N addition on catalytic performance for carbon disulfide (CS 2 ) hydrolysis. The characterization of the catalyst indicated that doped N atoms were present as interstitial N in the TiO 2 lattice, resulting in an increase in the number of basic sites of the catalyst from 1.64 to 2.37 and from 0.68 to 2.53 for weakly basic and strongly basic sites, respectively. In addition, the doping of N promoted the formation of OH groups, which were favorable for the hydrolysis of CS 2 , from water (H 2 O) adsorbed on the catalyst, thus greatly improving the performance of catalytic CS 2 hydrolysis. However, N doping reduced the amount of chemisorbed oxygen on the catalyst surface from 44.7% to 33.4%, thus decreasing the oxidation reaction of the hydrolysis product H 2 S and improving the stability of the catalyst. CS 2 hydrolysis reaction activity and catalyst lifetime were tested. The experimental results demonstrated that the catalytic CS 2 hydrolysis performance was greatly improved after N doping, and the temperature to obtain 100% conversion was reduced from 180 °C to 130 °C. Selectivity to H 2 S was greatly improved with N-doped catalysts. Furthermore, the resistance of the catalyst to sulfate was improved. Nonmetallic N-doped Zr/Ti-based catalysts offer a new strategy for blast furnace gas desulfurization.
研究领域:
催化化学
·
环境科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Chuanzhi Sun,Hao Liu,Wei Chen,Dezhan Chen,Shuohan Yu,Annai Liu,Lin Dong,Shuai Feng
A series of Sm- and/or Zr-doped MnO x -TiO 2 catalysts were prepared, and the catalysts exhibited better N 2 selectivity and SO 2 resistance than the undoped MnO x -TiO 2 catalyst for the selective catalytic reduction of NO by NH 3 (NH 3 -SCR). The reasons for the good N 2 selectivity and SO 2 resistance of the catalysts were proposed. X-ray photoelectron spectroscopy (XPS) combined with density functional theory (DFT) calculations suggested that electron transfer between the manganese and samarium species by Mn 4+ + Sm 2+ ↔ Mn 3+ + Sm 3+ redox cycles occurred in the Sm-containing catalysts. Furthermore, electron transfer from Sm 2+ to Mn 4+ suppressed electron transfer from NH 3 to Mn 4+ , inhibiting the formation of NH 2 or NH. Thus, the pathway for NH generation was removed, and the reaction of 2NH + 4NO → 3N 2 O + H 2 O was prevented. Consequently, the N 2 selectivity of the NH 3 -SCR reaction was enhanced. In situ diffused reflectance infrared Fourier transform spectroscopy ( in situ DRIFTS) combined with thermogravimetry, differential scanning calorimetry and mass spectrometry (TG-DSC-MS) results revealed that the deposition rate of sulfate species decreases after Sm doping, which was also attributed to the suppressed electron transfer from SO 2 to Mn 4+ , i.e., the oxidation of SO 2 to SO 3 . Thus, the catalysts exhibited better SO 2 resistance.
研究领域:
催化化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2016
·
IF 3.15
Chengxin Fu,Yinyan Gong,Yitao Wu,Jiaqi Liu,Zhen Zhang,Can Li,Lengyuan Niu
Visible-light photodegradation test revealed that B and Zr co-doping can raise the photocatalytic ability of the undoped TiO 2 by a fold. XRD crystallography and Raman phonon spectroscopy measurements suggest that the Zr 4+ ions replace the Ti 4+ ions while the B 3+ ions occupy the interstitial sites, expanding the unit-cell volume and reducing crystallite size. The incorporation of interstitial boron dopants creates oxygen vacancies (Ov ) and reduce Ti 4+ to Ti 3+ to form [Ov -Ti 3+ ] + , which traps the carriers and prolongs carrier lifetime. Moreover, Zr 4+ ions replace Ti 4+ ions and form impurity levels, which could improve visible light response. The co-doped samples are benefited from both B interstitials and Zr substitutes.
研究领域:
材料科学
·
化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2024
·Vol. 14
·期 30
·21799-21807
·
IF 3.9
Yijin Sheng,Fangxu Hu,Yu Wu,De Li,Wenting Ji,Yong Chen
The electrochemical oscillation in Li-ion batteries has been reported for two-phase electrode materials of Li4Ti5O12 and LiCrTiO4, which is originated from the group-by-group phase transition in a multi-particle electrode. For both Li4Ti5O12 and LiCrTiO4, the electrochemical oscillation exhibits usually during charging, while rarely for discharging. Herein, a series of Zr-modified Li4Ti5O12 samples are prepared by using the spray-drying combined with high-temperature sintering method, and the electrochemical oscillation is observed during not only the charging process, but also the discharging process, which gradually grows up and then disappears by increasing the Li content. Compared with Li4Ti5O12, the specific capacity of Zr-modified Li4Ti5O12 decreases gradually by increasing the Zr/Ti ratio, owing to the impurity phases. According to the XRD, XPS and STEM results, the Zr element tends to accumulate on the surface to form ZrO2 nanoparticles, rather than dope into the bulk phase of Li4Ti5O12, which makes Li4Ti5O12 particles well dispersive. In contrast to the Li deficiency for only charging, the electrochemical oscillation during both charging and discharging should be attributed to the Li excess, but too much Li2TiO3 phase will suppress the electrochemical oscillation. Therefore, the Li excess can induce the electrochemical oscillation during both charging and discharging of Zr-modified Li4Ti5O12, which can be adopted to investigate the electrochemical oscillation of other materials in LIBs.
研究领域:
材料科学
·
电化学
·
电池技术
·
纳米技术
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Yun Fan,Haijun Zhang,Meihui Ren,Yichi Zhang,Yun Li,Longxing Wang,Jiping Chen
It is of great significance to develop the low-temperature catalysts for the reduction in emission of chlorinated aromatic hydrocarbons (CAHs) from the industrial thermal processes. In this work, the bimetallic Ce-Zr/UiO-66 catalysts were synthesized by a solvothermal method to degrade CAHs. Powder X-ray diffraction, Fourier transform infrared spectra and X-ray photoelectron spectroscopy analyses showed that cerium was successfully incorporated into the lattice of Zr/UiO-66 without destroying the structure of metal–organic frameworks. The activities of Ce-Zr/UiO-66 catalysts for CAHs degradation varied with the concentration of cerium. Ce 0.2 Zr 0.8 /UiO-66 with the highest surface area (1502 m 2 g −1 ) presented the highest efficiency (>85%) for hexachlorobenzene degradation at low heating temperature (100–150 °C) with less formation of polychlorinated dibenzo- p -dioxins and dibenzofurans. Appropriate amount of water (5 wt%) and nitrogen atmosphere were beneficial to improve degradation efficiency. The degradation products proved that hydrodechlorination and oxidation of CAHs both occurred on the catalysts.
研究领域:
环境化学
·
催化
·
材料科学
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2023
·Vol. 13
·期 20
·5902-5911
·
IF 5
Haoxi Jiang,Liping Yi,Guochao Yang,Lingtao Wang
Hierarchical Zr-β zeolite is a promising catalyst in the conversion of ethanol to 1,3-butadiene owing to the improved accessibility of active sites inside the zeolite to bulky substrates. Accordingly, hierarchical nanocrystalline Zr-β zeolite with sufficient intercrystalline mesoporosity and microporosity was prepared in this work via silanization-based hydrothermal synthesis. A systematic investigation was conducted to determine the effect of the secondary porosity on the textural, acidic and catalytic properties. The results suggested that neither acid amount, strength nor location varied with the additional secondary porosity. However, an appropriate proportion of micropores and mesopores would provide significant contributions to enhanced catalytic performance, arising from the available confined environment around the active sites inside the micropores, enhanced accessibility of such sites and improved diffusion of reactants and products due to mesopores.
研究领域:
化学工程
·
催化
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2024
·
IF 4
Tianyu Wang,Wenyan Guo,Yonghui Xia,Yuefang Zhu,Li Chen,Yafeng Zhang,Guangli Li
The abuse and persistent use of Lomefloxacin (LOM) produces residues that deteriorate the ecological environment and endanger human health. Therefore, it is highly urgent to establish a simple and reliable method for the determination of LOM to guarantee food safety. Herein, a sensitive voltametric sensor based on bimetallic UiO-66(Zr/Ce) MOF/reduced graphene oxide (UiO-66 (Zr/Ce)/rGO) was fabricated for the determination of trace LOM residues in milk. The UiO-66(Zr/Ce)/rGO increased the electroactive surface area and lowered the charge transfer resistance. Due to the synergistic interactions between UiO-66(Zr/Ce) MOFs with good electrocatalytic activity and rGO nanosheets with high electrical conductivity, the UiO-66(Zr/Ce)/rGO/GCE exhibited the highest peak current response of LOM, 4.2-fold higher than the bare GCE. Consequently, the UiO-66(Zr/Ce)/rGO showed remarkably electrocatalytic activity for LOM oxidation with two broad linear detection ranges (0.03 – 2.0 μM and 2.0 – 30 μM), high sensitivities (5.1254 and 0.2198 μM μA −1 ), and a low detection limit (5.0 nM). The UiO-66(Zr/Ce)/rGO exhibited strong anti-interfering ability against potential interfering species even at high concentration, and maintained robust voltametric responses up to 25 days. Moreover, the UiO-66(Zr/Ce)/rGO/GCE achieved accurate determination of trace LOM residues in liquid milk with good recovery (96.11 − 103.2 %) and highly consistent sensitivity with that in PBS.
研究领域:
分析化学
·
食品安全
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Chao Zhang,Yongsheng Gao,Haipeng Wang,Lulu Jiang,Delu Zhang,Shujun Ming,Guangying Fu,Chao Wang,Zhiguo Lv
The dry reforming of methane (DRM) could convert CH 4 and CO 2 into syngas, offering potential for greenhouse gas mitigation. However, DRM catalyst sintering and carbon deposition remain major obstacles. In this study, a highly dispersed PtNi alloy@Zr-doped 3D hollow flower-like MgAl 2 O 4 (AMO) spheres was prepared through a hydrophobic driving strategy. During a 50-hour test at 550 °C, the catalyst exhibited no significant decline in CH 4 and CO 2 conversion rates, demonstrating its excellent anti-sintering and anti-coking performance. The unique anti-coking performance can be attributed to Zr-induced oxygen vacancies, which enhance oxygen mobility and reduce carbon deposition. Besides, doped Zr increases basic active sites, enhancing CO 2 adsorption and activation, thus accelerating carbon species conversion. At 700 °C, the unique synergy between highly dispersed Pt and Ni enabled CH 4 and CO 2 conversion rates to reach 67.5 % and 73.8 %, respectively. The incorporation of Pt or Zr extends the Ni–Ni bond and partially coordinates with Ni, enhancing the stability of the Ni lattice. The reaction of CH 4 and CO 2 follows the Langmuir-Hinshelwood (L-H) mechanism, where both reactant molecules are adsorbed and activated on the metallic sites. Moreover, the effective energy barrier for the CH oxidation pathway is lower by 0.16 eV than that for the C oxidation pathway, which helps suppress the formation of carbon deposits.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Peng Hu,Xiaopeng Liang,Muhammad Yaseen,Xiaodan Sun,Zhangfa Tong,Zhongxing Zhao,Zhenxia Zhao
A novel mechano-chemical strategy using dopamine to modify UiO-66(Zr) by N-coordination was proposed to enhance its competitive adsorption for acetaldehyde, chlorobenzene/H 2 O, both thermodynamically and kinetically. The newly synthesized material was characterized by SEM, EDX, XPS, PXRD, FT-IR, TGA/DTG and BET techniques. Results showed that N was successfully grafted into UiO-66(Zr) frameworks through coordination interaction with Zr-O clusters resulting in M-UiO-66(Zr-N 3.0 ). The obtained M-UiO-66(Zr-N 3.0 ) exhibited a significant increase in adsorption of chlorobenzene (4.94 mmol/g) and acetaldehyde (9.42 mmol/g) compared to parent UiO-66(Zr) and UiO-66(Zr)-NH 2 . The H 2 O adsorption uptake of M-UiO-66(Zr-N 3.0 ) decreased by 20% that of UiO-66(Zr) and 47% of UiO-66(Zr)-NH 2 indicating higher hydrophobicity of the modified material. Kinetic performance indicated that diffusivity of chlorobenzene on M-UiO-66(Zr-N 3.0 ) was about 7.8 and 40 times higher than that of the parent UiO-66(Zr) and UiO-66(Zr)-NH 2 respectively and 15.4 times higher than that of H 2 O on itself. Based on the results, the current N-modification strategy can be deemed as an efficient way to improve MOFs competitive adsorption towards VOCs under humid conditions and it might play active role in industries involving adsorbent applications.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子