Catalysis Science & Technology
·
2017
·Vol. 7
·期 3
·725-733
·
IF 5.773
Ning Liu,Zhimin Wu,Meng Li,Shanshan Li,Yongfei Li,Rongdong Yu,Langsheng Pan,Yuejin Liu
Bimetallic Al–La oxides were conjointly precoated on SBA-15 prior to the introduction of potassium fluoride to achieve solid superbases at low temperature by a modified wetness impregnation method. This breaks the tradition of decomposition of KNO3 at high temperature and gives rise to a new approach to generating superbasic sites on SBA-15. The physico-chemical characteristics of the prepared KF/Al–La@SBA-15 materials were investigated using FT-IR, XRD, TG-DTG, N2 adsorption–desorption, TEM, SEM-EDS, acid–base titration, Hammett indicators and CO2-TPD measurements. The results demonstrated that the addition of Al species promoted the dispersion behavior of La species inside the channels, and the bimetallic species could synergistically protect the mesoporous structures of SBA-15 against KF corrosion. With increasing Al content, KF/Al–La@SBA-15 exhibited a long-range ordering of the pores with relatively narrow pore size distribution as well as high specific surface area. The research results showed that the KF/Al–La@SBA-15 (0.4) catalyst possessed a total basicity up to 0.79 mmol g−1 and superbasicity with a strength of 26.5. The catalytic activity of the prepared materials was evaluated in the ring-opening reaction of propylene oxide with methanol. Compared with the SBA-15 supported monometallic oxide (Al or La) catalysts, KF/Al–La@SBA-15 (0.4) exhibited the highest catalytic activity for the ring-opening reaction of propylene oxide with methanol. This is associated with the synergistic effects between Al and La species and the high dispersion of active components on the SBA-15 support.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2023
·
IF 6.6
Liyu Chen,Jiaxin Yang,Yifan Zhang,Shaohua Wu,Youjian Yang,Wenju Tao,Jiangyu Yu,Zhaowen Wang
The electrochemical behavior of Zr(IV) on a molybdenum (Mo) electrode in a KF-AlF 3 -Al 2 O 3 -ZrO 2 molten salt system was studied using cyclic voltammetry (CV), square-wave voltammetry (SWV) and chronopotentiometry (CP). The reduction process of Zr(IV) was found to follow a two-step, two-electron transfer mechanism: Zr(IV)+2e − →Zr(II) and Zr(II)+2e − →Zr(0). The reduction process was quasi-reversible and controlled by diffusion. Al-Zr alloys were successfully obtained on Mo and liquid aluminum electrodes by potentiostatic electrodeposition . Flower-like AlZr 3 and irregular granular Al 3 Zr were obtained on the Mo electrode, which were mainly attributed to the electrochemical co-reduction of Al(III) and Zr(IV) in the molten salt. Three Al-Zr alloy phases, Al 3 Zr , Al 3 Zr 2, and Al 2 Zr, were obtained on the liquid aluminum electrode, among which Al 3 Zr was dominant in the product, followed by Al 3 Zr 2 .
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2021
·Vol. 12
·期 1
·1-11
·
IF 14.919
Qin Chichu,Wang Dong,Liu Yumin,Yang Pengkun,Xie Tian,Huang Lu,Zou Haiyan,Li Guanwu,Wu Yingpeng
Potassium (K) metal is a promising alkali metal anode for its high abundance. However, dendrite on K anode is a serious problem which is even worse than Li. Artificial SEI (ASEI) is one of effective routes for suppressing dendrite. However, there are still some issues of the ASEI made by the traditional methods, e.g. weak adhesion, insufficient/uneven reaction, which deeply affects the ionic diffusion kinetics and the effect of inhibiting dendrites. Herein, through a unique self-catalysis tribo-electrochemistry reaction, a continuous and compact protective layer is successfully constructed on K metal anode in seconds. Such a continuous and compact protective layer can not only improve the K + diffusion kinetics, but also strongly suppress K dendrite formation by its hard mechanical properties derived from rigid carbon system, as well as the improved K + conductivity and lowered electronic conductivity from the amorphous KF. As a result, the potassium symmetric cells exhibit stable cycles last more than 1000 h, which is almost 500 times that of pristine K.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·
IF 2.7
Wei Liu,Shilong Cai,Hefeng Zhang,Yifu Huang
The presence of well-conductive polydimethylsiloxane (PDMS)-based ionogel has changed the stereotype of PDMS of being an insulator, owing to continuous ionic liquid (IL) phase with superior ionic conductivity. However, the sacrifice on the transparency of ionogel often occurs if increasing IL content, and to overcome the immiscibility between nonpolar PDMS and polar IL is still regarded as a considerable challenge today. Herein a new strategy to prepare a transparent, highly conductive PDMS-based ionogel with high IL content is proposed, using a “composite” surfactant of KF-6017 and LiTFSI. Benefited from unique microphase separation during gel formation, the optimal ionogel of IG 70%–1%–1% can possess excellent transparency (>95%, ~200 μm) with IL content of 70%, while owning ionic conductivity of 3.28 mS/cm and tensile property of 100 kPa. A new mechanism on the conductivity of ionogel is proposed by the molecular simulation. The ionogel can be suitable for applying as electrolyte (B) and a polymer binder for active carbon powders (as electrode A). As a result, the assembled electrochemical double-layer capacitor (A/B/A) can be flexible accompanied with excellent electrochemical performance, which exhibits a promising future for flexible electronics and wearable devices.
研究领域:
材料科学
·
化学工程
·
柔性电子学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NUCLEAR MATERIALS
·
2026
·
IF 3.3
Wenjun Liang,Xiaoli Li,Tao Wu,Jichao Bu,Yumiao Wang,Li Guo,Bin Leng,Litao Chang
The combined effects of high-temperature creep and molten salt corrosion present critical challenges for structural materials in molten salt reactors (MSRs). In the present study, the influence of surface preparation on the crack initiation behavior of Ni-based alloy GH3535 under simultaneous creep deformation and molten salt corrosion was investigated. Specimens with three different surface conditions were prepared and tested in molten LiF–NaF–KF salt at 700 °C under identical constant stress. The post-test specimens were then examined using multi-scale techniques. The results show that extensive intergranular cracking occurred in the as-machined specimen. Removing the machined layer by grinding and polishing produced specimens with relatively uniform microstructure, which suppressed subsurface crack nucleation but promoted the initiation of shallow intergranular cracks from the surface. In the high temperature annealed specimen, the machined layer was eliminated due to recrystallization. The annealing process suppressed subsurface creep crack initiation but promoted localized intergranular corrosion, leading to the detachment of recrystallized grains from the surface and subsequent surface driven cracking. These findings demonstrate that the near surface microstructure critically governs the synergy between corrosion and crack initiation of the alloy GH3535 in molten salt. While removing the machining induced zone avoids subsurface cracking, it may increase the susceptibility to intergranular corrosion and surface crack initiation, thereby providing essential guidance for surface state optimization strategies for materials in MSR applications.
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2018
·
IF 3.235
Ming Li,Xiaoli Xi,Qingqing Liu,Zuoren Nie,Liwen Ma
In this study, WC–10Co cemented carbide scrap was used as a consumable anode to separate and prepare tungsten and cobalt powders in NaF–KF melts at 1073 K. The feasibility of direct electrochemical dissolution of WC main phase to produce metallic tungsten was analyzed by thermodynamic calculations and experimental verifications. Furthermore, a series of electrolysis experiments were performed under constant cell voltage for selective preparation of tungsten and cobalt powders. The results show that metal cobalt powder was obtained at ≤0.6 V whereas metal tungsten powder was produced between 0.6 V and 1.2 V. The analysis of cathode products using scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) show that tungsten and cobalt powders can be prepared in NaF–KF melts. Finally, linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) were used to investigate the dissolution of WC–10Co anode. The electrochemical properties of tungsten and cobalt ions in NaF–KF melts were studied by cyclic voltammetry (CV) and square wave voltammetry (SWV). The results show that WC–10Co anode could be used to produce tungsten and cobalt powders and the electroreduction of tungsten and cobalt ions in NaF–KF melts was achieved through a one-step reaction involving the transfer of two electrons.
✓ 已验证
DOI
高影响因子
ACS Omega
·
2024
·
IF 3.7
Qiang Mei,Baiwen Gu,Yinyu Jiang,Yulin Wang,Weiju Lai,Hu Chen,Jide Chen,Xianxian Zhao
Signal amplification strategies have emerged as a prominent tool in the field of improving the detection sensitivity of small extracellular vesicles (sEVs). It is important to highlight that the utilization of signal quenching strategies is not commonly implemented. A detection technique for sEVs was established based on the unwinding of G-quadruplex using Klenow fragment polymerase (KF), which served as an inspiration for this study. This system is characterized by its simplicity and lack of labeling, making it an efficient approach for signal quenching. In the presence of sEVs, the CD63 aptamer in the capture@sMBs complex binds with the CD63 protein on the surface of sEVs to release trigger sequences, which were employed as a primer to mediate the DNA polymerase/endonuclease-assisted signal recycling. The signal recycling process produces numerous single-stranded DNA sequences that can bind to the toehold section of the G-quadruplex. This leads to the rupture of the G-quadruplex structure and the subsequent deactivation of a DNAzyme generated by the G-quadruplex structure and hemin, thereby inhibiting its biological catalytic function. Consequently, the G-quadruplex structure would undergo a transformation to a duplex structure, leading to the emergence of a discernible differential signal that can be noticed in a majority of instances, even without the aid of magnification devices. The decrease in the prominent signal allows for the efficient analysis of target sEVs, which exhibit a notably low detection limit. In addition to the detection of sEVs, the approach has also been utilized for the investigation of miRNA-21. The approach demonstrates a high level of selectivity and robustness in its capacity to differentiate between target miRNA and base-mismatched miRNA as well as other miRNA families. This statement suggests that the assay holds significant promise for use in biochemical research and clinical diagnosis.
研究领域:
生物化学
·
分子生物学
·
临床诊断
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）