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449 results on '"Zhao, Qinfu"'

2. Enhancing carrier transfer properties of Na-rich anti-perovskites, Na4OM2 with tetrahedral anion groups: an evaluation through first-principles computational analysis

Author

Xu, Shenglin, Zhao, Qinfu, Zhang, Ronglan, Suo, Bingbing, and Song, Qi

Subjects
Condensed Matter - Materials Science
Abstract

The practical application of Na-based solid-state electrolytes (SSEs) is limited by their low level of conduction. To evaluate the impact of tetrahedral anion groups on carrier migration, we designed a set of anti-perovskite SSEs theoretically based on the previously reported Na4OBr2, including Na4O(BH4)2, Na4O(BF4)2, and Na4O(AlH4)2. It is essential to note that the excessive radius of anionic groups inevitably leads to lattice distortion, resulting in asymmetric migration paths and a limited improvement in carrier migration rate. Na4O(AlH4)2 provides a clear example of where Na migrates in two distinct environments. In addition, due to different spatial charge distributions, the interaction strength between anionic groups and Na is different. Strong interactions can cause carriers to appear on a swing, leading to a decrease in conductivity. The low conductivity of Na4O(BF4)2 is a typical example. This study demonstrates that Na4O(BH4)2 exhibits remarkable mechanical and dynamic stability and shows ionic conductivity, two orders of magnitude higher than that of Na4OBr2. This is attributed to the expansion of the carrier migration channels by the anion groups, the moderate interaction between carriers and anionic groups, and the paddle-wheel effect generated by the anion groups, indicating that the paddle-wheel effect is still effective in low-dimensional anti-perovskite structures, in which atoms are arranged asymmetrically.

Published
2023

3. Coordination Engineering in Zirconium-Nitrogen-Functionalized Materials for N2 Reduction: A First-Principles Simulation

Author

Guo, Jianpeng, Luo, Hao, Zhao, Qinfu, Suo, Bingbing, Zhou, Bo, Zhu, Haiyan, Zhang, Zhiyong, and Song, Qi

Subjects
Condensed Matter - Materials Science
Abstract

Coordination engineering was employed to optimize the coordination environment of the Zr atom anchored on the porphyrins (PP). Five promising ZrPP-A candidates as electrocatalysts for nitrogen reduction reaction (NRR) were identified through a four-step screening strategy. First-principles calculations were utilized to evaluate the performance of the candidate electrocatalysts for NRR. A comprehensive search for reaction pathways revealed that NRR reactions with these selected catalysts tend to follow a hybrid pathway. It is found that orbital hybridization and charge transfer between Zr and its coordination atoms, as well as between ZrPP-A and the adsorbed N2 ensured the stability and high catalytic activity of these selected ZrPP-A. Zr plays a crucial role in coordinating charge transfer during the NRR process. Simultaneously, the coordinating atoms and the PP moiety jointly provide additional charge transfers to or from the adsorbate. An asymmetric coordination environment results in an asymmetric charge distribution of the substrate, causing the adsorbed polarized N2 molecule oriented toward the asymmetric charge aggregation region. Our work underscores the importance of considering not only the single-atom catalyst itself but also its coordination environment for the rational design of efficient catalysts.

Published
2023

40. Investigation of electrical conductivity and oxygen relaxation behavior for BaBi0.98Sr0.02Nb5-xTixO15-δ ceramics.

Author

Zou, Qirui, Hu, Xinyu, Cao, Shuyao, Wang, Weiguo, Li, Xianyu, Zhao, Qinfu, Kang, Fang, Zhang, Ping, Chen, Lei, Wang, Dan, and Hao, Gangling

Abstract

BaBiNb5O15- based oxide ion conductors have shown promise for solid fuel cell applications at medium temperatures. In this study, BaBi0.98Sr0.02Nb5-xTixO15-δ (x = 0.02, 0.04, 0.05, 0.06, 0.08) samples were prepared by the conventional solid-state synthesis with two-step sintering method. The electrical properties and oxygen relaxation behaviors of the BaBi0.98Sr0.02Nb5-xTixO15-δ samples were investigated. With increasing the Ti content, the bulk conductivity of the BaBi0.98Sr0.02Nb5-xTixO15-δ samples showed a trend of increasing first and then decreasing. When the doped Ti content reached 5 mol%, the highest bulk conductivity of BaBi0.98Sr0.02Nb5-xTixO15-δ samples can be got, 5.27 × 10−5 S/cm at 773 K. According to the dielectric relaxation spectroscopy measurement, the BaBi0.98Sr0.02Nb4.95Ti0.05O15-δ sample exhibits the higher moveable oxygen vacancy concentration and mobility of oxygen vacancies. This could be the possible reason that there is the highest bulk conductivity in the BaBi0.98Sr0.02Nb4.95Ti0.05O15-δ sample. Additionally, the influence of sintering temperature on the electrical properties of the BaBi0.98Sr0.02Nb4.95Ti0.05O15-δ compound was investigated. When the BaBi0.98Sr0.02Nb4.95Ti0.05O15-δ sample is sintered at a temperature of 1423 K, it exhibits the best bulk conductivity and total conductivity. [ABSTRACT FROM AUTHOR]

Published
2024
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41. Depolymerizable Enzymatic Cascade Nanoreactor for Self‐Enhancing Targeting Synergistic Tumor Therapy.

Author

Song, Luming, Zhao, Qinfu, Feng, Shuaipeng, He, Ye, Li, Yian, Wang, Siling, and Zhang, Jinghai

Subjects
*VASCULAR endothelial cells, *CELL receptors, *GLUCOSE oxidase, *REACTIVE oxygen species, *METASTASIS
Abstract

Traditional targeting strategies require nanoparticles (NPs) to penetrate the vascular wall to bind tumor cell surface receptors, resulting in a small proportion of drugs that achieve targeting delivery. Based on this, a novel design of self‐enhancing targeting to tumor vascular sites has been proposed and needs to meet two preconditions: 1) It can efficiently bind to P‐selectin overexpressed by activated tumor vascular endothelial cells. 2) It can release reactive oxygen species (ROS) to the tumor site and activate resting vascular endothelial cells, thus providing more targets for subsequent preparations. Besides, to overcome the limited penetration of the tumor site, a variable‐size system needs to be designed. Red light carbon dots nanozyme (Fe(III)‐CDs) and glucose oxidase (GOx) are combined to form the enzymatic cascade nanoreactor FG. As a natural ligand of P‐selectin, fucoidan (Fu) is coated on the surface of L‐arginine‐composite FG to obtain FGA@Fu. It is demonstrated that FGA@Fu can realize weak acid/photothermal responsive depolymerization to enhance the penetration to tumors with controlled ROS release. Inspiringly, FGA@Fu can achieve “targeting‐activation‐(self‐enhanced targeting)” to tumor vasculature with good fluorescence tracking. In vivo anti‐tumor experiments showed that FGA@Fu has excellent cascade enzyme catalysis/gas/photothermal combination therapy effect and strong inhibition of tumor metastasis. [ABSTRACT FROM AUTHOR]

Published
2024
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50. Enhancing carrier transfer properties of Na-rich anti-perovskites, Na4OM2 with tetrahedral anion groups: an evaluation through first-principles computational analysis.

Author

Xu, Shenglin, Zhao, Qinfu, Zhang, Ronglan, Suo, Bingbing, and Song, Qi

Abstract

The practical application of Na-based solid-state electrolytes (SSEs) is limited by their low level of conduction. To evaluate the impact of tetrahedral anion groups on carrier migration, we designed a set of anti-perovskite SSEs theoretically based on the previously reported Na4OBr2, including Na4O(BH4)2, Na4O(BF4)2, and Na4O(AlH4)2. It is essential to note that the excessive radius of anionic groups inevitably leads to lattice distortion, resulting in asymmetric migration paths and a limited improvement in carrier migration rate. Na4O(AlH4)2 provides a clear example of where Na+ migrates in two distinct environments. In addition, due to different spatial charge distributions, the interaction strength between anionic groups and Na+ is different. Strong interactions can cause carriers to appear on a swing, leading to a decrease in conductivity. The low conductivity of Na4O(BF4)2 is a typical example. This study demonstrates that Na4O(BH4)2 exhibits remarkable mechanical and dynamic stability and shows ionic conductivity of 1.09 × 10−4 S cm−1, two orders of magnitude higher than that of Na4OBr2. This is attributed to the expansion of the carrier migration channels by the anion groups, the moderate interaction between carriers and anionic groups, and the "paddle-wheel" effect generated by the anion groups, indicating that the "paddle-wheel" effect is still effective in low-dimensional anti-perovskite structures, in which atoms are arranged asymmetrically. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
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