Journal of Energy Storage
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2024
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IF 8.9
Bin Hu,Wenxuan Hu,Xinyuan Qian,Min Zuo,Ziliang Wu,Yihu Song,Qiang Zheng,Guorong Shan,Miao Du
Layered double hydroxides (LDHs) have garnered significant attention as electrode materials for their ultra-high theoretical capacitance. However, LDHs are prone to phase transition and volume changes during charge/discharge process, which adversely affect their cyclic stability and applications. In this paper, a small amount of non-electrochemically active element, scandium (Sc), was firstly introduced into NiCo-LDHs by a facile and fast one-step potentiostatic electrodeposition with NH 4 Br as a modulator, effectively mitigating the influence of the Jahn-Teller effect. By doping slight Sc into NiCo-LDHs, the resulting electrode exhibited excellent electrochemical performance , with a specific capacitance of 1994 F g −1 (at 1 A g −1 ), and ultralong lifespan, retaining 82.7 % of its initial capacitance after 30,000 charge-discharge cycles. This work presents a promising strategy for the rapid preparation of LDHs-based supercapacitor electrodes that deliver both high specific capacitance and outstanding cycling performance.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
RUSSIAN JOURNAL OF ELECTROCHEMISTRY
·
2025
·Vol. 61
·期 5
·163-176
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IF 0.8
Fei Ruan,Lei Chonggui,Wu Xi,Bao Jinxiao,Zhou Fen,Gao Jianquan,Liu Guoqi,Tian Zhen
To gain a more thorough understanding of the conductive mechanism of Sc-doped CaZrO 3 electrolyte, solid electrolyte specimens of CaZr 1 − x Sc x O 3 − δ (with x values of 0.06, 0.12, 0.18, and 0.24, hereinafter referred to as CZS) were meticulously prepared using a high-temperature solid-state method. The phase structure of the electrolyte was thoroughly analyzed using X-ray diffraction (XRD). The electrical conductivity of the CZS electrolyte was rigorously tested within a temperature range of 573 to 1473 K, both in oxygen-rich and hydrogen-rich atmospheres, employing the two-terminal AC impedance spectroscopy method. Additionally, the H/D isotope effect of the electrolyte at various temperatures in both H 2 and D 2 atmospheres was meticulously examined through AC impedance spectroscopy. The electromotive force (EMF) of the electrolyte was precisely measured by a high-impedance ohmmeter at temperatures ranging from 573 to 1273 K. Furthermore, based on crystal defect chemistry theory, estimates were made for the partial conductivities of the conducting species, the active doping concentration of Sc, and the standard Gibbs free energy changes associated with the production of interstitial protons through the dissolution of water and hydrogen within the CZS electrolyte. The results clearly indicated that protons serve as the primary charge carrier in both oxygen-rich and hydrogen-rich atmospheres at temperatures below 1073 K. However, as temperatures rise above 1073 K, the situation changes: in hydrogen-rich atmospheres, oxygen ion vacancies emerge as the dominant charge carrier, whereas in oxygen-rich atmospheres, electron holes take precedence. Notably, CZY stands out as a promising candidate for a proton-conducting electrolyte material, suitable for high-temperature hydrogen sensors.
研究领域:
材料科学
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固体化学
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能源工程
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电化学
✓ 已验证
产品关联
DOI
高影响因子
Small Structures
·
2024
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IF 13.9
Wenxuan Hu,Bin Hu,Ziliang Wu,Min Zuo,Yihu Song,Qiang Zheng,Guorong Shan,Miao Du
Layered double hydroxides (LDHs) are a class of promising cathode materials for supercapacitors. However, the bad cycling performance has always been the Achilles’ heel of LDHs-based supercapacitors. In this contribution, a nonelectrochemical active element Scandium (Sc) is doped into NiCo-LDHs to greatly improve the intrinsic cycling performance of active materials. The trimetallic NiCoSc-LDHs exhibit an ultralong cycle lifespan with 40 000 charge–discharge cycles (exceeding 50 days) and a high specific capacity of 196 mAh g −1 (1695 F g −1 ). Sc doping greatly changes the degradation mode of NiCo-LDHs from rapid decay in thousands of cycles to a two-stage performance evolution, which consists of a superlong activation process of about 10 000 cycles and then extremely slow degradation. Moreover, Sc doping enhances the electrochemical activity of Ni 3+ , so as to not only avoid its Jahn–Teller distortion, but also perform as a structural stabilizer to alleviate the local strain of host layer. The assembled asymmetric supercapacitor delivers an ultralong cycling lifespan with 101% capacity retention even after 50 000 cycles. This work presents a new pathway to significantly improve the electrochemical performance, especially the cycling stability of LDH-based electrodes for high-performance supercapacitors.
研究领域:
材料科学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED MATERIALS
·
2023
·
IF 29.4
Li Ya Liang,Bin Bin Chen,Ya Ting Gao,Jian Lv,Meng Li Liu,Da Wei Li
Achieving aqueous solution enhanced room temperature phosphorescence (RTP) is critical for the applications of RTP materials in solution phase, but which faces a great challenge. Herein, for the first time, a strategy of coordination-induced structural rigidity is proposed to achieve enhanced quantum efficiency of aluminum/scandium-doped phosphorescent microcubes (Al/Sc-PMCs) in aqueous solution. The Al/Sc-PMCs in a dry state exhibit a nearly invisible blue RTP. However, they emit a strong RTP emission in aqueous solution with a RTP intensity increase of up to 22.16-times, which is opposite to common solution-quenched RTP. The RTP enhancement mechanism is attributed to the abundant metal sites (Al 3+ and Sc 3+ ions) on the Al/Sc-PMCs surface that can tightly combine with water molecules through the strong coordination. Subsequently, these coordinated water molecules as the bridging agent can bind with surface groups by hydrogen bonding interaction, thereby rigidifying chemical groups and inhibiting their motions, resulting in the transition from the nonradiative decay to the radiative decay, which greatly enhances the RTP efficiency of the Al/Sc-PMCs. This work not only develops a coordination rigidity strategy to enhance RTP intensity in aqueous solution, but also constructs a phosphorescent probe to achieve reliable and accurate determination of analyte in complex biological matrices.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
PubMed
高影响因子
SOLID STATE IONICS
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2025
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IF 3.3
Sara Adeeba Ismail,Lulu Jiang,Hui Guo,Wenhao Li,Donglin Han
Ba 7 Nb 4 MoO 20 has acceptably high ionic conductivity at 600–800 °C and is attractive for potential application in high temperature solid state electrochemical devices. Up to now, most of the research focuses on isovalent and donor-doping to improve the electrical properties of Ba 7 Nb 4 MoO 20 . In this work, an acceptor-doping strategy was taken by doping Sc and Zr to partially substitute Nb. More vacant oxygen sites thereby form for charge compensation, leading to the increasing proton concentration following the compositional sequence of hydrated Ba 7 Nb 4 MoO 20 < Ba 7 Nb 3.97 Zr 0.03 MoO 19.985 < Ba 7 Nb 3.97 Sc 0.03 MoO 19.97 . Notably, both the H 2 O/D 2 O isotope effect and EMF measurements indicate that the proton conduction – if there is any – is negligibly small, and the Sc and Zr-doped Ba 7 Nb 4 MoO 20 is essentially an oxide ion conductor in the temperature range studied in this work.
研究领域:
材料科学
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固体离子学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Lianyang Zhang,Zhiling Huang,Shengjie Xia
This paper combines defect engineering and metal doping to prepare transition metal Sc-doped molybdenum sulfide-containing sulfur vacancies (Sc@VS–MoS2), which is used for photocatalytic nitrogen reduction to synthesize ammonia (pNRR). The activity of Sc@VS–MoS2 for pNRR is as high as 124.26 μmol g–1 h–1, which is 6.16, 2.23, and 2.69 times for MoS2, VS-MoS2, and Sc@MoS2, respectively. This indicates that the combination of S vacancies and Sc doping can significantly improve the photocatalytic performance of MoS2 materials. Theoretical calculations show that the energy barrier UL of the potential determining step (PDS) is only −0.393 V, much lower than VS–MoS2, making Sc@VS–MoS2 exhibit excellent nitrogen reduction activity for ammonia synthesis. Computational results demonstrate that Sc@VS–MoS2 exhibits outstanding N2 adsorption and activation properties, with 0.533 e charge transfer to N2 that significantly reduces the free energy barrier for the first hydrogenation step. Moreover, its hydrogen adsorption free energy is substantially lower than that of VS-MoS2, effectively suppressing the competing hydrogen evolution reaction and enhancing N2 reduction selectivity. In situ infrared spectroscopy showed the formation of −N2Hy species on the catalyst surface, indicating that the enzyme pathway is the most likely reaction pathway, consistent with the calculated results.
研究领域:
催化
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材料科学
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环境科学
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理论化学
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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）