Journal of Materials Chemistry A
·
2024
·
IF 10.7
Jing Zhang,Jin Chen,Jian Wei,Yanyi Liu,Yuzhao Ma,Xiaofeng Yang,Yanjun Li
The unique structure of medium entropy materials has garnered significant attention in the field of batteries. Medium-entropy spinel ferrite, as a new cathode material for lithium–sulfur batteries, presents boundless possibilities to tailor charge–discharge performance. Herein, abundant oxygen vacancies were implanted into medium-entropy spinel ferrites and utilized as cathode materials for lithium–sulfur batteries to address the challenges associated with the sluggish shuttle and conversion kinetics of lithium polysulfides (LiPSs) during charge–discharge processes in Li–S batteries. The synergistic effects among multiple species highlight the advantages of medium entropy features. The presence of oxygen vacancies mitigates the energy barrier associated with the decomposition reaction, thereby facilitating charge transfer kinetics and promoting LiPSs conversion. Oxygen vacancies can be readily implanted into the medium-entropy spinel ferrite, thereby enabling the distinctive medium-entropy-driven influence of oxygen vacancies on the favorable rate capability and prolonged cycling performance of lithium–sulfur batteries. This study presents a promising approach for utilizing design defects in medium-entropy ferrites within the realm of battery applications.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Dong Wang,Fengqin Tang,Hui Bai,Pengju Wu,Yaju Zhang,Lingyun Fang,Beibei Sun,Chunhui Shi,Libing Hu
The fabrication of advanced electrocatalysts for urea-assisted electrolytic water splitting is of great significance for yielding green hydrogen. In this study, Ce doping a quaternary sea urchin like medium-entropy NiCoFe layered double hydroxide (Ce 1.2 -NiCoFe-LDH) nanoshe et s were obtained by employing a doping engineering strategy. Characterization experimental results confirmed that Ce dopants could modify the oxygen vacancy structure of NiCoFe-LDH, accelerating charge and mass transfer. thereby enhancing the urea decomposition. The electrochemical results indicated that Ce 1.2 -NiCoFe-LDH demonstrated high-efficiency catalysis for UOR, characterized by high intrinsic activity, rapid kinetics, and robust durability. The overpotential of Ce 1.2 -NiCoFe-LDH was only 48 mV at the current density of 10 mA cm −2 , much lower than the commercial IrO 2 (126 mV at 10 mA cm −2 ). The tafel slope of Ce 1.2 -NiCoFe-LDH (62 mV dec −1 ) was also better than those of IrO 2 (88 mV dec −1 ) and NiCoFe-LDH (99 mV dec −1 ). Compared with the commercial IrO 2 , the Ce 1.2 -NiCoFe-LDH exhibited a change of only 3.2 % after a 12-hour chronoamperometric test, indicating an improvement in stability. Impedance comparison between the two hydrotalcites revealed that Ce 1.2 -NiCoFe-LDH possessed lower impedance, potentially enhancing catalytic efficiency. Therefore, this work illustrates that the modulation of oxygen vacancies in electrocatalysts, induced by the heteroatom doping effect, can enhance the electrocatalytic oxidation performance of small molecules for hydrogen production.
研究领域:
材料科学
·
电化学
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
Batteries-Basel
·
2023
·Vol. 9
·期 2
·91
·
IF 4
Wentao Wu,Shuai Zuo,Xu Zhang,Xuyong Feng
Solid state reaction is widely used in the synthesis of electrode materials, due to its low cost and good scalability. However, the traditional solid-state reaction is not suitable for the synthesis of materials with multiple elements, such as high entropy or medium entropy materials, due to the poor homogeneity of raw material mixing. Here, we prepared multi-element doped LiNi0.5Mn1.5O4(medium entropy) cathode material by two step solid state reaction. X-ray diffraction and Raman image show that the homogeneity of multi-element doped LiNi0.5Mn1.5O4cathode has been greatly improved with this two-step method. As a result, the electrochemical performance is greatly improved, comparing to traditional solid-state reaction. First, the specific capacity at 0.1 C is increased from 126 mAh/g to 137 mAh/g. With a high current density of 10 C, the specific capacity is even increased from 64 mAh/g to 89 mAh/g with this two-step method. Second, the cycle stability is enhanced, with capacity retention of 86% after cycling at 1 C for 500 times (vs. 71% for the one-step method).
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Xue-Zhi Song,Xiao-Bing Wang,Tao Zhang,Ji-Hong Dong,Yu-Lan Meng,De-Kun Liu,Yu-Xin Luan,Changguang Yao,Zhenquan Tan,Xiao-Feng Wang
High-/medium-entropy materials have been explored as promising electrocatalysts for water splitting due to their unique physical and chemical properties. Unfortunately, state-of-the-art materials face the dilemma of explaining the enhancement mechanism, which is now limited to theoretical models or an unclear cocktail effect. Herein, a medium-entropy NiCoFeMnP with an advanced hierarchical particle-nanosheet-tumbleweed nanostructure has been synthesized via simple precursor preparation and subsequent phosphorization. Evaluated as the electrocatalyst for oxygen evolution reaction (OER), the medium-entropy NiCoFeMnP displays a lower overpotential of 272 mV at a current density of 10 mA cm–2, and more favorable kinetics than the binary NiFeP, ternary NiCoFeP, quaternary NiCoFeCuP and NiCoFeCrP counterparts, and other reported high-/medium-entropy electrocatalysts. Careful experimental analyses reveal that the incorporation of Mn can significantly regulate the electronic structure of Ni, Co, and Fe sites. More importantly, the Mn introduction and entropy stabilization effect in the reconstructed metal (oxy)hydroxide simultaneously promote the lattice oxygen mechanism, improving the activity. This work sheds new light on the design of high-/medium-entropy materials from an in-depth understanding of the underlying mechanism for improving energy conversion efficiency.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DALTON TRANSACTIONS
·
2025
·
IF 3.3
Yuxin Luan,De-Kun Liu,Yuxiang Chen,Xuezhi Song,Liang Jing,Xiao-Bing Wang,Wenqiang Sun,Yulan Meng,Chenyu Shen,Ruichen Zhou,Jinxuan Liu,Xiaofeng Wang,Zhenquan Tan
Developing highly efficient and durable electrocatalysts for oxygen evolution reaction (OER) holds great promise in revolutionizing the sustainable energy-conversion technologies, which are greatly relying on the surface electronic structures. However, constructing catalytically active medium-entropy materials encounters great challenge due to the complexed composition and the unsolved electronic structure-performance relationship. In this study, the medium-entropy metal selenide (CoFeNiSe) with cumulus-like architectures is fabricated through the selenylation of trimetallic hydroxide precursors. The medium-entropy CoFeNiSe manifests an outstanding electrocatalytic OER activity and kinetics, that is a low overpotential of 268 mV at 10 mA cm-2 and a Tafel slope of 53.33 mV dec-1, in 1 M KOH, outperforming the entropy-poor binary CoFeSe and CoNiSe, as well as unary CoSe counterparts. It has been found experimentally and theoretically that the effective modulations of the valency and the d-band center at an optimal level regulate the adsorption/desorption ability of reaction intermediates via multimetallic electron interactions. This work provides the valuable insight into the electronic structure regulation in entropy-rich materials, shedding light on the development of current green energy conversion technologies.
研究领域:
材料科学
·
电化学
·
催化
·
能量转换
·
纳米技术
·
计算化学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）