ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Lifeng Jiang,Shuyue Tan,Rongchun Chen,Jingwei Xian,Hongrui Li,Donghu Zhou,Huijun Kang,Zongning Chen,Enyu Guo,Tongmin Wang
Grain boundary (GB) engineering includes grain size and GB segregation. Grain size has been proven to affect the electrical properties of Mg3(Sb, Bi)2 at low temperatures. However, the formation mechanism of GB segregation and what kind of GB segregation is beneficial to the performance are still unclear. Here, the Ga/Bi cosegregation at GBs and Mg segregation within grains optimize the transport of electrons and phonons simultaneously. Ga/Bi cosegregation promotes the formation of Janus-like structures due to the diverse ordering tendencies of liquid Mg3Sb2 and Mg3Bi2 and the absence of a solid solution of Ga/Bi. The Janus-like structure significantly reduces the room-temperature lattice thermal conductivity by introducing diverse microdefects. Meanwhile, a coherent interface between the nano Mg segregation region and the matrix is formed, which reduces the thermal conductivity without affecting the carrier transport. Furthermore, the band structure calculations show that Ga doping introduces the resonance level, increasing the Seebeck coefficient. Finally, the lattice thermal conductivity reaches ∼0.4 W m–1 K–1, and a high average ZT of 1.21 between 323 and ∼773 K is achieved for Mg3.2Y0.02Ga0.03Sb1.5Bi0.5. This work provides guidance for improving the thermoelectric performance via designing cosegregation.
研究领域:
材料科学
·
热电材料
✓ 已验证
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2024
·
IF 3.8
Li-Qin Yu,Rui-Xue Liang,Juan Chen,Sheng-Ming Xie,Bang-Jin Wang,Jun-Hui Zhang,Li-Ming Yuan
Macrocycles play vital roles in supramolecular chemistry and chromatography. 1,1′-Bi-2-naphthol (BINOL)-based chiral polyimine macrocycles are an emerging class of chiral macrocycles that can be constructed by one-step aldehyde-amine condensation of BINOL derivatives with other building blocks. These macrocycles exhibit good characteristics, such as facile preparation, rigid cyclic structures, multiple chiral centers, and defined molecular cavities, that make them good candidates as new chiral recognition materials for chromatographic enantioseparations. In this study, a BINOL-based [2+2] chiral polyimine macrocycle was synthesized by one-step condensation of enantiopure ( S )-2,2′-dihydroxy-[1,1′-binaphthalene]-3,3′-dicarboxaldehyde with (1R,2R)-1,2-diaminocyclohexane. The product was modified with 5-bromo-1-pentene and then attached to thiolated silica using click chemistry to construct a new chiral stationary phase (CSP). The enantioselectivity of the new CSP was explored by separating various racemates under normal phase (NP) and reversed phase (RP) high performance liquid chromatography (HPLC). Thirteen racemates and eight racemates were enantioseparated under the two separation modes, respectively, including chiral alcohols, phenols, esters, ketones, amines, and organic acids. Among them, nine racemates achieved baseline separation under NP-HPLC and seven racemates achieved baseline separation under RP-HPLC. High resolution separation was observed with benzoin ( Rs = 5.10), epinephrine ( Rs = 4.98), 3-benzyloxy-1,2-propanediol ( Rs = 4.42), and 4,4′-dimethylbenzoin ( Rs = 4.52) in NP-HPLC, and with 4-methylbenzhydrol ( Rs = 4.72), benzoin ethyl ether ( Rs = 3.79), 1-phenyl-1-pentanol ( R s = 3.68), and 1-(3-bromophenyl)ethanol ( Rs = 3.60) in RP-HPLC. Interestingly, the CSP complemented Chiralcel OD-H, Chiralpak AD-H, and CYCLOBOND I 2000 RSP columns for resolution of these test racemates, separating several racemic compounds that could not be well separated by the three commercially available columns. The influences of injected sample amount on separation were also evaluated. It was found that the column exhibited excellent stability and reproducibility after hundreds of injections, and the relative standard deviations ( n = 5) of the retention time and resolution were less than 0.49% and 0.69%, respectively. This study indicates that the BINOL-based chiral macrocycle has great potential for HPLC enantioseparation.
研究领域:
分析化学
·
色谱技术
·
有机化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Today Physics
·
2025
·
IF 9.7
Jisheng Liang,Qi Zhou,Zhengniu Pan,Zhongwei Zhang,Fengting Mao,Shiyuan Zhao,Sijing Zhu,Jun-liang Chen,Jie Gao,Lei Miao
N-type Mg 3 (Sb,Bi) 2 Zintl compounds have emerged as promising candidates for high-temperature energy applications due to their exceptional thermoelectric performance, making them pivotal in the development of sustainable energy technologies. Despite recent advancements, these materials suffer from low carrier mobility caused by polar covalent bonds , which degrade electrical conductivity and overall thermoelectric efficiency. In this study, we introduce beryllium , a bivalent homologous group element, as a cationic dopant to substitute for Mg in Mg 3.2 Sb 1.5 Bi 0.49 Te 0.01 . This substitution weakens the polarity of the chemical bonds, significantly enhancing carrier mobility from ∼62 to ∼138 cm 2 V −1 s −1 . Theoretical analysis using the single parabolic band model confirms that the effective mass decreases with increasing Be doping content. First-principles calculations further reveal that Be doping leads to stronger charge localization due to their higher electronegativity and shifts the Fermi level into the conduction band and narrows the band gap, strengthening the n-type semiconducting properties. This optimization yields an impressive power factor of ∼2022 μW m −1 K −2 at 523 K in Mg 3.12 Be 0.08 Sb 1.5 Bi 0.49 Te 0.01 , owing to the improved carrier mobility . Furthermore, the Be atoms as point defects induces significant lattice distortions and strains, effectively suppressing lattice thermal conductivity to ∼0.38 W m −1 K −1 at 573 K. Consequently, we achieve a remarkable ZT of 1.54 at 673 K and a high average ZT of 1.17 in n-type Mg 3.14 Be 0.06 Sb 1.5 Bi 0.49 Te 0.01 . Our work offers new strategies to enhance the thermoelectric properties of n-type Mg 3 (Sb,Bi) 2 materials, advancing high-temperature sustainable energy technologies.
研究领域:
材料科学
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热电材料
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固态化学
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能源材料
·
半导体物理
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2025
·
IF 12.1
Jie Huang,Kangpeng Jin,Chen Li,Hao Yang,Yiming Zhang,Xiyang Wang,Ming Huang,Zhen-Hua Ge,Liangwei Fu
Maximizing the average figure-of-merit ( ZT avg ) of thermoelectric (TE) materials is crucial for optimizing the module performance. Herein, this work enhances the ZT avg to 1.42 (298–673 K) in a n-type Mg 3 (Sb, Bi) 2 -based material by a stepwise optimization strategy. Specifically, Cr injects electron into Mg 3 Sb 0.8 Bi 1.19 Te 0.01 , which synergistically boosts carrier concentration and forms an electron accumulation layer at the interface. Meanwhile, lattice softening and interfacial scattering suppress lattice thermal conductivity. A peak ZT of 1.72 at 673 K and ZT avg of 1.30 over 298–673 K are achieved for Mg 3 Sb 0.8 Bi 1.19 Te 0.01 –1.5 wt.% Cr. Then, through grain refinement and Se doping instead of Te, a delicate equipoise is reached between the power factor and the electronic thermal conductivity. Eventually, the Mg 3 Sb 0.8 Bi 1.19 Se 0.01 –1.5 wt.% Cr sample obtains an outstanding ZT of ≈1.9 at 573 K and ZT avg of 1.42 over 298–673 K. The integrated two-pair full-Zintl YbZn 2 Sb 2 /Mg 3 (Sb, Bi) 2 module achieves a high conversion efficiency of 10.5% and power density of 0.37 W cm −2 simultaneously under a temperature difference of 370 K. More importantly, this module exhibits excellent thermal stability during a 10-day in situ test. This work provides new ideas for applications of full-Zintl modules to the recovery of waste heat.
研究领域:
材料科学
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热电学
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能量转换
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固体物理
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可持续能源
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2023
·Vol. 11
·期 43
·23319-23329
·
IF 11.9
Bang-Zhou Tian,Yi-Yan Liao,Fang Xu,Xiao-Ling Qiu,Fu-Jie Zhang,Ran Ang
Interfacial modulation has been considered an effective strategy to enhance the thermoelectric (TE) performance by decoupling thermal and electrical parameters. However, inappropriate interfacial heterojunctions can significantly deteriorate electrical transport while enhancing phonon scattering, which causes no substantial improvement in TE performance. Herein, we introduce two-dimensional graphene or MXene into the Mg3.2Sb0.5Bi1.49Te0.01 matrix by ball mixing combined with rapid sintering to modify the composition and structure at the interface. The differences in morphology, size and distribution of interfacial graphene and MXene lead to distinct results which show that incorporated graphene flakes with larger size hinder the carrier transport, while the homogeneously dispersed tiny MXene provides improved carrier channels and boosts the mobility. On the other hand, such uniformly diffused heterogeneous MXene structures create stronger scattering on phonons compared to enriched graphene phases, resulting in a low lattice thermal conductivity of ∼0.66 W m−1 K−1 and enhanced zT of ∼1.0 at 513 K in Mg3.2Sb0.5Bi1.49Te0.01-0.6 wt% MXene with good component stability in air. This work highlights the importance of size, concentration, and distribution in the interfacial modulation strategy, demonstrating an effective method for developing high TE performance Mg3(Sb, Bi)2-based near-room-temperature materials.
研究领域:
材料科学
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凝聚态物理
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纳米材料
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能源材料
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固体化学
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Mengyun Lu,Xinwen Jia,Wenjing Zhang,Wuduo Zhao,Ajuan Yu,Gangfeng Ouyang
The enantioselective performance of porous chiral metal–organic frameworks (CMOFs) is closely related to the pore size and uniformity of easily accessible active sites. The chiral recognition efficiency of microporous CMOFs is hindered by the restricted diffusion of the guest. Hierarchical porous chiral CMOFs with multiple pore size regimes ranging from micropores to macropores have emerged as potential candidates in chiral separation applications. 3DOM Zn-MOF-74 crystalline porous material with ordered macro–micropore structure was prepared with a general bottom-up strategy by carrying out the controllable confined growth of Zn-MOF-74 precursor in a removable three-dimensional ordered macroporous (3DOM) polystyrene (PS) template. Then l-tryptophan ( l -Trp) was introduced into MOFs by the strategy of postsynthetic modifications, and finally, a chiral hierarchical porous functional material 3DOM Zn-MOF-74-l-Trp was successfully fabricated. Based on the two luminescent centers from the achiral ligand H4DOBC and chiral ligand l-Trp, the proportional fluorescence sensor 3DOM Zn-MOF-74-l-Trp was hopeful to be applied in the field of enantioselective fluorescence sensing. The enantioselectivity factor values of microporous M-Zn-MOF-74-l-Trp for 1,1′-bi-2-naphthol (Binol) and mandelic acid (MA) were 1.08 and 1.12, respectively. In comparison, the construction of hierarchical porous structure greatly enhanced the chiral recognition performance, which may be due to the improved mass-transfer efficiency of chiral guest molecules and highly swelled accessibility to the chiral recognition sites in this CMOF composite, making the enantioselectivity factor values correspondingly increased to 1.29 and 2.26, respectively.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Energy Materials
·
2025
·
IF 5.5
Mingxing Guo,Aojie Zhang,Chao Wu,Wenhao Fan,Qiang Zhang,Shaoping Chen
The n-type Mg3(Sb,Bi)2-based thermoelectric materials are promising candidates for medium-temperature power generation due to their low cost, nontoxicity, and high performance. However, their large-scale application in thermoelectric devices is significantly hindered by poor long-term stability, resulting from electrode interface degradation. Effective contact interfaces in thermoelectric devices require high bonding strength, low interfacial resistivity, and exceptional stability. Therefore, the development of efficient and reliable thermoelectric interface materials is crucial for the practical application of these devices. Conventional approaches to forming interfacial barrier layers mainly rely on thermodynamic equilibrium, which often overlook the critical roles of interfacial reactions and diffusion kinetics. In this study, molecular dynamics simulations were employed to uncover the underlying mechanisms responsible for the high stability of the Mg2Ni barrier layer and its interface with thermoelectric materials. The Mg2Ni/Mg3.21Sb1.5Bi0.5Y0.04 thermoelectric device exhibited excellent performance, with a low contact resistance of 11 μΩ·cm2, a high output power density of 1.2 W·cm–2, and an energy conversion efficiency of 5% at a temperature difference of ΔT = 373 K. This strategy is applicable to other thermoelectric materials, offering valuable insights for designing barrier layers in diverse thermoelectric systems.
研究领域:
材料科学
·
热电学
·
界面工程
·
扩散动力学
·
能量转换
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）